| title: | Sex-specific variance of body size in insects: patterns and causes |
|---|---|
| reg no: | ETF4998 |
| project type: | Estonian Science Foundation research grant |
| subject: |
1.15. Zoology |
| status: | completed |
| institution: | Institute of Zoology and Botany at Estonian University of Life Sciences |
| head of project: | Tiit Teder |
| duration: | 01.01.2002 - 31.12.2004 |
| description: | In insects, phenotypic variance in adult body size tends to be higher in females than in males. Surprisingly, however, there appear to be no reviews devoted to this subject, neither is the applicant aware of any attempts to provide an explanation - proximate or evolutionary - to this remarkable pattern. The absence of an analysis of the phenomenon is unfortunate, however, because the case seems to have a potential to contribute to solving various general problems in evolutionary biology. The question if there may be sex-specific differences in the 'potential' for developmental canalisation in body size is open, and of particular interest in the present context. The aim of the present project is to compare and analyse patterns of body size variation of males and females in various insects. We intend to integrate some basic concepts of trait variation (canalisation, accumulation of variation, bet-hedging, constraints) to explain sex-specific patterns of variance. As the starting point of this project, we are planning to survey available literature for studies that have reported variances in adult body size for males and females separately. The review will answer the question of how general is the pattern of sex-specific differences in body size variance in insects, and if there is any dependence on taxon, life-history strategies, sexual size dimorphism etc. Several specific hypotheses will be tested. One of the features that may substantially affect sex-specific variance patterns in body size is the degree to which adult feeding is displayed in a particular species. Another feature of insects, potentially important with regard to body size variation, is larval feeding phenology. Phylogenesis-based methods will be used in the analyses. Patterns of body size variation in the respective groups will be discussed in the light of basic concepts of evolution of trait variation. To elucidate sources of sex-specific variance in body size, one objective of this study is to investigate which factors determine variance in adult size of males and females on the proximate level. It will be asked if females are more sensitive to random environmental factors ('noise') during their larval development either due to, or irrespective of the difference in the number of larval instars. The project would provide a generalized overview of sex-specific patterns of body size variation in insects. The results would broaden understanding of mechanisms that determine actual variation of body size in insects. The outcome of this project is planned to consist of four articles being published in leading international journals in the field of ecology. |
| project group | ||||
|---|---|---|---|---|
| no | name | institution | position | |
| 1. | Tiit Teder | Institute of Zoology and Botany, EAU | Researcher | |