Ecological factor that drives evolution of body color variation in orb-web spiders

2017 Fiscal Year Final Research Report

• Project/Area Number: 26440251
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Ecology/Environment
• Research Institution: Kyoto Women's University
• Principal Investigator: Nakata Kensuke 京都女子大学, 現代社会学部, 教授 (80331031)
• Co-Investigator(Kenkyū-buntansha): 繁宮 悠介 長崎総合科学大学, 総合情報学部, 准教授 (00399213)
• Project Period (FY): 2014-04-01 – 2018-03-31
• Keywords: 体色 / 種内変異 / 造網 / 種間比較 / 円網 / クモ / 配偶頻度 / シミュレーション

Outline of Final Research Achievements

Trade-off between different selection pressure is a hypothesis to explain individual variation in animal body color. This study examined the possibility that, while trade-off pattern changes periodically, shorter generation time of the animal would help the evolution and the maintenance of body color variation. We examined the ecology of four species of orb-web spider genus Cyclosa which have monomorphic species and species with small and large body color variation. Results showed that the negative relationship between generation time and the magnitude of body color variation. We also examined the relationship between body color and foraging efficiency or web site selection, the lifetime mating number, and built a population dynamics model that incorporated these results and assumed that the body color was heritable trait. The results of simulation supported our hypothesis, i.e., shorter generation time increased the extent of body color variation.

Free Research Field

動物生態学