TY  - JOUR
AB  - Adult sex ratio (ASR) is a central concept in population biology and a key factor in sexual selection, but why do most demographic models ignore sex biases? Vital rates often vary between the sexes and across life history, but their relative contributions to ASR variation remain poorly understood—an essential step to evaluate sex ratio theories in the wild and inform conservation. Here, we combine structured two-sex population models with individual-based mark–recapture data from an intensively monitored polygamous population of snowy plovers. We show that a strongly male-biased ASR (0.63) is primarily driven by sex-specific survival of juveniles rather than adults or dependent offspring. This finding provides empirical support for theories of unbiased sex allocation when sex differences in survival arise after the period of parental investment. Importantly, a conventional model ignoring sex biases significantly overestimated population viability. We suggest that sex-specific population models are essential to understand the population dynamics of sexual organisms: reproduction and population growth are most sensitive to perturbations in survival of the limiting sex. Overall, our study suggests that sex-biased early survival may contribute toward mating system evolution and population persistence, with implications for both sexual selection theory and biodiversity conservation.
DA  - 2017
DO  - 10.1073/pnas.1620043114
KW  - ASR
KW  - Charadrius nivosus
KW  - mark-recapture
KW  - sex allocation
KW  - two-sex matrix model
LA  - eng
IS  - 27
M2  - E5474
PY  - 2017
SN  - 0027-8424
SP  - E5474-E5481
T2  - Proceedings of the National Academy of Sciences of the United States of America
TI  - Sex-specific early survival drives adult sex ratio bias in snowy plovers and impacts mating system and population growth
UR  - https://nbn-resolving.org/urn:nbn:de:0070-pub-29132690
Y2  - 2024-11-25T03:09:04
ER  -