| Autor: |
Ferreira MS; Programa de Pós-graduação em Ecologia, Departamento de Ecologia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil.; Laboratório de Vertebrados, Departamento de Ecologia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil.; Applied Ecology and Conservation Lab, Departamento de Ciências Biológicas, Universidade Estadual de Santa Cruz, Bahia, Brazil., Dickman CR; School of Life and Environmental Sciences, University of Sydney, Sydney, New South Wales, Australia., Fisher DO; School of Biological Sciences, University of Queensland, Queensland, Australia., Figueiredo MSL; Programa de Pós-Graduação em Biodiversidade Neotropical, Instituto de Biociências, Universidade Federal do Estado do Rio de Janeiro, Rio de Janeiro, Brazil., Vieira MV; Programa de Pós-graduação em Ecologia, Departamento de Ecologia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil.; Laboratório de Vertebrados, Departamento de Ecologia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil. |
| Abstrakt: |
Previous studies have suggested that mammal life history varies along the fast-slow continuum and that, in eutherians, this continuum is linked to variation in the potential contribution of survival and reproduction to population growth rate ( λ ). Fast eutherians mature early, have large litters and short lifespans, and exhibit high potential contribution of age at first reproduction and fertility to λ , while slow eutherians show high potential contribution of survival to λ . However, marsupials have typically been overlooked in comparative tests of mammalian life-history evolution. Here, we tested whether the eutherian life-history pattern extends to marsupials, and show that marsupial life-history trade-offs are organized along two major axes: (i) the reproductive output and dispersion axis, and (ii) the fast-slow continuum, with an additional association between adult survival and body mass. Life-history traits that potentially drive changes in λ are similar in eutherians and marsupials with slow life histories, but differ in fast marsupials; age at first reproduction is the most important trait contributing to λ and fertility contributes little. Marsupials have slower life histories than eutherians, and differences between these clades may derive from their contrasting reproductive modes; marsupials have slower development, growth and metabolism than eutherians of equivalent size. |
