Abstract
In species with marked sexual dimorphism and where one sex undergoes stronger intrasexual competition, that sex is expected to age earlier or quicker. Here, we utilise a unique, longitudinal dataset of a semi-captive population of Asian elephants (Elephas maximus), a species with marked male-biased intrasexual competition, with males being larger and living shorter, and test the hypothesis that males show earlier and/or faster body mass ageing than females. We show sex-specific ageing trajectories: adult males gained weight up to the age of 48 years old, followed by a decrease in body mass until natural death. In contrast, adult females gained body mass with age until a body mass decline in the last year of life. Our study shows that sex-specific life-histories shape ageing patterns consistent with the predictions of the classical theory of ageing.
Competing Interest Statement
The authors have declared no competing interest.
Footnotes
Discussion updated: We now explicitly state that the absence of terminal decline in males body mass is possibly due to a limited sample size, and we removed sentences suggesting that the absence of males terminal decline in body mass reflects sex-specific body mass trajectory at the end of life