Climate and ecology predict latitudinal trends in sexual selection inferred from avian mating systems
File(s)
Published version
Author(s)
Type
Journal Article
Abstract
Sexual selection, one of the central pillars of evolutionary theory, has powerful effects on organismal morphology, behaviour, and population dynamics. However, current knowledge about geographical variation in this evolutionary mechanism and its underlying drivers remains highly incomplete, in part because standardised data on the strength of sexual selection is sparse even for well-studied organisms. Here, we use information on mating systems—including the incidence of polygamy and extra-pair paternity—to estimate the intensity of sexual selection in 10,671 (>99.9%) bird species distributed worldwide. We show that avian sexual selection varies latitudinally, peaking at higher latitudes, although the gradient is reversed in the world’s most sexually selected birds—specialist frugivores—which are strongly associated with tropical forests. Phylogenetic models further reveal that the strength of sexual selection is explained by temperature seasonality coupled with a suite of climate-associated factors, including migration, diet, and territoriality. Overall, these analyses suggest that climatic conditions leading to short, intense breeding seasons, or highly abundant and patchy food resources, increase the potential for polygamy in birds, driving latitudinal gradients in sexual selection. Our findings help to resolve longstanding debates about spatial variation in evolutionary mechanisms linked to reproductive biology and also provide a comprehensive species-level data set for further studies of selection and phenotypic evolution in the context of global climatic change.
Editor(s)
Quental, Tiago Bosisio
Date Issued
2024-11-01
Date Acceptance
2024-09-20
Citation
PLoS Biology, 2024, 22 (11)
ISSN
1544-9173
Publisher
Public Library of Science (PLoS)
Journal / Book Title
PLoS Biology
Volume
22
Issue
11
Copyright Statement
© 2024 Barber et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
License URL
Identifier
https://www.ncbi.nlm.nih.gov/pubmed/39495808
PII: PBIOLOGY-D-23-03406
Subjects
Biochemistry & Molecular Biology
Biology
BIRDS
BREEDING SYNCHRONY
DIMORPHISM
DIVERSITY
EVOLUTION
EXTRA-PAIR PATERNITY
Life Sciences & Biomedicine
Life Sciences & Biomedicine - Other Topics
LIFE-HISTORY
MIGRATION
OPPORTUNITY
Science & Technology
SPERM COMPETITION
Publication Status
Published
Coverage Spatial
United States
Article Number
e3002856
Date Publish Online
2024-11-04