Lifespan decreases with proportion of sons in males but not females of zoo-housed tigers and lemurs.

摘要: Several studies have shown higher costs of rearing sons than daughters in mammals where males are larger females. These typically focus on females by examining how the offspring sex ratio during a single reproductive event affected mothers' subsequent reproduction or survival probability. Here, we examine relationships between multiple events and several metrics mothers fathers, using data from zoo-housed tigers (Panthera tigris) ruffed lemurs (Varecia sp.). Our analyses failed to reveal an overall cost mothers. In male lemurs, proportion produced early life (before 10 years old) was negatively correlated with lifespan later life. tigers, their lifetime had shorter lifespans. One likely mechanism is difference testosterone levels males: high concentration can increase compromise immune function. results suggest wild populations should address outstanding challenge understanding consequences allocation for males, open opportunity predict applied conservation context.