Evolutionary patterns in life-history traits of lizards of the genus Xenosaurus
Por:
Jaime Zuniga-Vega, J., Fuentes-G, Jesualdo A., Gaston Zamora-Abrego, J., Garcia-Vazquez, Uri O., Nieto-Montes de Oca, Adrian, Martins, Emilia P.
Publicada:
1 oct 2017
Resumen:
Life histories are directly related to fitness and, hence, are the focus of strong selective pressures. However, different life-history traits may evolve at different paces and may respond differentially to particular selective pressures. We examined patterns of evolutionary change in the following life-history traits of xenosaurid lizards: size at maturity, average size of adult females, litter size, neonate size, and relative litter mass. We used a phylogenetic hypothesis of the genus Xenosaurus and different phylogenetic comparative methods to search for evolutionary relationships between traits as well as to estimate ancestral states, rates of evolution, and the amount of phylogenetic signal on each trait. In addition, we searched for differences in these life-history traits among the different environments where these lizards inhabit (cloud forest, tropical forest, oak-pine forest, and xeric scrub). We found an evolutionary relationship between size at maturity and average adult size, with larger species maturing at larger sizes. We also found an evolutionary trade-off between litter size and neonate size. Ancestral state reconstructions revealed differences among traits in the relative timing of diversification. Litter size and neonate size began diversification early in the history of the genus. In contrast, size at maturity and relative litter mass remained phenotypically invariant for a long time period before diverging into distinct phenotypic values. Litter size exhibited significant phylogenetic signal because the diversification history of this trait has tracked the phylogeny closely. The observed variation among species in neonate size also showed some trace of the phylogenetic relationships. The remaining three traits diverged throughout time without a clear phylogenetic pattern. In addition, litter size and relative litter mass exhibited the highest evolutionary rates whereas average adult size and neonate size exhibited the lowest rates. Litter size was the only trait that differed significantly among environments, with largest litters in cloud forests. We discuss potential hypotheses to explain the observed differences among life-history traits in the tempo and mode of evolution. © 2017, British Herpetological Society. All rights reserved.
Filiaciones:
Jaime Zuniga-Vega, J.:
Univ Nacl Autonoma Mexico, Fac Ciencias, Dept Ecol & Recursos Nat, Ciudad Univ, Mexico City 04510, DF, Mexico
Fuentes-G, Jesualdo A.:
Indiana Univ, Dept Bot, Bloomington, IN 47405 USA
Gaston Zamora-Abrego, J.:
Univ Nacl Colombia, Fac Ciencias Agr, Dept Ciencias Forestales, Medellin 050034, Antioquia, Colombia
Garcia-Vazquez, Uri O.:
Univ Nacl Autonoma Mexico, Fac Estudios Super Zaragoza, Batalla 5 Mayo S-N, Iztapalapa 09230, DF, Mexico
Nieto-Montes de Oca, Adrian:
Univ Nacl Autonoma Mexico, Fac Ciencias, Dept Biol Evolut, Lab Herpetol, Ciudad Univ, Mexico City 04510, DF, Mexico
Martins, Emilia P.:
Indiana Univ, Dept Bot, Bloomington, IN 47405 USA
Arizona State Univ, Sch Life Sci, Tempe, AZ 85287 USA
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