Sexual size monomorphism may evolve in lizards with a body size maximizing reproductive performance for both sexes  

作　　者：Hong-Liang Lu Jian-Fang Gao Kun Guo Xiang Ji 

机构地区：[1]Hangzhou Key Laboratory for Ecosystem Protection and Restoration,School of Life and Environmental Sciences,Hangzhou Normal University,Hangzhou 311121,Zhejiang,China [2]Zhejiang Provincial Key Laboratory for Water Environment and Marine Biological Resources Protection,College of Life and Environmental Sciences,Wenzhou University,Wenzhou 325035,Zhejiang,China

出　　处：《Current Zoology》2023年第3期277-283,共7页动物学报（英文版）

基　　金：This work was carried out in compliance with the current laws of China and was supported by grants from the National Natural Science Foundation of China(32071511,31301878,and 31300339)。

摘　　要：We used Takydromus septentrionalis,a sexually size-monomorphic lacertid lizard,as a model system to test the hypothesis that sexual size monomorphism may evolve in lizards where reproductive performance is maximized at a similar body size for both sexes.We allowed lizards housed in laboratory enclosures to lay as many clutches(for females)as they could or to mate as many times(for males)as they could in a breeding season.Size-assortative mating was weak but evident in T.septentrionalis,as revealed by the fact that male and female snout–vent lengths(SVLs)in mating pairs were significantly and positively correlated.Mating frequency(indicative of male reproductive performance)varied from 1 to 8 per breeding season,generally increasing as SVL increased in adult males smaller than 67.4 mm SVL.Clutch frequency varied from 1 to 7 per breeding season,with female reproductive performance(determined by clutch frequency,annual fecundity,and annual reproductive output)maximized in females with a SVL of 68.0 mm.Accordingly to our hypothesis,the reproductive performance was maximized in the intermediate sized rather than the largest individuals in both sexes,and the body size maximizing reproductive performance was similar for both sexes.Future work could usefully investigate other lineages of lizards with sexually monomorphic species in a phylogenetic context to corroborate the hypothesis of this study.

关 键 词：annual fecundity annual reproductive output clutch frequency mating frequency Takydromus septentrionalis 

分 类 号：Q95[生物学—动物学]