The life histories of orders of mammals: Fast and slow breeding [Les histoires de vie des ordres de mammifères : reproduction rapide et lente].

Résumé

Mammalian species are known to follow a pattern of efastf life histories in species with small body sizes and eslowf life histories in species with large body sizes. We studied components or axes of life-history variation among ten orders of mammals. Five life-history traits that are sufficient to describe population growth were used: age at maturity, length of reproductive lifespan, juvenile survival, adult survival and mean fertility. Results showed that an axis based on principal components analyses of life histories was significantly and strongly associated with body mass. We show that rabbits and hares have significantly faster life histories, and bats and primates have significantly slower life histories than expected for their body size. Bovidae and Sciuridae, very different sized herbivore families, have similar (close to average score) life histories along the fast–slow continuum. Within sciurids, tree squirrels appeared to have faster life histories than ground squirrels. These results independently confirmed previous conclusions about life histories among mammalian orders.