Just a matter of size?Evaluating allometry and intersexual heterometry in Pagurus bernhardus using ratios and indices(Decapoda,Anomura)  

作　　者：Michel SCHMIDT Ines MARTIN Roland R.MELZER 

机构地区：[1]Bavarian State Collection of Zoology,Bavarian Natural History Collections,Munich,Germany [2]Faculty of Biology,Biocenter,Ludwig-Maximilians-Universität München,Planegg-Martinsried,Munich,Germany [3]Ocean Museum Germany,Stralsund,Germany [4]GeoBio-Center,Ludwig-Maximilians-Universität München,Munich,Germany

出　　处：《Integrative Zoology》2024年第5期807-823,共17页整合动物学(英文版)

基　　金：financial support from the Deutsche Forschungsgemeinschaft,Award Number Me-2683/10-1(to M.S.).

摘　　要：Heterochely denotes the presence of dissimilarly sized chelipeds on opposite sides of the body,a prevalent occurrence in diverse crustaceans.Conversely,heterometry pertains to the quantifiable disparities in size between these chelipeds.Both chelipeds hold pivotal roles in activities such as foraging,mating,and defense.Consequently,individuals of both genders in heterochelic species exhibit this morphological pattern.Previous studies have identified sexual dimorphism in cheliped size,with males displaying larger major chelipeds compared to females,albeit solely relying on propodus length as a size proxy and focusing solely on the major cheliped.In our study,we meticulously examined 190 specimens of the common European hermit crab Pagurus bernhardus from two collections.We sought to elucidate allometric relationships and assess whether heterometry exhibited sex-based differences when adjusting for body size by using ratios.Our findings revealed that male chelipeds displayed hyperallometric growth relative to females,and all three calculated heterometry indices exhibited significant disparities between the sexes.Consequently,male specimens exhibited larger major and minor chelipeds,even when theoretically matched for body size with females.This phenomenon may be attributed,among other factors,to male-male contests.Should indirect mate selection favor males with larger chelipeds in proportion to their body size,this dynamic could potentiate sexual selection in their favor.

关 键 词：allometric growth body-size correction chelipeds hermit crabs heterochely natural selection sexual selection 

分 类 号：F42[经济管理—产业经济]