高須　夫悟TAKASU Fugoタカス　フウゴ

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プロフィール情報

• 姓

  高須, タカス

• 名

  夫悟, フウゴ

学位

• 博士(理学), 京都大学

研究キーワード

• 生物集団の構造並びに進化に関する数理的研究

研究分野

• ライフサイエンス, 生物物理学

経歴

• 2007年01月, 奈良女子大学理学部教授
• 2000年11月, 2006年12月, 奈良女子大学理学部助教授
• 1997年01月, 2000年11月, 奈良女子大学理学部講師
• 1994年09月, 1996年12月, 奈良女子大学理学部助手
• 1994年04月, 1994年08月, 日本学術振興会特別研究員 DC

学歴

• 1990年04月, 1994年08月, 京都大学, 理学研究科, 生物物理学
• 1990年03月, 京都大学, 理学部, 生物物理学

担当経験のある科目（授業）

• 実践環境科学英語演習II, 奈良女子大学
• 数理生物環境動態学特論演習, 奈良女子大学
• 実践環境科学英語演習I, 奈良女子大学
• 社会に出るまでに市っておきた科学 - 物語としての科学, 奈良女子大学
• 数理生物環境動態学特論, 奈良女子大学
• 数理生命科学セミナーⅠ, 奈良女子大学
• 数理生命科学特論Ⅰ, 奈良女子大学
• 数理生態学概論, 奈良女子大学
• パサージュ（２４Ａ）, 奈良女子大学
• 社会に出るまでに知っておきたい科学 - 物語としての科学 -, 奈良女子大学
• サイエンス・オープンラボ II E, 奈良女子大学
• サイエンス・オープンラボ I E, 奈良女子大学
• アカデミックガイダンス（サクラ・サイエンス）「生き物たちの数理」, 奈良女子大学
• 環境科学計算機実験, 奈良女子大学
• パサージュ 24A, 奈良女子大学
• 個体群動態の数理, 奈良女子大学
• 環境科学概論, 奈良女子大学
• アカデミック・ガイダンス 2015, 奈良女子大学
• 化学生命環境学入門, 奈良女子大学
• サイエンス・オープンラボⅡ（Ｅ）, 奈良女子大学
• サイエンス・オープンラボⅠ（Ｅ）, 奈良女子大学
• 計算機実験１, 奈良女子大学
• 情報数学２, 奈良女子大学
• プロジェクト演習（Ｅ）, 奈良女子大学
• 環境科学基礎プログラミング演習, 奈良女子大学
• 環境科学基礎プログラミング, 奈良女子大学
• 計算機実験２, 奈良女子大学
• プログラミング演習１, 奈良女子大学
• プログラミング言語１, 奈良女子大学
• サイエンスオープンラボE, 奈良女子大学
• 現代社会と職業, 奈良女子大学
• サイエンス・オープンラボ（情報科学科）, 奈良女子大学
• サイエンス・オープンラボI, II, 奈良女子大学
• 情報システムモデル論演習, 奈良女子大学
• 情報システムモデル論, 奈良女子大学
• 生態情報学特別講義, 奈良女子大学
• 情報科学特別講義2, 奈良女子大学
• 情報数学2, 奈良女子大学
• キャリアデザインゼミナール 少子高齢化, 奈良女子大学
• 情報科学特別講義I, 奈良女子大学
• 計算機実験1, 奈良女子大学
• 計算機実験2, 奈良女子大学
• 情報科学特別講義1, 奈良女子大学
• キャリアデザイン・ゼミナール 少子高齢化を理解する, 奈良女子大学
• サイエンス・オープンラボ 情報科学科, 奈良女子大学
• 生態情報学特論演習, 奈良女子大学
• 生態情報学特論, 奈良女子大学
• キャリアデザイン・ゼミナール 少子高齢化を分析する力をつける, 奈良女子大学
• 情報科学特別講義 I, 奈良女子大学
• 計算機実験 2, 奈良女子大学
• 大域情報学, 奈良女子大学

所属学協会

• 日本生態学会
• 日本数理生物学会
• 日本鳥学会

Ⅱ．研究活動実績

論文

• 査読あり, 英語, Journal of Theoretical Biology, Elsevier, Spatial metapopulation dynamics with local and global colonization, 2023年年9月, 10.1016/j.jtbi.2023.111579
• 査読あり, 英語, Frontiers in Plant Science, Simulating Pine Wilt Disease Dispersal With an Individual-Based Model Incorporating Individual Movement Patterns of Vector Beetles, 2022年05月22日, 13, 10.3389/fpls.2022.886867
• 査読あり, その他, Applied Mathematical Modelling, Asymptotic behaviors of stochastic epidemic models with jump-diffusion, Nguyen Thanh Dieu; Takasu Fugo; Nguyen Huu Du, 2020年10月, 86, 259, 270, 研究論文（学術雑誌）, 10.1016/j.apm.2020.05.003

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• 査読あり, その他, Journal of Sichuan University (Engineering Science Edition), 日本梅花鹿与大丰麋鹿发情期反刍行为的差异, Zhang Yigui; Ullah Sana; TAKASU Fugo; Li Zhongqiu, 2020年01月, 39, 50, 55
• 査読あり, 日本語, 日本森林学会誌101巻1号30-34, マツ枯れ進展における潜在感染木の役割に関する数理的研究, 高須夫悟, 2019年01月, 101, 1, 30-34, 10.4005/jjfs.101.30

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• 査読あり, 英語, Journal of Theoretical Biology, Equilibrium properties of the spatial SIS model as a point pattern dynamics - How is infection distributed over space?, 高須夫悟; Hamada Miki; Fugo Takasu, 2019年, 468, 12-26, 10.1016/j.jtbi.2019.02.005

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• 査読あり, 英語, ECOLOGY AND EVOLUTION, How can distinct egg polymorphism be maintained in the rufescent prinia (Prinia rufescens)-plaintive cuckoo (Cacomantis merulinus) interaction-a modeling approach, Wei Liang; Canchao Yang; Fugo Takasu, In avian brood parasitism, both the host and the parasite are expected to develop various conflicting adaptations; hosts develop a defense against parasitism, such as an ability to recognize and reject parasitic eggs that look unlike their own, while parasites evolve egg mimicry to counter this host defense. Hosts may further evolve to generate various egg phenotypes that are not mimicked by parasites. Difference in egg phenotype critically affects the successful reproduction of hosts and parasites. Recent studies have shown that clear polymorphism in egg phenotype is observed in several host-parasite interactions, which suggests that egg polymorphism may be a more universal phenomenon than previously thought. We examined the mechanism for maintaining egg polymorphism in the rufescent prinia (Prinia rufescens) that is parasitized by the plaintive cuckoo (Cacomantis merulinus) from a theoretical viewpoint based on a mathematical model. The prinia has four distinct egg phenotypes: immaculate white, immaculate blue, white with spots, and blue with spots. Only two egg phenotypes, white with spots and blue with spots, are found in the cuckoo population. We show that the observed prinia and cuckoo phenotypes cannot be at an equilibrium and that egg polymorphism can be maintained either at stationary equilibrium or with dynamic, frequency oscillations, depending on the mutation rates of the background color and spottiness. Long-term monitoring of the prinia-cuckoo interaction over a wide geographic range is needed to test the results of the model analyses., 2017年08月, 7, 15, 5613, 5620, 研究論文（学術雑誌）, 10.1002/ece3.3090

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• 査読あり, 英語, ECOLOGICAL MODELLING, Spatially explicit model applied to pine wilt disease dispersal based on host plant infestation, Tuyen Van Nguyen; Young-Seuk Park; Chang-Sik Jeoung; Won-Il Choi; Yong-Kuk Kim; Il-Hyo Jung; Nanako Shigesada; Kohkichi Kawasaki; Fugo Takasu; Tae-Soo Chon, Pine wilt disease is a serious pest for pine trees in many countries, especially in Asia (e.g., South Korea, Japan, China and Taiwan). In this study, we characterised dispersal patterns (e.g., direction and area) of pine wilt disease in the southern part of Korea in four-year period based on the cross-correlation function. The most likely distance of the highest infestation probability after one year is around 1.2 km from the disease source according to the distribution of pairwise distance. Subsequently, a spatially explicit model was developed in two dimensions by incorporating biological and environmental events, including influence of infested neighbourhoods, short- and long-distance dispersal, asymptomatic carriers and typhoon. The model results were in good agreement with field data when evaluated using the receiver operating characteristics and pair-correlation functions. Asymptomatic carrier played an important role in the spread of PWD. The infestation probabilities based on the spatially explicit model provided the map of spatial conformations that would be effective in addressing disease occurrence in both local and global aspects. (C) 2016 Elsevier B.V. All rights reserved., 2017年06月, 353, 54, 62, 研究論文（学術雑誌）, 10.1016/j.ecolmodel.2016.10.022

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• 査読あり, 英語, BIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY, Disappearance of eggs from nonparasitized nests of brood parasite hosts: the evolutionary equilibrium hypothesis revisited, Bard G. Stokke; Eivin Roskaft; Arne Moksnes; Anders Pape Moller; Anton Antonov; Frode Fossoy; Wei Liang; German Lopez-Iborra; Csaba Moskat; Jacqui A. Shykoff; Manuel Soler; Johan R. Vikan; Canchao Yang; Fugo Takasu, The evolutionary equilibrium hypothesis was proposed to explain variation in egg rejection rates among individual hosts (intra- and interspecific) of avian brood parasites. Hosts may sometimes mistakenly reject own eggs when they are not parasitized (i.e. make recognition errors). Such errors would incur fitness costs and could counter the evolution of host defences driven by costs of parasitism (i.e. creating equilibrium between acceptors and rejecters within particular host populations). In the present study, we report the disappearance of host eggs from nonparasitized nests in populations of seven actual and potential hosts of the common cuckoo Cuculus canorus. Based on these data, we calculate the magnitude of the balancing parasitism rate provided that all eggs lost are a result of recognition errors. Importantly, because eggs are known to disappear from nests for reasons other than erroneous host rejection, our data represent the maximum estimates of such costs. Nonetheless, the disappearance of eggs was a rare event and therefore incurred low costs compared to the high costs of parasitism. Hence, costs as aresult of recognition errors are probably of minor importance with respect to opposing selective pressure for theevolution of egg rejection in these hosts. We cannot exclude the possibility that low or intermediate egg rejection rates in some host populations may be caused by spatiotemporal variation in the occurrence of parasitism and gene flow, creating a variable influence of opposing costs as a result of recognition errors and the costs of parasitism., 2016年06月, 118, 2, 215, 225, 研究論文（学術雑誌）, 10.1111/bij.12733

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• 査読あり, 英語, JOURNAL OF ETHOLOGY, Modeling the cuckoo's brood parasitic behavior in the presence of egg polymorphism, Wei Liang; Canchao Yang; Fugo Takasu, The common cuckoo Cuculus canorus is a brood parasite that utilizes many host species. These have evolved defense against parasitism to reject cuckoo eggs that look unlike their own and some cuckoos have evolved egg mimicry to counter this defense. Egg phenotype indeed plays a key role for both the cuckoo and its hosts to successfully reproduce. It has been argued that cuckoos should parasitize host nests where egg phenotype matches because this makes parasitism more successful. Details of the cuckoo's parasitic behavior, however, largely remains unknown if they really parasitize hosts depending on "egg matching". In this paper, we model a time sequence of parasitic events in which a cuckoo finds host nests and decides to parasitize them or not in the presence of egg polymorphism. We evaluate which strategy is optimal: (1) opportunistic parasitism where cuckoos parasitize hosts irrespective of the phenotype, or (2) non-opportunistic parasitism where cuckoos parasitize hosts where egg phenotype matches. The analysis showed that either of the two strategies can be optimal. Factors not considered in the model, e.g., ecological and evolutionary changes both in the cuckoo and the host side, are discussed to explain apparent contrasts observed in some cuckoo-host interactions., 2016年05月, 34, 2, 127, 132, 研究論文（学術雑誌）, 10.1007/s10164-015-0455-3

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• 査読あり, 英語, NATURE COMMUNICATIONS, Ancient origin and maternal inheritance of blue cuckoo eggs, Frode Fossoy; Michael D. Sorenson; Wei Liang; Torbjorn Ekrem; Arne Moksnes; Anders P. Moller; Jarkko Rutila; Eivin Roskaft; Fugo Takasu; Canchao Yang; Bard G. Stokke, Maternal inheritance via the female-specific W chromosome was long ago proposed as a potential solution to the evolutionary enigma of co-existing host-specific races (or 'gentes') in avian brood parasites. Here we report the first unambiguous evidence for maternal inheritance of egg colouration in the brood-parasitic common cuckoo Cuculus canorus. Females laying blue eggs belong to an ancient (similar to 2.6 Myr) maternal lineage, as evidenced by both mitochondrial and W-linked DNA, but are indistinguishable at nuclear DNA from other common cuckoos. Hence, cuckoo host races with blue eggs are distinguished only by maternally inherited components of the genome, which maintain host-specific adaptation despite interbreeding among males and females reared by different hosts. A mitochondrial phylogeny suggests that blue eggs originated in Asia and then expanded westwards as female cuckoos laying blue eggs interbred with the existing European population, introducing an adaptive trait that expanded the range of potential hosts., 2016年01月, 7, 10272, 研究論文（学術雑誌）, 10.1038/ncomms10272

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• 査読あり, 英語, JOURNAL OF THEORETICAL BIOLOGY, Beyond pairs: Definition and interpretation of third-order structure in spatial point patterns, Chiho Kaito; Ulf Dieckmann; Akira Sasaki; Fugo Takasu, Spatial distributions of biological species are an important source of information for understanding local interactions at the scale of individuals. Technological advances have made it easier to measure these distributions as spatial point patterns, specifying the locations of individuals. Extensive attention has been devoted to analyzing the second-order structure of such point patterns by focusing on pairs of individuals, and it is well known that the local crowdedness of individuals can thus be quantified. Statistical measures such as a point pattern's pair correlation function or Ripley's K function show whether a given point pattern is clustered (excess of short-distance pairs) or overdispersed (shortage of short-distance pairs). These notions are naturally defined in comparison with control patterns exhibiting complete spatial randomness, i.e., an absence of any spatial structure. However, there is no rational reason why the analysis of point patterns should stop at the second order. In this paper, we focus on triplets of individuals in an attempt to quantify and interpret the third-order structure of a point pattern. We demonstrate that point patterns with "bandedness", in which individuals are primarily distributed within bands, can be detected by an excess of thinner triplets at a characteristic spatial scale linked to the band's width. In this context, we show how the generation of control patterns as a reference for gauging a test pattern's triplet frequencies is critical for defining and interpreting the third-order structure of point patterns. Since perfect information on a point pattern's second-order structure typically suffices for its unique reconstruction (up to translation, rotation, and reflection), we conjecture that it is essential to minimally coarse-grain such second-order information before using it to generate control patterns for identifying a point pattern's third-order structure. We recommend the further exploration of this conjecture for future studies. (C) 2015 Elsevier Ltd. All rights reserved., 2015年05月, 372, 22, 38, 研究論文（学術雑誌）, 10.1016/j.jtbi.2015.02.004

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• 査読あり, 英語, AVIAN RESEARCH, Why cuckoos should parasitize parrotbills by laying eggs randomly rather than laying eggs matching the egg appearance of parrotbill hosts?, Canchao Yang; Fugo Takasu; Wei Liang; Anders P. Moller, The coevolutionary interaction between cuckoos and their hosts has been studied for a long time, but to date some puzzles still remain unsolved. Whether cuckoos parasitize their hosts by laying eggs randomly or matching the egg morphs of their hosts is one of the mysteries of the cuckoo problem. Scientists tend to believe that cuckoos lay eggs matching the appearance of host eggs due to selection caused by the ability of the hosts to recognize their own eggs. In this paper, we first review previous empirical studies to test this mystery and found no studies have provided direct evidence of cuckoos choosing to parasitize host nests where egg color and pattern match. We then present examples of unmatched cuckoo eggs in host nests and key life history traits of cuckoos, e.g. secretive behavior and rapid egg-laying and link them to cuckoo egg laying behavior. Finally we develop a conceptual model to demonstrate the egg laying behaviour of cuckoos and propose an empirical test that can provide direct evidence of the egg-laying properties of female cuckoos. We speculate that the degree of egg matching between cuckoo eggs and those of the host as detected by humans is caused by the ability of the hosts to recognize their own eggs, rather than the selection of matching host eggs by cuckoos. The case of Common Cuckoos (Cuculus canorus) and their parrotbill hosts (Paradoxornis alphonsianus), where it has been shown that both have evolved polymorphic eggs (mainly blue and white), was used to develop a conceptual model to demonstrate why cuckoos should utilize parrotbill hosts by laying eggs randomly rather than laying eggs matching the appearance of host eggs. In conclusion, we found no evidence for the hypothesis that cuckoos lay eggs based on own egg color matching that of the parrotbill-cuckoo system. We argue theoretically that laying eggs matching those of the hosts in this system violates a key trait of the life history of cuckoos and therefore should be maladaptive., 2015年04月, 6, 5, 10.1186/s40657-015-0014-1

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• 査読あり, 英語, WILDLIFE BIOLOGY, Population viability analysis of the Japanese rock ptarmigan Lagopus muta japonica in Japan, Ayaka Suzuki; Atsushi Kobayashi; Hiroshi Nakamura; Fugo Takasu, The Japanese rock ptarmigan Lagopus muta japonica breeds only in limited alpine areas at high elevations (> 2,500 m a.s.1.) in Japan. The estimated population size is about 2,000 birds and their breeding distribution is subdivided into several local areas, in each of which they may be at risk of local extinction. We estimated age-specific demographic parameters of the core population breeding on Mt. Norikura in Gifu and Nagano prefecture in Japan. We also estimated population viability using deterministic and stochastic population models. Age-specific fertility (the number of female offspring that survived to the next breeding season per female) was 0.417 +/- 0.086, 0.490 +/- 0.080, 0.513 +/- 0.153, 0.435 +/- 0.078, 0.562 +/- 0.139, 0.580 +/- 0.122 (mean SE) for ages 1-6 +, respectively. The annual survival rate was 0.739 +/- 0.047, 0.624 +/- 0.064, 0.513 +/- .087, 0.732 +/- 0.151, 0.447 +/- 0.220, 0.486 +/- 0.089. The population growth rate, evaluated by use of a deterministic projection-matrix model, predicted a stable population, lambda= 1.105 +/- 0.063, 95% CI = 0.985-1.231 and lambda= 1.114 +/- 0.062, 0.996-1.239, using two different assumptions for the final age of reproduction by ptarmigan. We evaluated the risk of extinction as the proportion of Xs that was <= 1, and this was <= 4.4%. To complement the deterministic model, we developed an individual-based stochastic population model in which each of the individuals produced a variable number of offspring and survived one year with certain probabilities that were drawn from estimated distributions of age-specific clutch size and survival rates. Averaged population growth rate under the stochastic model was lambda= 1.1, and the risk of extinction defined as the proportion of trials in which population size <= 1 within 30 years was <= 8.9%, even when the starting population was small (15 birds). These results suggest that the local population at Mt. Norikura is stable in size and suffers a relatively low risk of extinction. We suggest that this population can serve as a potential source for surrounding small local populations that may be sink populations., 2013年12月, 19, 4, 339, 346, 研究論文（学術雑誌）
• 査読あり, 英語, ANIMAL COGNITION, Egg arrangement in avian clutches covaries with the rejection of foreign eggs, Lenka Polacikova; Fugo Takasu; Bard G. Stokke; Arne Moksnes; Eivin Roskaft; Phillip Cassey; Mark E. Hauber; Tomas Grim, In birds, the colour, maculation, shape, and size of their eggs play critical roles in discrimination of foreign eggs in the clutch. So far, however, no study has examined the role of egg arrangement within a clutch on host rejection responses. We predicted that individual females which maintain consistent egg arrangements within their clutch would be better able to detect and reject foreign eggs than females without a consistent egg arrangement (i.e. whose eggs change positions more often across incubation). We tested this "egg arrangement hypothesis" in blackbirds (Turdus merula) and song thrush (T. philomelos). Both species are suitable candidates for research on egg rejection, because they show high inter-individual variation and individual repeatability in egg rejection responses. As predicted, using our custom-defined metrics of egg arrangement, rejecter females' clutches showed significantly more consistent patterns in egg arrangement than acceptor females' clutches. Only parameters related to blunt pole showed consistent differences between rejecters and acceptors. This finding makes biological sense because it is already known that song thrush use blunt pole cues to reject foreign eggs. We propose that a disturbance of the original egg arrangement pattern by the laying parasite may alert host females that maintain a consistent egg arrangement to the risk of having been parasitized. Once alerted, these hosts may shift their discrimination thresholds to be more restrictive so as to reject a foreign egg with higher probability. Future studies will benefit from experimentally testing whether these two and other parasitized rejecter host species may rely on the use of consistent egg arrangements as a component of their anti-parasitic defence mechanisms., 2013年09月, 16, 5, 819, 828, 研究論文（学術雑誌）, 10.1007/s10071-013-0615-1

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• 査読あり, 英語, PLOS ONE, Dynamic Regulation of Myosin Light Chain Phosphorylation by Rho-kinase, Takako Kaneko-Kawano; Fugo Takasu; Honda Naoki; Yuichi Sakumura; Shin Ishii; Takahiro Ueba; Akinori Eiyama; Aiko Okada; Yoji Kawano; Kenji Suzuki, Myosin light chain (MLC) phosphorylation plays important roles in various cellular functions such as cellular morphogenesis, motility, and smooth muscle contraction. MLC phosphorylation is determined by the balance between activities of Rho-associated kinase (Rho-kinase) and myosin phosphatase. An impaired balance between Rho-kinase and myosin phosphatase activities induces the abnormal sustained phosphorylation of MLC, which contributes to the pathogenesis of certain vascular diseases, such as vasospasm and hypertension. However, the dynamic principle of the system underlying the regulation of MLC phosphorylation remains to be clarified. Here, to elucidate this dynamic principle whereby Rho-kinase regulates MLC phosphorylation, we developed a mathematical model based on the behavior of thrombin-dependent MLC phosphorylation, which is regulated by the Rho-kinase signaling network. Through analyzing our mathematical model, we predict that MLC phosphorylation and myosin phosphatase activity exhibit bistability, and that a novel signaling pathway leading to the auto-activation of myosin phosphatase is required for the regulatory system of MLC phosphorylation. In addition, on the basis of experimental data, we propose that the auto-activation pathway of myosin phosphatase occurs in vivo. These results indicate that bistability of myosin phosphatase activity is responsible for the bistability of MLC phosphorylation, and the sustained phosphorylation of MLC is attributed to this feature of bistability., 2012年06月, 7, 6, e39269. doi:10.1371/journal.po, 研究論文（学術雑誌）, 10.1371/journal.pone.0039269

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• 査読あり, 英語, JOURNAL OF EVOLUTIONARY BIOLOGY, Modelling the maintenance of egg polymorphism in avian brood parasites and their hosts, W. Liang; C. Yang; B. G. Stokke; A. Antonov; F. Fossoy; J. R. Vikan; A. Moksnes; E. Roskaft; J. A. Shykoff; A. P. Moller; F. Takasu, In avian brood parasitism, egg phenotype plays a key role for both host and parasite reproduction. Several parrotbill species of the genus Paradoxornis are parasitized by the common cuckoo Cuculus canorus, and clear polymorphism in egg phenotype is observed. In this article, we develop a population genetics model in order to identify the key parameters that control the maintenance of egg polymorphism. The model analyses show that egg polymorphism can be maintained either statically as an equilibrium or dynamically with frequency oscillations depending on the sensitivity of the host against unlike eggs and how the parasite targets host nests with specific egg phenotypes. On the basis of the model, we discuss egg polymorphism observed in parrotbills and other host species parasitized by the cuckoo. We suggest the possibility that frequencies of egg phenotypes oscillate and we appeal for monitoring of cuckoohost interactions over a large spatiotemporal scale., 2012年05月, 25, 5, 916, 929, 研究論文（学術雑誌）, 10.1111/j.1420-9101.2012.02484.x

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• 査読あり, 英語, BEHAVIORAL ECOLOGY, Sex roles in egg recognition and egg polymorphism in avian brood parasitism, Wei Liang; Canchao Yang; Anton Antonov; Frode Fossoy; Bard G. Stokke; Arne Moksnes; Eivin Roskaft; Jacqui A. Shykoff; Anders P. Moller; Fugo Takasu, Avian brood parasites impose strong selection on their hosts leading to the evolution of antiparasite defenses like egg recognition and rejection. Discordance and template-based cognitive mechanisms may form the base for egg recognition by hosts. For discordance, hosts recognize eggs that constitute the minority in a clutch as alien, whereas in template-based recognition, hosts recognize eggs as alien when they do not match a template that can be innate or learnt. Template-based recognition by learning can be compromised in host species with polymorphic egg color like Paradoxornis parrotbills, hosts of the common cuckoo Cuculus canorus, because a male that learns an egg color in his first breeding attempt can subsequently mate with females having different colors and therefore reject his own eggs. We present a simple conceptual model to understand how an asymmetry in sex roles of care for eggs and egg polymorphism influence the evolution of egg recognition by hosts. We derive host reproductive success in the presence of variation in egg phenotype for both host and parasite. Our model shows that male recognition by learning is disadvantageous unless the host has monomorphic eggs. We suggest that interclutch variation in egg phenotype is the key to understanding the evolution of egg recognition and the sex involved., 2012年03月, 23, 2, 397, 402, 研究論文（学術雑誌）, 10.1093/beheco/arr203

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• 査読あり, 英語, Zoology, Dr. Mar?a-Dolores Garc?a (Ed.), ISBN: 978-953-51-0360-8, InTech, Development of an individual-based simulation model for the spread of citrus greening disease by the vector insect Diaphorina citri, 高須夫悟, 2012年, 87-102
• 査読あり, 英語, Chinese Birds, Cuckoo parasitism on two closely-related Acrocephalus warblers in distant areas: a case of parallel coevolution?, 高須夫悟, 2012年, 3, 4, 320-329, 10.5122/cbirds.2012.0038

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• 査読あり, 日本語, 野生復帰, 日本におけるコウノトリの再導入個体群の存続可能性分析, 高須夫悟; 大迫義人, 2012年, 2, 1-6
• 査読あり, 英語, JOURNAL OF ZOOLOGY, The analysis of common cuckoo’s egg shape in relation to its hosts’ in two geographically distant areas, 高須夫悟, Evolutionary adaptations are required by common cuckoos Cuculus canorus to match host eggs. Hosts may discriminate against alien eggs; hence, accurate matching of the parasite egg to the hosts' is essential. Egg shape is the least-studied component of egg mimicry, and it may also have other functions: an optimal egg shape is necessary for effective incubation. For this reason, cuckoo eggs may show a wide range of variations in shape to a set of host species. Here, we compare cuckoo and host eggs by using egg shape parameters in two distant areas: from the nests of great reed warblers Acrocephalus arundinaceus, robins Erithacus rubecula and marsh warblers Acrocephalus palustris in Hungary, and oriental reed warblers Acrocephalus orientalis, bull-headed shrikes Lanius bucephalus and black-faced buntings Emberiza spodocephala from Japan. Our results suggest the lack of evolutionary adaptation of different cuckoo gentes to their corresponding hosts in terms of egg shape. However, our analyses revealed that cuckoo eggs showed a geographical difference in egg shape., 2011年06月, 284, 2, 77, 83, 研究論文（学術雑誌）, 10.1111/j.1469-7998.2011.00795.x

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• 査読あり, 英語, JOURNAL OF EVOLUTIONARY BIOLOGY, Isolation by time and habitat and coexistence of distinct host races of the common cuckoo, A. P. Moller; A. Antonov; B. G. Stokke; F. Fossoy; A. Moksnes; E. Roskaft; F. Takasu, Isolation by time occurs when different populations of a single species reproduce at different times and thereby reduce the probability of interbreeding, potentially causing divergent adaptation to timing of reproduction, eventually resulting in ecological species separated by timing of reproduction. We analysed extensive data on timing of reproduction by different host races of the common cuckoo Cuculus canorus that is an obligate brood parasite laying eggs in the nests of many different species of passerine birds. Because different hosts breed at different times, specific host races of cuckoos have adapted to specific hosts by laying eggs when nests of these hosts are available, and such divergence may be further exaggerated by differences in timing of breeding among host races with similar habitat requirements. Host species accounted for a quarter of the variance in timing of breeding by the cuckoo. Common cuckoos reproduced at a similar, but narrower subset of dates as did possible hosts, showing that only a fraction of hosts with specific breeding dates were parasitized. Common cuckoo eggs laid in the 'right' kind of nests, phenotypically matching the eggs of the host, were laid later during the season than cuckoo eggs laid in the 'wrong' kind of nests where the eggs did not mimic those of the host. Pairs of sympatric cuckoo host races differed more in timing of breeding than pairs of allopatric host races, and pairs of cuckoo host races with similar breeding habitat differed more in breeding date than pairs of cuckoo host races with dissimilar habitat, as expected from reproductive character displacement. These findings are consistent with cuckoo host races being isolated by timing of breeding and habitat., 2011年03月, 24, 3, 676, 684, 研究論文（学術雑誌）, 10.1111/j.1420-9101.2010.02202.x

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• 査読あり, 英語, APPLIED ENTOMOLOGY AND ZOOLOGY, Dispersal of adult Asian citrus psyllid, Diaphorina citri Kuwayama (Homoptera: Psyllidae), the vector of citrus greening disease, in artificial release experiments, Youichi Kobori; Tadafumi Nakata; Yasuo Ohto; Fugo Takasu, Artificial release of marked adult Diaphorina citri, the insect vector of citrus greening disease, was performed in July 2007 (10,000 adults released, experiment 1) and October 2008 (1,000 adults released, experiment 2) to determine the association of the dispersal pattern with disease invasion risk. During the experimental periods, in experiment 1, the mean dispersal distances from the release point were 5-6 m and in experiment 2 they were 6-12 m. Further examination of the relationship between dispersal distance and season is needed. The number of released D. citri declined with increasing distance from the release point and did not change markedly with time. The center of distribution moved little during the experimental period. These results suggest that the adult D. citri barely moved once they had colonized a host plant within a few days after their release. Our results also suggest that the released D. citri moved with the wind. The diffusion coefficient was estimated at 7.23 from experiment 1, but random diffusion might be a poor descriptor of the dispersal of adult D. citri., 2011年02月, 46, 1, 27, 30, 研究論文（学術雑誌）, 10.1007/s13355-010-0004-z

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• 査読あり, 英語, POPULATION ECOLOGY, Modeling the consequence of increased host tolerance toward avian brood parasitism, Fugo Takasu; Csaba Moskat, Avian brood parasites greatly reduce the reproductive success of their hosts. Empirical studies have demonstrated that some hosts have evolved defenses against parasitism like an ability to recognize and reject parasitic eggs that are dissimilar to their own eggs. Detailed mechanisms of how hosts recognize parasitism still remain unknown, but recent studies have shown that the host's recognition, in many cases, is based on discordance of the eggs in a clutch, and that hosts are more error-prone when the nest is multiply parasitized, i.e., hosts tend to accept more multiple parasitism than single parasitism. In an area in Hungary, the great reed warbler Acrocephalus arundinaceus, one of the main hosts of the common cuckoo Cuculus canorus, is heavily parasitized and the parasitism rate has been kept at quite a high level for decades. Previous mathematical models suggest that such a high parasitism rate can be maintained because the focal host population behaves as a sink where few hosts can reproduce but immigration from outside replenishes the loss of host reproduction in the sink population. Here, we explore the consequences of the increased host tolerance towards multiple parasitism which has been overlooked in the previous studies using a simple model. Our model analysis shows that the increased host tolerance can dramatically contribute to both the parasite abundance and the parasitism rate being kept at a high level. We suggest that such a host behavior, combined with host immigration, can be an important factor responsible for the observed severe parasitism., 2011年01月, 53, 1, 187, 193, 研究論文（学術雑誌）, 10.1007/s10144-010-0221-x

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• 査読あり, 英語, PLOS ONE, Coevolution in Action: Disruptive Selection on Egg Colour in an Avian Brood Parasite and Its Host, Canchao Yang; Wei Liang; Yan Cai; Suhua Shi; Fugo Takasu; Anders P. Moller; Anton Antonov; Frode Fossoy; Arne Moksnes; Eivin Roskaft; Bard G. Stokke, Background: Trait polymorphism can evolve as a consequence of frequency-dependent selection. Coevolutionary interactions between hosts and parasites may lead to selection on both to evolve extreme phenotypes deviating from the norm, through disruptive selection. Methodology/Principal finding: Here, we show through detailed field studies and experimental procedures that the ashy-throated parrotbill (Paradoxornis alphonsianus) and its avian brood parasite, the common cuckoo (Cuculus canorus), have both evolved egg polymorphism manifested in discrete immaculate white, pale blue, and blue egg phenotypes within a single population. In this host-parasite system the most common egg colours were white and blue, with no significant difference in parasitism rates between hosts laying eggs of either colour. Furthermore, selection on parasites for countering the evolution of host egg types appears to be strong, since ashy-throated parrotbills have evolved rejection abilities for even partially mimetic eggs. Conclusions/Significance: The parrotbill-cuckoo system constitutes a clear outcome of disruptive selection on both host and parasite egg phenotypes driven by coevolution, due to the cost of parasitism in the host and by host defences in the parasite. The present study is to our knowledge the first to report the influence of disruptive selection on evolution of discrete phenotypes in both parasite and host traits in an avian brood parasitism system., 2010年05月, 5, 5, e10816. doi:10.1371/journal.po, 研究論文（学術雑誌）, 10.1371/journal.pone.0010816

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• 査読あり, 英語, BIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY, Adaptations in the common cuckoo (Cuculus canorus) to host eggs in a multiple-hosts system of brood parasitism, Fugo Takasu; Csaba Moskat; A. Roman Munoz; Sadao Imanishi; Hiroshi Nakamura, The common cuckoo Cuculus canorus parasitism greatly reduces the reproductive success of its hosts and imposes strong selection pressure for hosts to evolve defences against parasitism, such as the ability to recognize and reject dissimilar parasitic eggs, which, in turn, selects for better egg mimicry by the cuckoo. In the co-evolutionary interaction, however, it remains unknown how the cuckoo successfully expanded its range of host usage and how they developed egg mimicry. Most previous studies were conducted in areas where a very few number of host species (i.e. one or two at most) are sympatric with the cuckoo. Several host species, however, breed sympatric with the cuckoo and have been parasitized in the study site in Nagano, central Japan. Such a multiple-hosts system will provide valuable insights for understanding the cuckoo-hosts interactions in the past. In the present study, we report quantitative profiles of eggs based on spectrometer reflectance for four major host species and the corresponding cuckoo gentes. The hosts include the oriental reed warbler (Acrocephalus orientalis), bull-headed shrike (Lanius bucephalus), azure-winged magpie (Cyanopica cyana), and black-faced bunting (Emberiza spodocephala). We show that (1) egg morphs of each host and corresponding cuckoo gens can be categorized by two chromatic components of reflectance spectra and (2) there is a significant difference in a particular chroma component between hosts and the cuckoo. We suggest that the cuckoo parasitism in central Japan originated from parasitism on the black-faced bunting. (C) 2009 The Linnean Society of London, Biological Journal of the Linnean Society, 2009, 98, 291-300., 2009年10月, 98, 2, 291, 300, 研究論文（学術雑誌）
• 査読あり, 英語, POPULATION ECOLOGY, Individual-based modeling of the spread of pine wilt disease: vector beetle dispersal and the Allee effect, Fugo Takasu, Pine wilt disease is caused by the pinewood nematode Bursaphelenchus xylophilus, which is vectored by the Japanese pine sawyer beetle Monochamus alternatus. Due to their mutualistic relationship, according to which the nematode weakens and makes trees available for beetle reproduction and the beetle in turn carries and transmits the nematode to healthy pine trees, this disease has resulted in severe damage to pine trees in Japan in recent decades. Previous studies have worked on modeling of population dynamics of the vector beetle and the pine tree to explore spatial expansion of the disease using an integro-difference equation with a dispersal kernel that describes beetle mobility over space. In this paper, I revisit these previous models but retaining individuality: by considering mechanistic interactions at the individual level it is shown that the Allee effect, an increasing per-capita growth rate as population abundance increases, can arise in the beetle dynamics because of the necessity for beetles to contact pine trees at least twice to reproduce successfully. The incubation period after which a tree contacted by a first beetle becomes ready for beetle oviposition by later beetles is crucial for the emergence of this Allee effect. It is also shown, however, that the strength of this Allee effect depends strongly on biological mechanistic properties, especially on beetle mobility. Realistic individual-based modeling highlights the importance of how spatial scales are dealt with in mathematical models. The link between mechanistic individual-based modeling and conventional analytical approaches is also discussed., 2009年07月, 51, 3, 399, 409, 研究論文（学術雑誌）, 10.1007/s10144-009-0145-5

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• 査読あり, 英語, EVOLUTION, The importance of clutch characteristics and learning for antiparasite adaptations in hosts of avian brood parasites, Bard G. Stokke; Fugo Takasu; Arne Moksnes; Eivin Roskaft, There is considerable variation in rejection rates of parasitic eggs among hosts of avian brood parasites. In this article, we develop a model that can be used to predict host egg rejection behavior in brood parasite-host systems in general, by considering both intra- and interclutch variation in host egg appearance; clutch characteristics that may be important in calculating the fitness of individuals adopting rejecter or acceptor strategies. In addition, we consider the importance of learning the appearance of own eggs during the first breeding attempt and host probability of survival between breeding seasons on evolution of rejection behavior. Based on this model we can predict at which level of parasitism fitness of rejecter individuals is higher than that of acceptor individuals and vice versa. The model analyses show that variation in egg appearance can be a key factor for the evolution of host defense against parasitism. In more detail, analyses show that we should expect to find a prolonged learning period only in hosts that have a high intraclutch variation in egg appearance, because such hosts may potentially experience high costs in terms of recognition errors. Furthermore, learning is in general more adaptive in parasite-host systems in which hosts do have some reproductive success even when parasitized, and when parasitism rates are moderate. By including variables that have not been considered in previous models, our model represents a useful tool in investigations of host rejection behavior in various host-parasite systems., 2007年09月, 61, 9, 2212, 2228
• 査読あり, 英語, AUK, Nest light environment and the potential risk of common cuckoo (Cuculus canorus) parasitism, A. Roman Munoz; Maria Altamirano; Fugo Takasu; Hiroshi Nakamura, Brood parasitism represents a significant cost in reproduction; thus, natural selection should favor the evolution of host defenses, which in turn may favor evolution of more sophisticated techniques by the parasite to overcome host defenses. These host defenses include egg rejection, attacking parasites near the nest, and avoiding parasitism by concealing nest sites. In all these antiparasitism strategies, nest light environment may play an important role. In the present study, the risk of Common Cuckoo (Cuculus canorus) parasitism for the Great Reed Warbler (Acrocephalus arundinaceus) was modeled in relation to the in situ nest light environment, from far ultraviolet (UV) to infrared (IR) radiation (280-1,100 nm), and nest situation and structure. The percentage of photosynthetically active radiation (PAR) plus IR radiation (400-1,100 nm) falling on the nest, maximum nest width, and distance between the nest and the nearest active conspecific neighbor were significantly related to the risk of parasitism. Photosynthetically active radiation alone explained 65% of variation in parasitism risk in the final model. Although solar radiation levels in nests were low (<4%. for UV-B and UV-A radiation, 5% for PAR, and 22% for PAR plus IR radiation when cloudless), UV-B, UV-A, and visible-plus-IR radiation levels were significantly lower in nonparasitized nests. These findings provide the first evidence of a relationship between parasitism risk and nest concealment related to microhabitat light environment, with brighter nests suffering a higher risk of parasitism., 2007年04月, 124, 2, 619, 627, 研究論文（学術雑誌）
• 査読あり, 英語, BEHAVIORAL ECOLOGY, Importance of spatial habitat structure on establishment of host defenses against brood parasitism, Eivin Roskaft; Fugo Takasu; Arne Moksnes; Bard Gunnar Stokke, We used metapopulation dynamics to develop a mathematical simulation model for brood parasites and their hosts in order to investigate the validity of the "spatial habitat structure hypothesis," which states that a low level of parasite egg rejection in host populations is due to the immigration of acceptor individuals from nonparasitized populations. In our model, we varied dispersal rate and the relative carrying capacity of host individuals in parasitized and unparasitized patches. When both the relative carrying capacity in the parasite-free patch and the dispersal rate increase, the nonparasitized patch will provide more acceptor individuals to the parasite-prone patch. As the relative carrying capacity in the parasite-free patch increases, the equilibrium frequency of rejecters both in the parasite-prone and in the parasite-free patch decreases toward zero for intermediate levels of the dispersal rate. Although the rejecter strategy is more adaptive than the acceptor strategy in the parasite-prone patch, large numbers of acceptors are produced in the parasite-free patch dispersing to the parasitized patch. As the number of individuals in the parasite-free patch increases, parasitism rate can be maintained stable at a high equilibrium level in the parasite-prone patch., 2006年09月, 17, 5, 700, 708, 研究論文（学術雑誌）, 10.1093/beheco/ark019

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• 査読あり, 英語, Ecological Research, How does stochasticity in colonization accelerate the speed of invasion in a cellular automaton model?, 高須夫悟, 2006年03月, 21, 334-354
• 査読あり, 英語, Ornithological Science, A theoretical consideration on coevolutionary interactions between avian brood parasites and their hosts, Fugo Takasu, It has been suggested that parasitic interactions in general result in coevolutionary arms races where parasites and hosts evolve adaptive behaviours and traits to maximize their fitness in a conflicting manner. Avian brood parasitism provides an ideal system for the study of such coevolutionary interactions. In this paper I show and discuss possible consequences of the coevolutionary arms race inherent in avian brood parasitism, especially focusing on egg appearance, a key factor for the reproduction of both hosts and parasites. In such an arms race, hosts evolve the ability to recognize and hence to reject dissimilar parasitic eggs, while parasites counter host defences by more closely mimicking their eggs. Egg mimicry by parasites might then be de-stabilized by hosts changing the appearance of their eggs, thus exposing the mimics. The evolutionary trajectory of the arms race varies depending on the specific detailed mode of interaction between parasite and host individuals. Mathematical modeling, as an important parallel approach to empirical study, helps point the way for further study of avian brood parasitism so as to better understand coevolution in general. © 2005, The Ornithological Society of Japan. All rights reserved., 2005年, 4, 1, 65, 72, 研究論文（学術雑誌）, 10.2326/osj.4.65

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• 査読無し, 英語, POPULATION ECOLOGY, How many eggs should be laid in one's own nest and others' in intra-specific brood parasitism?, F Takasu, Recent field studies have demonstrated that many bird species practice intra-specific brood parasitism. They lay eggs in the nests of other individuals of the same species, let the foster parents rear their offspring and avoid the cost of parental care. It has been shown that many birds, including starlings, swallows and geese, practice intra-specific brood parasitism in various forms. Intra-specific brood parasitism can be viewed in terms of optimal resource allocation: how many eggs should be put in the nests of other individuals under the risk of being parasitized by others. The situation here is a "game", because the fitness of a parasitic individual depends on how other individuals behave (how many individuals practice parasitism and to what extent). The ecology of intra-specific brood parasitism has been investigated extensively by field ornithologists recently and it is full of material for modeling population/evolutionary biology. In this paper, I present a simple individual-based model to challenge the resource allocation problem in intra-specific brood parasitism. Previous theoretical studies of intra-specific brood parasitism have been based on ESS or quantitative genetics models, where a population is implicitly assumed to be homogeneous and the distribution form of the trait being studied (the allocation rate or the number of eggs laid parasitically) is inherently monomorphic. This paper aims to explore the evolution of intra-specific brood parasitism without these restrictions. In the model, an individual is assigned a strategy, an allocation ratio of eggs that are laid parasitically in the nests of other individuals, and the strategy is inherited by offspring either asexually or sexually. Based on the simulation analysis, the evolution of the allocation rate (the extent of intra-specific brood parasitism) is discussed. The extension of this model to a tractable analytical model is also discussed., 2004年12月, 46, 3, 221, 229, 研究論文（学術雑誌）, 10.1007/s10144-004-0192-x

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• 査読無し, 英語, Proceeding of the Fourth International Congress of Nematology, Modelling the range expansion of pine wilt disease, Yukie Mimura; Kohkichi Kawasaki; Fugo Takasu; Katsumi Togashi; Nanako Shigesada, Pine wilt disease is caused by pinewood nematode (PWN), Bursaphelenchus xylophilus. The pine sawyer beetle, Monochamus alternatus, in a relationship of obligatory mutalism, vectors this nematode. For more than a century pine wilt disease has spread throughout much of Japan, and in recent times intense management efforts have been taken. These management strategies, however, have not been overly efficient. In this study, we have constructed a mathematical model to describe the spatial-temporal spread of pine wilt disease as a way to investigate the dependency of the range expansion speed (RES) of the disease on the eradication of the vector insect and the patch size of pine stands. We assume that beetles are eradicated at a rate theta only where the infected pine density is larger than a threshold, H-T and investigate how the range expansion speed changes with varying values of theta and H-T. Moreover, we change the patch size of pine stands, with the total area of pine stands being kept constant. The main results are as follows: i) as the eradication rate, theta, increases, the RES initially decreases gradually and then suddenly drops to zero at a certain value of theta; ii) it is impossible to eradicate the disease regardless of the value of theta, when the threshold of the infected pine density, H-T, exceeds a certain value; iii) as H-T decreases, the RES initially shows a gradual decrease and then suddenly drops to zero at a certain value of H-T; iv) it is impossible to eradicate pine wilt disease regardless of the value of H-T, when theta is below a certain value; and v) as the patch size of pine stands becomes larger, the RES increases., 2004年, 2, 843, 853, 研究論文（国際会議プロシーディングス）
• 査読無し, 英語, JOURNAL OF ETHOLOGY, Survival and anti-parasite defense in a host metapopulation under heavy brood parasitism: a source-sink dynamic model, L Barabas; B Gilicze; F Takasu; C Moskat, The obligate brood parasite common cuckoo Cuculus canorus, widespread in Eurasia, occasionally reaches a high parasitism rate (over 20%), which usually exists only for a short period of time and in cases of new parasitism. Recent results from Hungary proved that a remarkably high parasitism rate (50-66%) can also be maintained constantly for several decades. In this paradoxical situation the reproductive success of the strongly exploited host population is lower than would be necessary for self-reproduction. We developed a model for a hypothetical host-brood parasite system that demonstrated that immigration of naive individuals from a highly reproductive ("source") host population might explain the survival of the highly parasitized ("sink") population. Our results also showed the possibility of maintaining the high parasitism rate and the imperfection of the host's counter-adaptation against the brood parasite over a longer period. Gene flow was necessary to maintain both the acceptor genes and the non-mimetic cuckoo eggs in heavy parasitism. When the immigration rate was low (1-2%), an early expansion of the mimetic cuckoos was followed by a spread of anti-parasite defense, and consequently, the parasitism rate stabilized at a lower, but still relatively high level of about 45-60%., 2004年, 22, 2, 143, 151, 研究論文（学術雑誌）, 10.1007/s10164-003-0114-y

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• 査読無し, 英語, POPULATION ECOLOGY, How does spatio-temporal disturbance influence species diversity in a hierarchical competitive system? Prospective order of species coexistence and extinction （共著）, 高須夫悟, To address how habitat destruction and hierarchical competition among species affect the spatio-temporal dynamics of a multi-species community, we present a compartment model in which multiple species undergo dispersal and competitive interactions in a patchy habitat arranged in a two-dimensional lattice. We assume that disturbances are periodically imposed on some parts of the lattice in a block, followed by a period free of disturbance. For convenience, species are ranked in order of competitive ability. We further assume that the intrinsic growth rate of species i, epsilon(i), and the dispersal ability, D-i, increase in decreasing order of rank. Our model can analytically determine the exact number of surviving species when disturbance is absent. In the presence of disturbance, we numerically examine how spatio-temporal changes in environmental heterogeneity affect species coexistence and extinction, for the case in which the value of epsilon(i)/D-i monotonically increases or decreases with rank. The results demonstrate that (1) when the interspecific competition is smaller than the intraspecific competition, we can provide predictions on the prospective order of species to be driven extinct and the order of potential species to revive with increasing extents of disturbance; (2) when the interspecific competition is stronger than intraspecific competition, a small difference in the disturbance level can lead to drastic changes in the species composition, their densities and the order of species extinction. In addition, comparison with other similar models reveals that differences in species interaction in local population dynamics critically affect the disturbance-mediated species diversity., 2003年12月, 45, 3, 239, 247, 研究論文（学術雑誌）, 10.1007/s10144-003-0165-5

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• 査読無し, 英語, EVOLUTIONARY ECOLOGY RESEARCH, Co-evolutionary dynamics of egg appearance in avian brood parasitism, F Takasu, In avian brood parasitism, interactions between parasites and their hosts lead to a co-evolutionary process called an arms race. Field studies have shown that many host species have evolved an ability to recognize and reject parasite eggs that look unlike their own and that some parasites lay eggs of sophisticated mimicry. Egg appearance is a crucial factor that determines the reproductive success both of the parasites and their hosts in the arms race. The appearance of eggs, however, is a quantitative trait and the variation within a population could critically affect the dynamics of the arms race; parasite individuals that lay eggs more similar to those of the host are more likely to reproduce successfully, whereas host individuals that lay eggs more unlike those of the parasite have a better chance of rejecting parasitism and reproducing, which would de-stabilize the parasites' good mimicry. To explore the arms race for egg appearance, I constructed a model described by an integro-difference equation. The temporal change of the 'distributions' of egg appearance along a continuous spectrum was analysed both for the parasite and host populations. The model analyses show that (1) a conventional view of an arms race-'parasites chasing their hosts escaping from the parasites'-is realized in the early stage of the dynamics, but (2) the distributions of egg appearance finally converge to discrete point-distributions (polymorphism) even when any continuous distributions are used as the initial state. The latter might be relevant to the maintenance of polymorphism of egg appearance. Based on the model analysis, I discuss the implications of this model for general (co)evolutionary processes for quantitative traits and suggest a new modelling framework to account for such processes., 2003年03月, 5, 3, 345, 362, 研究論文（学術雑誌）
• 査読無し, その他, In: Morphogenesis and Pattern Formation in Biological Systems: Experiments and Models (eds. T.Sekimura, S.Noji, N.Ueno & P.K.Maini). Springer-Verlag Tokyo., Biological invasion into periodically fragmented environments: A diffusion-reaction model., N. Shigesada; N. Kinezaki; K. Kawasaki; F. Takasu, (2003), 2003年, 215, 222
• 査読あり, 英語, Theoretical Population Biology, Modeling biological invasions into periodically fragmented environments（共著）, 高須夫悟, 2003年, 64, 291-302
• 査読無し, 英語, Journal of Theoretical Biology, Recurrent Habitat Disturbance and Species Diversity in a Multiple-Competitive Species System（共著）, 高須夫悟, To address how species interactions, dispersal and environmental disturbances interplay to affect the spatial distribution and diversity of species, we present a compartment model in which multiple species undergo competitive interaction of Lotka-Volterra type in a patchy environment arranged in a square lattice. Dispersal of species occurs between adjacent patches. Disturbances are periodically imposed on a central part of the environment in a belt-like block or an island-like block of various sizes where each species is killed for a certain time interval and then allowed to recover for the rest of a disturbance cycle. We deal with a case in which the local population dynamics within each patch is analytically determinable and has multiple locally stable equilibrium states in the absence of environmental disturbance. We further assume a trade-off between the reproductive rate of species and its dispersal ability. With these settings, we numerically examine how the spatio-temporal distributions of species are affected by changes in the pattern, size and duration of disturbances. The results demonstrate that: (1) in the undisturbed area, environmental disturbances could generate spatially segregated distributions of species; (2) in the disturbed area, species with higher dispersal abilities quickly invade and preferentially recover their population during the post-disturbance period, being temporarily relieved of competition from other species. These mechanisms collectively lead to increased species diversity in the whole habitat, functioning best when both the size and duration of disturbances are intermediate. In particular, the belt-like disturbance is more effective than the island-like disturbance in sustaining spatial heterogeneity for a wider range of duration of disturbance. (C) 2002 Elsevier Science Ltd. All rights reserved., 2002年05月, 216, 2, 123, 138, 研究論文（学術雑誌）, 10.1006/jtbi.2002.2554

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• 査読無し, 英語, Behavioral Ecology, Modeling spawning strategy for sex change under social control in haremic angelfishes（共著）, 高須夫悟, In haremic angelfishes where protogynous (female to male) sex change is favored, females have been reported to adopt several tactics for earlier sex change on the basis of a trade-off between reproduction and growth, or survivorship. A recent field study on Centropyge ferrugatus revealed that females reduce spawning frequency in competition with similar-sized neighbors for social dominance. To evaluate the optimal spawning strategy taken by haremic fishes, we developed an evolutionarily stable strategy model that focuses on their life history and social structure based on field data of C. ferrugatus. The results of the analysis predict that the spawning frequency will be low when the mortality rate of females is high compared with males, the harem size is large, and there is a moderate degree of social control. Our model further predicts conditions under which females completely stop spawning, as if they have become bachelors. Thus, the regulated spawning frequency may be taken as a strategy to optimize the reproductive success of an individual in response to the available choices for sex change, social control, and environmental conditions. Social control would also play an important role in sex change in many other haremic species., 2002年01月, 13, 1, 75, 82, 研究論文（学術雑誌）
• 査読あり, 英語, JAPAN JOURNAL OF INDUSTRIAL AND APPLIED MATHEMATICS, Diffusive waves, dynamical stabilization and spatio-temporal chaos in a community of three competitive species（共著）, 高須夫悟, The spatio-temporal dynamics of three competitive species is considered. Mathematically, the community is described by a system of partial differential equations of Lotka-Volterra type. The properties of the system are investigated both numerically and analytically. We show that for finite initial conditions the dynamics of the system is typically reduced to a succession of travelling diffusive waves, some of which demonstrate rather an unusual behaviour. Particularly, a locally unstable equilibrium can become stable in the wake of a diffusive front. After propagation of the waves, the domain is invaded by irregular spatiotemporal population oscillations that can be classified as spatio-temporal chaos., 2001年06月, 18, 2, 459, 481, 研究論文（学術雑誌）
• 査読あり, 英語, Protection of World Forests from Insect Pests: Advances in Research (eds. H. Evans & A. Liebhold) IUFRO World Series, Spatial spread of pine wilt disease : modeling the dispersal distance distribution of the pine sawyer beetle, Monochamus alfernatus（共著）, 高須夫悟, 2001年, 11, 79-85
• 査読あり, 英語, BULLETIN OF MARINE SCIENCE, Morphological plasticity in the coral Porites sillimaniani and its adaptive significance(共著), 高須夫悟, The whole-colony morphology of the coral, Porites sillimaniani, varies dramatically in accordance with light intensity from plate-like shape to branching shape. To determine whether the variation is based on genetic difference or phenotypic plasticity, we conducted a field experiment by transplanting coral fragments taken from seven plate-like colonies to different light conditions. The fragments that transplanted to the high-light condition started to have branches in 8 mo period of the experiment, whereas those to the low-light condition remained to be flat. This result suggests that the morphological variation is the phenotypic plasticity in response to light availability. To examine the adaptive significance of this plasticity a simple mathematical model of coral shape is constructed in which the number of branches, their angles and lengths are morphological parameters. The circumference of the model coral is assumed to be uniformly covered with polyps. Each polyp survives if its light flux is larger than a certain threshold value. The optimal morphology that can support a maximum number of viable polyps is calculated for a given light intensity. The optimal coral shape changes with light intensity, which agrees qualitatively with the observation of P. sillimaniani colony in natural habitats., 2000年01月, 66, 1, 225, 239, 研究論文（学術雑誌）
• 査読あり, 英語, Biological Invasions, Modeling the range expansion of an introduced tree disease（共著）, 高須夫悟, Pine wilt disease is caused by the introduced pinewood nematode, Bursaphelenchus xylophilus, for which the vector is the pine sawyer beetle, Monochamus alternatus. Native Japanese pines, black pine “Pinus thunbergii” and red pine “P. densiflora”, are extremely sensitive to the nematode's infection, and the parasite has been expanding nationwide in the last few decades, despite intensive control efforts. To understand the parasite's range expansion in Japan, we modeled the dynamics of the pines and the beetle that disperses the nematode, using an integro-difference equation in a one-dimensional space. Based on field data collected in Japan, we investigated the dependence of the parasite's rate of range expansion on the eradication rate of the beetle, the initial pine density, and the beetle dispersal ability. Our model predicts several results. “1” The Allee Effect operates on beetle reproduction, and consequently the parasite cannot invade a pine stand, once the beetle density decreases below a threshold. “2” The distribution of the dispersal distance of the beetles critically affects the expansion rate of the disease. As the fraction of the beetles that travel over long distance increases from zero, the range expansion accelerates sharply. “3” However, too frequent long-range dispersal results in a failure of the parasite invasion due to the Allee Effect, suggesting the importance of correctly assessing the beetle's mobility to predict the speed of range expansion of the parasite. “4” As the eradication rate is increased, the range expansion speed decreases gradually at first and suddenly drops to zero at a specific value of the eradication rate., 2000年, 2, 2, 141, 150, 研究論文（学術雑誌）, 10.1023/A:1010048725497

  DOI URL
• 査読あり, 日本語, 日本生態学会誌 50, 一般社団法人 日本生態学会, マツ枯れシステムのダイナミクスと大域的伝播の数理解析（共著）, 山本 奈美子; 高須 夫悟; 川崎 廣吉; 富樫 一巳; 岸 洋一; 重定 南奈子, 2000年, 50, 3, 269-276, 276, 10.18960/seitai.50.3_269

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• 査読あり, 英語, ECOLOGY, Modeling the spread of pine wilt disease caused by nematodes with pine sawyers as vector（共著）, 高須夫悟, An epidemic of pine wilt disease has been spreading in wide areas of Japan for nearly a century. The disease is caused by the pinewood nematode, Bursaphelenchus xylophilus, with the pine sawyer, Monochamus alternatus, as vector. The spread of disease is facilitated by an obligatory mutualism between the nematode and the pine sawyer: the pine sawyer helps the nematode transmit to a new host tree, while the nematode supplies the pine sawyer with newly killed trees on which to lay eggs. We present a mathematical model to describe the host-vector interaction between pines and pine sawyers carrying nematodes, on the basis of detailed data on the population dynamics of pine sawyers and the incidence of pine wilt disease at a study site located on the northwest coast of Japan. We used the model to simulate the dynamics of the disease and predict how the epidemic could be controlled by eradication of the pine sawyer, The main results are as follows: (1) There is a minimum pine density below which the disease always fails in invasion. However, even if the pine density exceeds this minimum, the disease fails in invasion due to the Allee effect when the density of pine sawyers is very low. (2) The: minimum pine density increases disproportionately with increase in the eradication rate. (3) The probability that a healthy tree will escape from infection until the epidemic dies out decreases sharply with increase in the initial pine density or the initial density of pine sawyers., 1999年07月, 80, 5, 1691, 1702, 研究論文（学術雑誌）
• 査読あり, 英語, Biological Invasions of Ecosystem by Pests and Beneficial organisms, NIAES Series 3, Mathematical models for biological invasions-competition for open spaces（共著）, 高須夫悟, 1999年, 78-87
• 査読あり, 英語, 宇宙生物科学 = Biological sciences in space, Population dynamics of nitrifying bacteria in an aquatic ecosystem(共著), 高須夫悟, 1999年, 13, 4, 333-340, 195
• 査読無し, 英語, EVOLUTIONARY ECOLOGY, Modelling the arms race in avian brood parasitism, F Takasu, In brood parasitism, interactions between a parasite and its host lead to a co-evolutionary process called an arms race, in which evolutionary progress on one side provokes a further response on the other side. The host evolves defensive means to reduce the impact of parasitism, while the parasite evolves means to counter the host's defence. To gain insights into the co-evolutionary process of the arms race, a model is developed and analysed, in which the host's defence and the parasite's counterdefence are assumed to be genetically determined. First, the effect of parasite counterdefence on host defence is analysed. I show that parasite counterdefence can critically affect the establishment of host defence, giving rise to three situations in the equilibrium state: The host shows (1) no defence, (2) an intermediate level of defence or (3) perfect defence. Based on these results, the evolution of parasite counterdefence is considered in connection with host defence. It is suggested that the parasite can evolve counterdefence to a certain degree, but once it has established counterdefence beyond this, the host gives up its defence against parasitism provided the defence entails some cost to perform. Dynamic aspects of selection pressure are crucial for these results. Based on these results, I propose a hypothetical evolutionary sequence in the arms race, along which interactions between the host and parasite proceed., 1998年11月, 12, 8, 969, 987, 研究論文（学術雑誌）
• 査読無し, 英語, AMERICAN NATURALIST, Why do all host species not show defense against avian brood parasitism: Evolutionary lag or equilibrium?, F Takasu, Avian brood parasitism reduces the reproductive success of hosts and is therefore expected to select for host defenses against parasitism, such as an ability to reject parasitic eggs. Field studies have shown that some hosts recognize and reject parasitism, whereas others do not, and the degree of the defense varies from population to population. One long-standing debate concentrates on the differences in the distribution of host defenses observed in hosts parasitized by the brown-headed cowbird and the common cuckoo. The cowbird's hosts show either few or nearly perfect defenses, whereas the cuckoo's hosts have defenses varying from none to complete, with most falling in between the two extremes. To explore the mechanisms underlying this pattern, I constructed a mathematical model in which host defense is assumed to be genetically determined and analyzed how the host defense is established under parasitic pressure. The model shows that differences in the defense-level distribution can be attributed to the difference in the parasite's breeding strategy, generalized or specialized: hosts parasitized by generalists show perfect, none, or intermediate levels of the defense depending on the host abundances, whereas hosts parasitized by specialists always exhibit either none or intermediate levels of the defense if the parasite lacks counterdefenses such as egg mimicry. This result provides a testable explanation for the existence of accepter species of the brown-headed cowbird, which might reconcile the previously conflicting hypotheses., 1998年02月, 151, 2, 193, 205, 研究論文（学術雑誌）
• 査読あり, 英語, Forma, Simulation study of Stratitied Diffusion Model（共著）, 高須夫悟; 川崎廣吉; 重定南奈子, 1997年, 12, 2, 167-175, 175
• 査読あり, 日本語, 日本生態学会誌, 一般社団法人 日本生態学会, 行動と共進化－托卵鳥とその宿主, 高須夫悟, 1995年, 45, 2, 191-197, 197, 10.18960/seitai.45.2_191

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• 査読あり, 英語, AMERICAN NATURALIST, Modeling the population dynamics of a cuckoo-host association and the evolution of host defenses（共著）, 高須夫悟, Cuckoo parasitism in Nagano Prefecture in Japan has shown dramatic changes in the parasitism rate, host usage by the cuckoo, and defensive behavior of hosts during the past 60 yr. To gain insights into these phenomena, we model the population dynamics of a cuckoo-host association together with the population genetics of a rejecter gene in the host population. Analysis shows that both the dynamical change in the host-parasite association and the establishment of the host's counteradaptation crucially depend on the product of two factors, the carrying capacity of the host and cuckoo's searching efficiency. When the product is less than a critical value, the host population cannot evolve a counteradaptation even if parasitized by the cuckoo. Hence, the lack of counteradaptation does not necessarily imply that the host population only recently has become parasitized. As the product becomes larger, the rejection behavior will be eventually established at higher levels in the host population. In this case, the spreading of rejection behavior is very fast, which suggests that the cuckoo-host association reaches an equilibrium state within a relatively short period. These results make possible new interpretations of several circumstances reported about cuckoo-host associations., 1993年11月, 142, 5, 819, 839, 研究論文（学術雑誌）
• 査読あり, 英語, Ornithological Science, Egg Pattern Mimicry in Avian Brood Parasitism Assessed Using Local Image Descriptors and Human-Eyes, Huu Ton Le; Doanh Nguyen-Ngoc; Hoang Tung Tran; Anh Tuan Giang; Edourd Amouroux; Antonio-Román Muñoz; Fugo Takasu, 2022年07月29日, 21, 2, 研究論文（学術雑誌）, 10.2326/osj.21.189

  DOI URL
• 査読あり, 英語, Frontiers in Plant Science, Simulating Pine Wilt Disease Dispersal With an Individual-Based Model Incorporating Individual Movement Patterns of Vector Beetles, Chunlei Xia; Tae-Soo Chon; Fugo Takasu; Won Il Choi; Young-Seuk Park, Individual movements of the insect vector pine sawyer beetles were incorporated into an individual-based model (IBM) to elucidate the dispersal of pine wilt disease (PWD) and demonstrate the effects of control practices. The model results were compared with the spatial data of infested pine trees in the Gijang-gun area of Busan, Republic of Korea. Step functions with long- and middle-distance movements of individual beetles effectively established symptomatic and asymptomatic trees for the dispersal of PWD. Pair correlations and pairwise distances were suitable for evaluating PWD dispersal between model results and field data at short and long scales, respectively. The accordance between model and field data was observed in infestation rates at 0.08 and 0.09 and asymptomatic rates at 0.16–0.17 for disease dispersal. Eradication radii longer than 20 m would effectively control PWD dispersal for symptomatic transmission and 20–40 m for asymptomatic transmission. However, the longer eradication radii were more effective at controlling PWD. Therefore, to maximize control effects, a longer radius of at least 40 m is recommended for clear-cutting eradication. The IBM of individual movement patterns provided practical information on interlinking the levels of individuals and populations and could contribute to the monitoring and management of forest pests where individual movement is important for population dispersal., 2022年05月23日, 13, 研究論文（学術雑誌）, 10.3389/fpls.2022.886867

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• 査読あり, 英語, Journal of Theoretical Biology, Spatial metapopulation dynamics with local and global colonization, Le Dieu Huong; Nguyen Trong Hieu; Fugo Takasu, 2023年09月, 572, 111579, 111579, 研究論文（学術雑誌）, 10.1016/j.jtbi.2023.111579

  DOI URL共同研究・競争的資金等URL

MISC

• 査読無し, 日本語, 生物科学, 日本生物科学者協会, フィールド研究と数理モデル研究, 高須夫悟, 2003年01月, 54, 2, 111-118, 118

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• 査読無し, 英語, Proceedings of 22nd International Ormthological Congress Adams, N-J. & Slotow, R. H. (eds.), The role of theoretical models explaining the relationships between brood parasites and their hosts, 高須夫悟, 1999年, 3146-3164
• その他, 日本応用動物昆虫学会大会講演要旨, 個体ベースモデルによる激発地におけるカンキツグリーニング病防除手段の検討, 小堀陽一; 高須夫悟; 大藤泰雄, 2012年, 56th
• その他, 日本数理生物学会大会講演要旨集, 個体ベースモデルを活用したカンキツグリーニング病の防除技術開発, 小堀陽一; 高須夫悟; 大藤泰雄, 2012年, 22nd
• その他, 日本応用動物昆虫学会大会講演要旨, カンキツグリーニング病の虫媒伝搬による侵入と感染拡大のリスク評価, 小堀陽一; 中田唯文; 大藤泰雄; 高須夫悟, 2010年, 54th
• 日本語, 数理解析研究所講究録, 京都大学, 個体性を維持したモデリング (生物現象に対するモデリングの数理), 高須 夫悟, 2009年06月, 1653, 1, 1

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• 英語, 数理解析研究所講究録, 京都大学, A MATHEMATICAL MODEL OF THE EVOLUTION OF HOST DEFENSIVE BEHAVIOR IN CUCKOO - HOST ASSOCIATIONS(Mathematical Topics in Biology), 高須 夫悟; 川崎 廣吉; コーエン ジョエル[他], 1993年03月, 827, 146, 155

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• 日本語, 情報処理学会研究報告数理モデル化と問題解決（MPS）, 一般社団法人情報処理学会, 生物の伝播に関する確率論的積分差分モデル, 木村 美紀; 川崎 廣吉; 高須 夫悟; 重定 南奈子, 侵入生物の分布域拡大過程を記述するモデルの一つにKot et al.の積分差分方程式がある。しかし、この式は決定論的モデルであり、確率的な効果は全く考慮されていないという問題を含んでいる。そこで、増殖、分散ともに確率的に起こるモデルを構築し、確率的効果が伝播速度に及ぼす効果について考察した。数値計算を行った結果、確率論的モデルは決定論的モデルに比べて、伝播速度が70?80％程度に大きく減少することが判明した。確率論的モデルの遅れの原因が増殖の確率性によるものか分散の確率性によるものかを明らかにし、更に決定論的モデルにアリー効果を加えることにより、アリー効果が速度に及ぼす効果を求め対応する確率論的モデルとの関係を議論する。Organisms expand their distribution area, while undergoing dispersal and reproduction. One model describing such spread of organisms is given by the integro-difference equation. In this study, we consider a stochastic model that incorporates stochasticity in both reproduction and dispersal processes within the framework of the deterministic model. We performed computer simulations of this stochastic model and found that the speed in the stochastic model is about 70縲鰀80% less than that in the corresponding deterministic model. We distinguished the stochasticity in growth from that in dispersal on the overall speed. As a result, we found that the speed scarcely changes with the degree of stochasticity in reproduction. Thus we conclude that the delay in speed is caused mainly by stochastic dispersal., 2004年05月07日, 2004, 42, 29, 30

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• 日本語, 情報処理学会研究報告数理モデル化と問題解決（MPS）, 一般社団法人情報処理学会, 量的形質の進化に関する個体群ベースモデル, 山田 聡美; 高須 夫悟; 重定 南奈子, 量的形質は一般的に、個々の関与が小さな複数の遺伝子座が関係して発現すると考えられる。本研究では形質の進化が個体群動態に及ばす影響に注目する。個体群動態に影響を及ぼしうる量的形質が進化する場合であり、特に注目する形質が有性的に遺伝する場合を想定し、数理モデルによる解析を行う。 量的形質の遺伝に関してはいくつかの理論モデルが提出されているがその多くは理想的な状況の下で注目する量的形質に関する決定論的なダイナミクスに基づくものである。本研究では、複数遺伝子座が相加的に関与して量的形質が発現するという仮定の下で、確率論的な個体ベースモデルシミュレーションを行い、従来の決定論的なダイナミクスに基づくモデルとの比較を行う。A heritable quantitative trait in general is an expression that results from accumulated small contributions of a certain number of genes at multiple loci. In this study, we analyze both the evolution of a quantitative trait and, the consequence of it on the population dynamics. We assume a population where the trait in focus could be either the intrinsic growth rate or the carrying capacity and investigate how the evolution of the trait affects properties of the population dynamics. Furthermore we are curious to know what difference emerges when compared with a realistic model based on stochastic individual-based model. We construct IBM and analyze it by simulation and then derive a deterministic dynamics corresponding to the IBM. The difference between the two models is discussed., 2004年05月07日, 2004, 42, 31, 32

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• 日本語, 情報処理学会研究報告数理モデル化と問題解決（MPS）, 一般社団法人情報処理学会, 帯状分断環境における侵入生物の伝播モデル, 杵崎 のり子; 川崎 廣吉; 高須 夫悟; 重定 南奈子, 近年，道路や建物などの人為的な環境攪乱による生物の生息域分断化が種の存続に大きな影響を与え，不均質環境における生物の存続や侵入の問題は保全生態学観点からも極めて重要な課題となっている．そこで本研究では，不均質環境に対する生物の侵入問題に対して解析的なアプローチを試みた．つまり，帯状の好適環境と不適環境とが周期的にあらわれる２次元帯状分断環境を取り上げ，これに拡張Fisher モデルを適用して分布拡大過程の数学的な解析を行った．特に，少数の生物がある点に侵入した場合に帯状分断環境を伝播する速度と分布拡大パターンを解析的に描く手法を提出する．Environments for living organisms are often fragmented by natural or artificial habitat destruction. To simulate the range expansion of a single species in such a heterogeneous environment, we present a diffusion-reaction equation in which the rates of diffusion and reproduction periodically fluctuate between favorable and unfavorable habitats arranged in a striped pattern. Using this model, we derive a mathematical formula for the invasion speed together with the spatio-temporal pattern of range expansion., 2001年05月10日, 2001, 37, 19, 22

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• 日本語, 情報処理学会研究報告数理モデル化と問題解決（MPS）, 一般社団法人情報処理学会, Individual Based Modelを用いた アユのなわばり形成に関する研究, 奥野 由美子; 高須 夫悟, アユは日本を代表する川魚であり、排他的な領域を確保する所謂なわばり行動をと ることで有名である。しかし。集団密度が高い場合、なわばりを持てない放浪個体が 出現するなど、すべての個体がなわばりを確保するわけではない。また、なわばりの 面積は集団密度に関わらず、平均して１平方メートルであるが、この面積に含まれる 餌（藻）の量は１個体を養うには十分すぎることから、不必要に広いなわばりを確保 する行動がアユの集団中にどのように進化してきたかについては不明な点が多い。本 研究では、各個体の動きや相互作用をIndividual Based Modelを用いて再現し、なわ ばり行動の進化的意味を探るためにコンピュータシミュレーションによる解析を行な った。Game fish Ayu is a fresh water fish in Japan and famous for forming exclusive territory for foraging during the growth period. But not all individuals can own territory when the population density is high. The territory in average covers about 1 ・ irrespective of the population density, and it contains enough amount of algate, the food resource of Ayu, to sustain the owner of the territory.The evolutionary origin of such territory forming behavior that monopolize unnecessarily abundant amount of food resource by one individual is not still understood well. To get insights to the evolutionary orgin of the territory formation by Ayu, we model behavior of each individual of Ayu by individual based model. Based on the computers simulation, we discuss the origin of the territory formation by Ayu fish., 2001年05月10日, 2001, 37, 15, 18

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書籍等出版物

• Chapter "Evolution and Maintenance of Egg Rejection by Hosts as Adaptation Against Conspecific Brood Parasites: An Individual-Based Model" in Avian Brood Parasitism, Behaviour, Ecology, Evolution and Coevolution, Springer International Publishing, 高須夫悟, 分担, 2018年04月, 英語, 査読無し, その他
• 招かれない虫たちの話 虫がもたらす健康被害と害虫管理, 第11章「感染症流行の数理的研究」執筆, 東海大学出版部, 高須夫悟, 分担, 2017年03月, 日本語, 査読無し, その他, 9784486021254
• 行動生物学辞典, 東京化学同人, 高須夫悟, 分担, 2013年11月, 日本語, 査読無し, その他
• シリーズ現代の生態学・第5巻・行動生態学 第5章執筆, 共立出版, 高須夫悟, 分担, 2012年06月, 98- 119, 日本語, 査読無し, その他, 9784320057388
• 数理科学事典, 丸善, 高須夫悟, 筆頭著者, 2009年11月, 278-281, 日本語, 査読無し, その他
• 個体性を保ったダイナミクスモデル シリーズ 数理生物学要論 巻2「空間」の数理生物学 第6章, 共立出版, 高須夫悟, 筆頭著者, 2009年05月, 第6章, 日本語, 査読無し, その他
• オナガの分布域拡大に伴うカッコウとの新たな関係、「鳥の自然史」第6章, 北海道大学出版会, 高須夫悟, 分担, 2009年, 第6章, 日本語, 査読無し, その他
• 進化 分子・個体・生態系, メディカル・サイエンス・インターナショナ, 高須夫悟, 分担, 2009年, 第20章, 日本語, 査読無し, その他
• 持続不可能性 - 環境保全のための複雑系理論入門（共訳）\nFragile Dominion by Simon Levin (1999) Perseus Publishing, Cambridge, Massachusetts, 持続不可能性 - 環境保全のための複雑系理論入門 文一総合出版, 高須夫悟, 2003年10月, 1-376頁, 日本語, 査読無し, その他
• リンデンマイヤー・システムとしての植物根系の形態（共著）, 生物の形の多様性と進化 － 遺伝子から生態系まで －\n関村利朗・野地澄晴・森田利仁 共編 裳華房 第14章, 高須夫悟, 2003年06月, 152-162頁, 日本語, 査読無し, その他
• 数理生態学と鳥類学－托卵を題材にして－ 第8章執筆（191-222）, これからの鳥類学\n山岸哲・樋口広芳 共編 裳華房, 高須夫悟, 2002年, 第8章(191-222項), 日本語, 査読無し, その他
• 新人口論－生態学的アプローチ\nHow many people can the earth support? Joel. E. Cohen\n共訳, 新人口論－生態学的アプローチ\n農山漁村文化協会, 656 pages, 高須夫悟, 1998年, 日本語, 査読無し, その他

講演・口頭発表等

• TAKASU Fugo, 国際, The 8th CIJK Conference on Mathematical and Theoretical Biology, Spatial population dynamics as point process, シンポジウム・ワークショップパネル（公募）, 2023年06月27日, 2023年07月01日, 英語
• TAKASU Fugo, 国際, The 10th EAFES International Congress, Measuring the degree of egg mimicry in avian brood parasitism - a point pattern approach to quantify egg appearance, シンポジウム・ワークショップパネル（公募）, 2023年07月17日, 2023年07月20日, 英語
• 高須夫悟, 国内, 統計思考院人材育成事業ワークショップ 数学を用いる生物学：理念・概念と実践・方法論, Spatial population dynamics as point process, 公開講演，セミナー，チュートリアル，講習，講義等, 2023年08月28日, 2023年08月29日, 日本語
• TAKASU Fugo, 国内, The Fifth Workshop on Interdisciplinary Sciences (WIS 2023) Graduate School of Bioresource and Bioenvironmental Sciences, Kyushu University, The method of moments - how individual-based rules of birth, death, and movements of individuals are translated to a dynamical system in spatial ecology, シンポジウム・ワークショップパネル（指名）, 2023年09月13日, 2023年09月14日, 英語
• 高須夫悟, 国内, 個体群生態学会シンポジウム「COVID-19の個体群生態学：疫学と個体群管理の共通点と相違点, マツ枯れ対策と空間個体群動態モデル, シンポジウム・ワークショップパネル（指名）, 2022年10月01日, 2022年10月01日, 日本語
• 高須夫悟, 国内, 数学を用いる生物学：理念・概念と実践・方法論, 個体の視点に基づく点パターンダイナミクスの導出の仕方, 口頭発表（一般）, 2022年07月20日, 2022年07月21日, 日本語
• TAKASU Fugo, 国際, Annual meeting of the Society for Mathematical Biology 2021, Estimation of spatial interaction kernel from time series data - a point pattern approach, シンポジウム・ワークショップパネル（公募）, 2021年06月13日, 2021年06月17日, 英語
• TAKASU Fugo, 国際, International Workshop, From behavior to biodiversity linking with population invasion and establishment, Daejeon, Korea, Population invasion models as a point process, シンポジウム・ワークショップパネル（公募）, 2021年11月25日, 2021年11月26日, 英語
• 高須夫悟, 国内, 日本生態学会第69回大会, 力学系モデルから個体ベースモデルを作るやり方, シンポジウム・ワークショップパネル（公募）, 2022年03月14日, 2022年03月19日, 日本語
• TAKASU Fugo, 国際, 中国・西安工程大学セミナー, Equilibrium properties of the spatial SIS model as a point pattern dynamics, 公開講演，セミナー，チュートリアル，講習，講義等, 2019年12月05日, 2019年12月05日, 英語
• TAKASU Fugo, 国際, 中国・西安交通大学セミナー, Mathematical and computational approaches to spatial modeling in ecology 1-2, 公開講演，セミナー，チュートリアル，講習，講義等, 2019年12月03日, 2019年12月04日, 英語
• TAKASU Fugo, 国際, M4WARM Conference at Thuyloi University, Hanoi, Vietnam, Assessment of egg patter mimicry using local image descriptors, シンポジウム・ワークショップパネル（指名）, 2019年11月17日, 2019年11月18日, 英語
• TAKASU Fugo, 国際, ニュージーランド・オークランド大学生物科学科セミナー, Spatial metapopulation dynamics as a point pattern dynamics, 公開講演，セミナー，チュートリアル，講習，講義等, 2019年11月12日, 2019年11月12日
• 高須夫悟, 国内, 日本数理生物学会2019年大会, Spatial metapopulation dynamics as a point pattern dynamics, 2019年09月16日, 日本語
• 高須夫悟, 国際, Seminar at the department of mathematics, Dhaka University, Bangladesh, Equilibrium properties of the spatial SIS model as a point pattern dynamics, 2019年02月, 英語, 国際会議
• 高須夫悟; Fugo TAKASU, 国際, Mathematical modeling workshop at EnFRA, Equilibrium properties of the spatial SIS model as a point pattern dynamics, 2018年12月, 英語, EnFRA in Busan, Korea, 国際会議
• 高須夫悟, 国際, Mini-workshop on the new development of aquatic ecosystem model, An approach to study adaptive community dynamics, 2018年12月, 英語, Hanyang University ERICA, Korea, 国際会議
• 高須夫悟, 国際, Seminar at the department of biology, Kyung Hee University, Korea, Equilibrium properties of the spatial SIS model as a point pattern dynamics, 2018年12月, 英語, Kyung Hee University, Seoul, Korea, 国際会議
• 高須夫悟, 国際, Seminar at the department of physics, Inha University, Korea, Equilibrium properties of the spatial SIS model as a point pattern dynamics, 2018年12月, 英語, Inha University, Incheon, Korea, 国際会議
• 高須夫悟, 国際, The 8th EAFES (East Asian Federation of Ecological Societies) International Congress, Spatial metapopulation dynamics as a point pattern dynamics, 2018年04月, 英語, East Asian Federation of Ecological Societies, Nagoya University, Nagoya, Japan, 国際会議
• 濱田実樹; 高須夫悟, 日本生態学会第65回大会, Spatial metapopulation dynamics as a point pattern dynamics, 2018年03月, 日本語, 日本生態学会, 札幌コンベンションセンター、札幌市, 国内会議
• 高須夫悟, Seminar at the School of Mathematics and Statistics of Wuhan University, Spatial population dynamics of biological phenomena, 2017年12月, 英語, School of Mathematics and Statistics of Wuhan University, Wuhan, China, 国際会議
• 高須夫悟, Seminar at the School of Mathematical Sciences of Soochow University, Mathematical and Computational Approaches to Spatial Modeling in Ecology, 2017年12月, 英語, School of Mathematical Sciences of Soochow University, Suzhou, China, 国際会議
• 高須夫悟, ISEM 2017 Global Conference Pre-conference short course, Mathematical and computational approaches to spatial modelling in ecology, 2017年09月, 英語, Society of Ecological Modeling, Jeju island, Korea, 国際会議
• 高須夫悟, ISEM 2017 Global Conference, Jeju, Korea, Modeling the spatial spread spread of the pine wilt disease - how does vector beetle dispersal affect disease expansion?, 2017年09月, 英語, Society of Ecological Modeling, Jeju island, Korea, 国際会議
• 高須夫悟, Seminar at National Institute of Ecology of Korea, Meta-population dynamics as a stochastic point pattern, 2017年09月, 英語, National Institute of Ecology of Korea, Gunsan, Korea, 国際会議
• 高須夫悟, VNU NUS Miniworkshop "Selected topics in mathematical modeling", Point pattern dynamics - a challenge to work on spatial population dynamics, 2016年11月, 英語, VNU University of Science, Hanoi, Vietnam, 国際会議
• 高須夫悟, Symposium - What is a good model? Evidential statistics, information criterion and model evaluation, Spatial population dynamics as a point pattern dynamics, 2016年01月, 英語, 統計数理研究所, 国際会議
• 高須夫悟, Seminar at the Institute of Forestry and Environmental Science, Chittagong University, Bangladesh, Hidden Markov Model as a tool to study animal behaviors, 2015年11月, 英語, Chittagong University, Bangladesh, 国際会議
• 高須夫悟, 東京大学大学院数理科学研究科・数理生物学セミナー, Spatial population dynamics as a point pattern dynamics, 2015年11月, 日本語, 東京大学駒場キャンパス, 国内会議
• 高須夫悟, Symposium "Advances in spatial ecology", JSMB CJK 20015, Doshisha University 26- 29 August 2015., Spatial epidemic models as a point pattern dynamics, 2015年08月, 英語, Japan Society for Mathematical Biology, Joint meeting with China, Japan, and Korea 2015, 同志社大学今出川キャンパス, 国際会議
• 高須夫悟, Seminar talk at the Chinese Academy of Forestry, Beijing, Modeling the spatial spread of the pine wilt disease - an individual-based approach, 2015年01月, 英語, Beijing, China, 国際会議
• 高須夫悟, Seminar talk at the Institute of Zoology, Chinese Academy of Sciences, Beijing, Modeling the maintenance of egg polymorphism over geographic scale, 2015年01月, 英語, Beijing, China, 国際会議
• 高須夫悟, Seminar at Kyung Hee University, Seoul, Korea, Modeling the spatial spread of the pine wilt disease - an individual-based approach, 2014年12月, 英語, Seoul, Korea, 国際会議
• 高須夫悟, Seminar at the Institute of Forestry and Environmental Science of the University of Chittagong, Chittagong, Bangladesh, Modeling spatial spread of infectious disease - an individual-based approach, 2014年11月, 英語, Chittagong, Bangladesh, 国際会議
• 高須夫悟, Seminar at Busan National University, Busan, Korea, Modeling the spatial spread of the pine wilt disease - an individual-based approach, 2014年11月, 英語, Busan, Korea, 国際会議
• 高須夫悟, IUFRO 2014, International Union of Forest Research Organizations, Modeling the spatial spread of the pine wilt disease - an individual-based approach, 2014年10月, 英語, Salt Lake City, Utah, USA, 国際会議
• 高須夫悟, The Joint annual meeting of the Japanese society for mathematical biology and the society for mathematical biology, A spatial modeling of egg mimicry in avian brood parasitism, 2014年08月, 英語, Japanese society for mathematical biology and the society for mathematical biology, 大阪グランキューブ, 国際会議
• 高須夫悟, The 26th International Ornithological Congress, Modeling the maintenance of egg polymorphism over geographic scale, 2014年08月, 英語, Rikkyo University, Tokyo, 国際会議
• 高須夫悟, Seminar talk at Jeju National University, Jeju, Korea, Modeling spatial dynamics of egg polymorphism in a cuckoo-host interactions, 2014年06月, 英語, Jeju, Korea, 国際会議
• 高須夫悟, Seminar talks at Busan National University, Busan, Korea, 1) Spatial population dynamics of "games for territory", 2) Modeling spatial spread of infectious disease - an individual-based approach, 3) Modeling spatial dynamics of egg polymorphism in a cuckoo-host interactions, 2014年06月, 英語, Busan, Korea, 国際会議
• 高須夫悟, College of Life Sciences, Hainan Normal University, China, Individual-based modeling of the spread of the pine wilt disease, 2013年12月, 英語, 国際会議
• 高須夫悟, Institute of Forestry and Environmental Sciences, University of Chittagong, Bangladesh, 1) A spatial territory game in continuous space\n2) Individual-based modeling of the spread of pine wilt disease, 2013年05月, 英語, Chittagong, 国際会議
• 高須夫悟, 日本生態学会第60回全国大会\n企画集会T05「個体の視点から構成する空間個体群動態」, 連続空間上の個体ベース個体群動態, 2013年03月, 日本語, 日本生態学会, 静岡県コンベンションセンター（グランシップ）, 国内会議
• 高須夫悟, International Symposium on Avian Brood Parasitism in Honour of Significant Brood Parasitism Scientists, Modeling maintenance of egg polymorphism over a geographical scale, 2012年11月, 英語, Hainan Normal University, Norwegian University of Science and Technology, and China Ornithological Society, Haikou, Hainan province, China, 国際会議
• 高須夫悟, 第13回ライチョウ会議岐阜大会, 日本のライチョウ集団のの絶滅可能性解析, 2012年10月, 日本語, 高山市役所ホール, 国内会議
• 高須夫悟, The 12th International Grouse Symposium, An individual-based stochastic population dynamics of the Rock Ptarmigan in Japan, 2012年07月, 英語, Matsumoto, Nagano, Japan, 国際会議
• 高須夫悟, China-Japan-Korea International Conference of Mathematical Biology, Individual-based models of spatial population/evolutionary dynamics, 2012年05月, 英語, Korean Society of Mathematical Biology, Busan, Korea, 国際会議
• 高須夫悟, 日本鳥学会員近畿地区懇談会第103回例会, 鳥類育児寄生における卵色多型の集団遺伝モデル, 2011年12月, 日本語, 奈良女子大学, 国内会議
• 高須夫悟, 個体群生態学会 第27回大会（岡山大学 10月14- 16日） 企画シンポジウム「個体ベースで考える集団の争い」, 個体の視点から組み立てる個体群動態モデル, 2011年10月, 日本語, 岡山大学, 国内会議
• 高須夫悟, 第21回日本数理生物学会（明治大学 9月13- 15日）企画シンポジウム「空間的制約下におけるダイナミクス」, 連続空間上の個体ベース個体群動態とその数理的取り扱いについて, 2011年09月, 日本語, 明治大学, 国内会議
• 高須夫悟, 日本生態学会第69回大会, 力学系モデルから個体ベースモデルを作るやり方, 2022年03月18日, その他
• TAKASU Fugo, International Workshop, From behavior to biodiversity linking with population invasion and establishment, Daejeon, Korea, Population invasion models as a point process, 2021年11月25日, 英語
• TAKASU Fugo, Annual meeting of the Society for Mathematical Biology 2021, Estimation of spatial interaction kernel from time series data - a point pattern approach, 2021年06月16日, 英語
• 高須夫悟; 太田花藍, 個体群生態学会シンポジウム「COVID-19の個体群生態学：疫学と個体群管理の共通点と相違点」, マツ枯れ対策と空間個体群動態モデル, 2022年10月01日, 日本語
• 高須夫悟, 数学を用いる生物学：理念・概念と実践・方法論, 個体の視点に基づく点パターンダイナミクスの導出の仕方, 2022年07月21日, 2022年07月20日, 2022年07月21日, 日本語
• TAKASU Fugo, The Fifth Workshop on Interdisciplinary Sciences (WIS 2023) Graduate School of Bioresource and Bioenvironmental Sciences, Kyushu University, The method of moments - how individual-based rules of birth, death, and movements of individuals are translated to a dynamical system in spatial ecology, 2023年09月14日, 2023年09月14日, 2023年09月15日, 英語

  共同研究・競争的資金等URL
• 高須 夫悟, 統計思考院人材育成事業ワークショップ 数学を用いる生物学：理念・概念と実践・方法論＠統計数理研究所, Spatial population dynamics as point process, 2023年08月29日, 2023年08月28日, 2023年08月29日, 日本語

  共同研究・競争的資金等URL
• TAKASU Fugo, The 10th EAFES International Congress, Measuring the degree of egg mimicry in avian brood parasitism - a point pattern approach to quantify egg appearance, 2023年07月18日, 2023年07月17日, 2023年07月20日, 英語

  共同研究・競争的資金等URL
• TAKASU Fugo, The 8th CIJK Conference on Mathematical and Theoretical Biology, Spatial population dynamics as point process, 2023年06月28日, 2023年06月27日, 2023年07月01日, 英語

  共同研究・競争的資金等URL

Works（作品等）

• Evolutionary games in continuous space, 2008年
• Evolutionary games in continuous space, 2008年
• Evolution of competition, 2005年03月, 2005年12月
• Evolution of competition, 2005年03月, 2005年12月
• Brood parasitism in arctic area, 2005年11月
• Brood parasitism in arctic area, 2005年11月
• Avian brood parasitism, 2005年09月
• Avian brood parasitism, 2005年09月
• Coevolution of avian brood parasites and their hosts, 2003年06月, 2005年05月
• Coevolution of avian brood parasites and their hosts, 2003年06月, 2005年05月
• Evolution of host defense in avian brood parasitism, 2002年01月
• Evolution of host defense in avian brood parasitism, 2002年01月

受賞

• The Akira Okubo Prize, The Society for Mathematical Biology and the Japanese Society for Mathematical Biology, 2007年07月
• Ecological Research 論文賞（2007年度）, 日本生態学会, 2007年03月

共同研究・競争的資金等の研究課題

• 基盤研究C, 2022年, 2024年, 22K06401, 研究代表者, 点パターンの視点に基づく空間生態学理論の新たな展開
• 基盤研究 (C), 2022年04月01日, 2025年03月31日, 22K06401, 研究代表者, 点パターンの視点に基づく空間生態学理論の新たな展開
• 2010年, 空間個体群動態ならびに空間進化動態, 科学研究費補助金, 0, 0, 0, 競争的資金
• 2010年, Spatial population and evolutionary dynamics, Grant-in-Aid for Scientific Research, 0, 0, 0, 競争的資金
• 進化動態に関する数理的研究, 0, 0, 0, 競争的資金
• 動物の分散に関する理論的研究, 0, 0, 0, 競争的資金
• 鳥類の育児寄生における共進化の理論的研究, 0, 0, 0, 競争的資金
• Evolurionary dynamics, 0, 0, 0, 競争的資金
• Theoretical Study on animal dispersal, 0, 0, 0, 競争的資金
• Theoretical study on avian brood parasitism, 0, 0, 0, 競争的資金
• 基盤研究(C), 2022年04月, 2025年03月, 22K06401, 研究代表者, 点パターンの視点に基づく空間生態学理論の新たな展開, 高須 夫悟, 日本学術振興会, 科学研究費助成事業 基盤研究(C), 奈良女子大学, 3120000, 2400000, 720000, kaken;rm:published_papers;rm:presentations;rm:presentations;rm:presentations

  対象リソースIRI
• 基盤研究(B), 2006年, 2009年, 18405009, オーストラリア熱帯に生息する小型カッコウ類と宿主の進化的軍拡競争に関する行動生態学的研究, 上田 恵介; 江口 和洋; 西海 功; 高木 昌興; 高須 夫悟; 濱尾 章二; 濱尾 章二, 日本学術振興会, 科学研究費助成事業, 立教大学, 13190000, 11000000, 2190000, オーストラリア・ダーウィンにおいてアカメテリカッコウとその2種の宿主の調査を実施した。その結果、寄生者のヒナを宿主のハシブトセンニョムシクイとマングローブセンニョムシクイが積極的に排除するという事実が世界ではじめて明らかになった。ヒナ排除の事実はこれまでの托卵鳥研究で報告されたことはない。アカメテリカッコウはもともとハシブトセンニョムシクイを主要宿主として、ヒナ擬態を進化させたものであろうが、近年、マングローブセンニョムシクイにも寄生をはじめたものと考えられる。, kaken

  対象リソースIRI
• 基盤研究(B), 2002年, 2005年, 14340243, 宿主に対応したカッコウの系統は雌側の遺伝子により進化するか, 中村 浩志; 林田 信明; 田口 悟朗; 高須 夫悟, 日本学術振興会, 科学研究費助成事業, 信州大学, 13300000, 13300000, 長野市郊外千曲川での20年間にわたるカッコウの研究から、カッコウ卵の模様等の形質は、雌側の遺伝子のみによって伝えられることで、それぞれの宿主卵に似た卵を産むカッコウの系統(gentes)が進化した可能性が高いことが明らかにされた。今回のプロジェクト研究は、この点について、個体識別された母と娘について卵の模様の比較、遺伝子解析、托卵行動の観察によりさらに実証することで、カッコウと宿主の攻防戦を通し、カッコウ卵の模様の進化が起こる仕組みを解明することを目的に、平成14年度から17年度まで研究を実施したので以下に調査結果の概要等について報告する。 (1)ミトコンドリアDNA解析結果 長野県内の千曲川、野辺山高原、乗鞍高原を調査地に、さまざまな宿主の巣探しを行い、托卵されたカッコウ卵の発見に務め、無事に育った計86雛から血液サンプルを採集でき、ミトコンドリアDNAを分析した。その結果、日本では地域と宿主の違いによる変異が大きく、イギリスのカッコウで見出されたような宿主に対応した系統関係は、日本ではあいまいであるという結論となった。そのため、卵擬態や托卵系統は雌側を通して進化するという結論は正しいとしても、両地域では卵模様や系統の進化に違いがあることが明らかとなった。 (2)カッコウの雛への足輪による標識調査結果 野辺山高原で計78羽の雛に足輪をつけて放鳥することができた。しかし、同じ調査地に翌年以降も戻り、再捕獲することができた個体はいなかった。そのため、雛の時から標識した個体に発信機を装着し、行動を追跡することにより、自分を育てたと同じ宿主に托卵するかどうかを確認することはできなかった。 (3)娘とその母親の卵模様について 雛の時から標識した個体を再捕獲し、発信機を装着した追跡調査を行うことができなかったため、今回の野辺山高原の調査では、これまでの千曲川での調査結果である娘の卵は母親の卵に似ているという結果に、新たな資料を加えることができなかった。 (4)外国の研究者との情報交換と共同研究、および成果の公表 ケンブリッジ大学のN.B.Davies教授およびハンガリーのDr.Csaba Moskatらカッコウ研究者を2004年と2005年に訪れ、情報交換と調査結果の検討、今後の調査内容の検討を行うことができた。また、スペインのカッコウ研究者A.Roman Munozと野辺山高原で2004年と2005年に共同研究を実施することができた。さらに、平成16年には、ハンガリー、ケンブリッジ大学、ノルウエー大学のカッコウ研究者を招聘し、2005年9月に奈良女子大学での日本鳥学会大会の折に「托卵鳥と宿主の相互進化」のシンポジウムを開催し、日本での研究成果の一部を公表することができた。また、今回のプロジェクト研究の成果の一部は、日本鳥学会大会で口頭発表すると共に、論文として2編を日本鳥学会誌に発表することができた。未発表の成果については、今後論文等に発表してゆく予定である。, kaken

  対象リソースIRI
• 若手研究(B), 2002年, 2004年, 14740421, 群集動態に関する新しい理論アプローチの展開, 高須 夫悟, 日本学術振興会, 科学研究費助成事業, 奈良女子大学, 3400000, 3400000, 平成16年度は主に以下の2点に注目した研究を行った。 1)寄生系におけるパラサイトのハンドリングタイムの進化モデル解析 ホスト・パラサイトの個体群動態において、パラサイトが寄生を実行するに要する時間(ハンドリングタイム)が小さくなると安定平衡点が不安定化し周期解・カオスが出現する事は既に古典モデルの解析に明らかになっている。本研究ではパラサイト集団中にハンドリングタイムに関する集団内変異が存在すると仮定した場合、ハンドリングタイムの進化が個体群動態の安定性に及ぼす影響について解析した。前年度に行った、パラサイトの探索効率の進化モデルと同様、ハンドリングタイムは小さくなる方向へ進化するが、パラサイトのハンドリングタイムに関する集団内変異の存在は、個体群動態をより長期にわたって安定することを見いだした。また、探索効率やハンドリングタイムといった個体群動態に関係するパラメータの進化と個体群動態の安定性に関する一般的な研究を行った。 2)解析的モデルと個体ベースシミュレーションモデルの比較 群集動態や個体群動態の理論研究で用いられる数理モデルの多くは解析的な取り扱いが易い決定論的解析的モデル(差分式、微分方程式等)を用いて記述される。しかし、現実の系では確率論的な効果が無視できず決定論的モデルで起こりうる微小密度下での振る舞いは、必ずしも現実の系を反映していないと思われる。本研究では、決定論的解析モデルで設定される様々な仮定を確率論的ルールに置き換えた確率論的個体ベースモデルを構築し、両者の振る舞いを比べる事で、決定論的解析モデルでは捉えられない現象がある事を見いだした。具体的には、適応度の谷間をすり抜けて形質の進化が起こりうる等である。同様の解析を寄生系の個体群動態モデル及び群集動態モデルに対して行い、確率的な効果の重要性を再認識した。現在はこれを発展させたモデル解析を進めている。, kaken

  対象リソースIRI
• 基盤研究(C), 2001年, 2003年, 13640627, 侵入生物の飛び火的分散と時・空間伝播パターンに関する数理的研究, 重定 南奈子; 高須 夫悟; 川崎 廣吉, 日本学術振興会, 科学研究費助成事業, 奈良女子大学, 2900000, 2900000, 一般に、飛び火は極めて稀な事象であることから確率的なプロセスとして捉えなければならない.特に,一分散個体が定着に成功するかどうかは,人口学的確率性やアリー効果の存在により大きく左右される.さらに,分散個体の出現速度はローカルな個体群動態によって規定される.これらの側面を適切に組み入れた侵入生物の分布拡大に関するモデルとして,セルオートマトンモデルならびに差分積分モデルの確率論バーションを構築した. ついで,モデルの数学的解析を行うことにより,飛び火的分散が分布パターンの時・空間パターンにどのような影響を与えるかを明らかにし,特に,拡がる速度を飛び火の頻度と飛び火の平均移動距離の関数として表す一般公式を導出した. さらに,上記モデルの応用例として,茨城県で拡がったマツ枯れの感染伝播過程をシミュレートした.即ち,マツ枯れの主因である材センチュウを媒介するマツノマダラカミキリのローカル分散ならびに長距離分散の確率密度分布を導入した.また,分布域の時空間変化は茨城県の平均的なマツ林のブロックをセルの単位としたセルオートマトンの上で評価した.これにより,茨城県全域におけるマツの初期分布や被害の年次変化等の膨大なデータを効率的に組み込んで、マツガレの伝播パターンを再現することに成功した.その結果、茨城県での4km/年にも及ぶ高い伝播速度は、全カミキリ中の10%に満たない長距離分散個体が引き起こしていることが明らかになった.さらに、マツガレ防除が分布拡大速度をどの程度減少させうるかについても詳細な検討を行った。, kaken

  対象リソースIRI
• 奨励研究(A), 2000年, 2001年, 12740422, 量的形質に関する共進化の数理的解析, 高須 夫悟, 日本学術振興会, 科学研究費助成事業, 奈良女子大学, 2100000, 2100000, 平成13年度は、昨年度に実施した量的形質に関する共進化モデルの解析をさらに推し進めた。理論解析を進めると同時に、野外での寄生者宿主の関係(カッコウとその宿主)に関するデータを収集し、モデル解析結果と実際の系との比較検討を現在進めている。以下に今年度の研究成果の要点をまとめる。 1)積分差分方程式で記述される本研究のモデルは、遺伝変異が集団内に十分存在すると仮定した場合、従来の量的遺伝モデルとの接点を持つ。しかし、数学的な関連性は未だ不明な点が多く、今後の理論的研究が必要である。また、本研究では卵模様のように量的形質が親から子へそのまま受け継がれる場合を解析したが、有性生殖に一般的な交配による量的形質の変化の効果をモデルに組み込むアイデアをモデル解析の過程で得ることが出来た。現在、その数理的取り扱いについて研究中である。 2)進化一般を議論する新しい理論的枠組みとして、理想自由進化モデルを提唱した。従来の多くのESSモデルの様に集団を一様な「点」として取り扱うのではなく、変異を持った「分布」として取り扱うことで、より柔軟な理論解析が可能になる。 3)托卵鳥系における寄生者と宿主の卵模様(量的形質)の変化を実証することを目指して、2001年6月に琵琶湖にてカッコウの宿主であるオオヨシキリの卵の写真を撮影し、卵模様の画像データを入手した。現在画像データの定量的解析を進めており、共進化の実証を試みている。 4)2年間の研究の取りまとめとして、2001年7月に開催された、数理生物国際会議にて研究発表を行い、内外の研究者と議論を交わした。本研究成果は論文として国際誌に投稿し、査読中である(2001年11月Evolution誌に投稿済み)。 5)寄生系以外の系でも、量的形質を巡る共進化が積分方程式を用いた基本的に同じ枠組みで理論的に取り扱い可能であることを明らかにした。 平成12・13年の2年間で量的形質の共進化に関する理論的研究を大きく推進することが出来た。同時に、今後取り組むべき新たな課題も浮かび上がってきた。この2年間の研究補助をきっかけに、更なる理論的解析を推進していきたい。, kaken

  対象リソースIRI
• 基盤研究(C), 1998年, 2000年, 10640616, マツガレの侵入と空間的伝播に関する数理的研究, 重定 南奈子; 高須 夫悟; 川崎 廣吉, 日本学術振興会, 科学研究費助成事業, 奈良女子大学, 2400000, 2400000, マツ枯れの流行はマツ,カミキリ,ザイセンチュウの三者の種間相互作用によって,その推移が大きく規定されている.これら3者の間の直接・間接相互作用を取り入れた個体群動態モデルを構築し,マツ枯れの初期侵入,定着,そして空間的な広がりがどのように進展していくか数理的解析をおこなった. (1)マツ枯れの病原体であるザイセンチュウの移動は媒介者であるカミキリの移動を通してのみ行われるため,カミキリの移動分散行動についての生態学的特性はマツガレの空間的伝播過程を決定づける極めて重要な要素である.そこで,カミキリの空間的移動を考慮に入れた数理モデルを構築した.カミキリは羽化するとすぐに移動を開始するが,そのときの移動距離のデータがFujioka(1993),Shibata(1981),Togashi(1989)によって報告されており,それらを総合して移動距離に関する密度分布関数を求めた.これには,通常のカミキリが行うランダム拡散的な近距離分散と人為的に或いは風に乗ってに飛び火的に移動する長距離分散が含まれる.つぎに,両分散を自然な形で組み入れるために,移動距離分布を積分核にした積分微分方程式の枠組みでモデル化を行った. (2)このモデルを茨城県で1971年に突発したマツ枯損の伝搬過程(岸1995)に適用し,伝播過程の詳細なシミュレーションを行った.具体的には,マツ枯れ侵入前のマツ林の分布を2次元の地図上に記録し,この上でマツ枯れがどのように広がるかを実際に起こった分布拡大と対比させながら解析した.その結果,カミキリの短距離移動個体だけでは年間数百メートルしか拡がらないのに対して,長距離移動個体が全体の1割程度存在すれば茨城県で見られた年間4kmの拡大速度が理論的に説明できることが明らかになった., kaken

  対象リソースIRI
• 基盤研究(C), 1996年, 1997年, 08640804, 侵入生物の分散と地理的伝播過程に関する数理的研究, 重定 南奈子; 高須 夫悟; 川崎 廣吉, 日本学術振興会, 科学研究費助成事業, 奈良女子大学, 2500000, 2500000, 1.マツノマダラカミキリの個体群ダイナミクスとマツ枯れ伝播に関する数理的研究-マツ枯れの流行は基本的にはマツとマツノザイセンチュウとマツノマダラカミキリの三者の相互作用を介して行われるので、流行の推移は三者の個体群動態により規定されているといえる.富樫(1989)によって行われた石川県の砂丘地におけるクロマツ林で起こったマツ枯れを1980-1983年間の調査データをもとに,マツ・マツノマダラカミキリおよびマツノザイセンチュウの相互作用を取り入れた数理モデルをつくり,これを解析することにより,マツ枯れの流行の長期変動の予測を行った.また,マツノマダラカミキリの駆除によりマツ枯れの伝播がどのように制御されるかを考察し,以下の結果をえた. (1).マツ枯れが流行するためにはマツの初期密度にある閾値があり,この閾値密度よりも小さいマツ密度では,いかなる初期カミキリ密度においても流行は起こらない.また,この閾値密度はカミキリの駆除率の上昇に伴って増加する. (2).流行が終焉するまでにどれだけのマツが感染するかを駆除率の関数として求めた.駆除率が1に近いと残存マツ密度は初期マツ密度に近いが,駆除率が小さくなると初期マツ密度が大きいほど,一マツ当たりの感染割合が急速に高くなる. 2.環境が人為的に分断化されている状況の中を生物が侵入したとき,それが定着して存続する条件,分布域を広げることのできる条件,ならびに,その空間的な伝播速度を求めた.とくに,環境が道路などにより帯状に分断された場合と格子状に分断された場合の2つを取り上げ,数学的解析とコンピュータシミュレーションを行うことにより,伝播速度に関する解析的な公式を導くことに成功した., kaken

  対象リソースIRI
• 奨励研究(A), 1996年, 1996年, 08740600, Generalist托卵鳥系における宿主の行動進化の理論的研究, 高須 夫悟, 日本学術振興会, 科学研究費助成事業, 奈良女子大学, 1000000, 1000000, 托卵鳥とその宿主の関係における進化生態学的な問題について数理モデルを用いた研究を行った。托卵されたあるホスト集団は、托卵鳥(パラサイト)の卵を認識して排除する托卵対抗手段をとることが野外研究によって明らかなっているが、托卵対抗手段の確立度はホスト集団ごとに異なっており、この事実に対する明確な説明はなされていなかった。本研究は、托卵鳥が同時に複数の種類のホスト集団に托卵する系(Generalist系)について、托卵対抗手段がそれぞれのホスト集団中でどのように確立されるのかについての数理モデルを組み立て、モデル解析を通じて現実に対する新たな視点を見出すことを目的とした。本研究により明らかになった点は以下の通りである。 1.托卵鳥コウウチョウに托卵されるホストは、托卵対抗手段を殆ど行わないAccepter speciesと、ほぼ完璧な托卵対抗手段をみせるRejecter speciesに分類されることが野外研究から明らかにされているが、このような極端な2分化は、コウウチョウの繁殖戦略-Generalistによって引き起こされている可能性が高い。 2.托卵されながらも托卵対抗手段を行わないAccepter speciesは、対抗手段が突然変異として出現すればRejecter speciesになるという説(Evolutionary Lag説)がある。これに対し、モデル解析から、Accepter speciesの存在は進化的に安定であり、2局化した托卵対抗手段の確立度分布は安定である可能性(Evolutionary Equilibrium説)が示された。この場合、Accepter speciesとRejecter speicesの間には、集団サイズの大きさなどの測定可能な量に違いがあり、これを測定することによって2つの説のどちらがより適切であるかが検討可能である。, kaken

  対象リソースIRI
• 基盤研究(C), 2014年04月01日, 2017年03月31日, 26440239, 点パターンの定量化に注目した空間生態学の新たな数理的展開, 高須 夫悟, 日本学術振興会, 科学研究費助成事業, 奈良女子大学, 4940000, 3800000, 1140000, 空間生態学における空間個体群動態を点パターンダイナミクスとして定式化する研究に取り組んだ。点パターンの1次構造（点密度）と2次構造（2点からなるペア距離分布）に注目し、1次と2次構造に関する力学系モデルを導出した。具体的には、点パターンダイナミクスを確率過程として再現するシミュレーションと、1次・2次構造に関する力学系の比較である。力学系モデルには3次構造（3点からなるトリプレット）が含まれるが、これを低次構造で近似する方法（モーメントクロージャー）に取り組んだ。点の出生と死亡が無い場合においては、簡単なモーメントクロージャーで非常に精度よくシミュレーションを記述できることを明らかにした。, kaken;rm:presentations

  対象リソースIRI
• 基盤研究(A), 2011年04月01日, 2015年03月31日, 23255004, 南半球における托卵性鳥類と宿主の軍拡競争の新展開：温帯ドグマからの脱却, 上田 恵介; 江口 和洋; 西海 功; 高須 夫悟; 高木 昌興; 三上 修, 日本学術振興会, 科学研究費助成事業, 立教大学, 44200000, 34000000, 10200000, 2014年度までの４年間で，ニューカレドニアにおけるカッコウの調査はかなり大きな進展があった。野外調査はニューカレドニアにおける共同研究者、ポーランド科学アカデミーのTheuerkauf博士と共同で行った。主な成果は第26回国際鳥類学会議（東京2014）国際行動生態学会議（2014ニューヨーク）、日本鳥学会大会、日本動物行動学会大会で発表した．また国際誌へ３本の論文を発表した。社会への貢献活動として、横浜市立動物園と共催で、期間中に市民向けのシンポジウム（カグーシンポ，飛べない鳥シンポ）を２回開催した。, kaken

  対象リソースIRI
• 基盤研究(C), 2011年, 2013年, 23570026, 個体の視点に基づく進化ゲーム理論の新たな展開, 高須 夫悟, 日本学術振興会, 科学研究費助成事業, 奈良女子大学, 5330000, 4100000, 1230000, 利得表に基づく古典的進化ゲーム理論を個体の視点から再構築する研究に取り組んだ。具体的には、タカハトゲーム、囚人のジレンマゲーム、協力の進化ゲームといったモデルを連続空間上の個体ベースモデルとして構成し、個体レベルの機械論的相互作用から集団レベルの振る舞いをシミュレーションする枠組みを完成させ解析した。個体の空間配置を点パターンとして捉え、点の数とペアの数のダイナミクスとして捉えることで、シミュレーション結果を説明する力学系の導出に取り組んだ。従来離散的な格子空間上で議論されてきた空間進化ゲームの振る舞いが連続空間上の空間進化ゲームとは大きく異なることを示し、両者の接点について理解を深めた。, kaken

  対象リソースIRI

Ⅲ．社会連携活動実績

１．公的団体の委員等（審議会、国家試験委員、他大学評価委員，科研費審査委員等）

• 2002年, 2003年, 学協会
• 日本生態学会, 近畿地区会事務局幹事, 2002年, 2003年, 学協会
• 学協会
• 日本数理生物学会, 運営委員, 学協会
• 学協会
• 日本鳥学会, 英文誌編集委員、広報委員, 学協会
• 2012年01月, 9999年, 学協会
• 2005年01月, 9999年, 学協会