Traits that reflect the amount of energy allocated to offspring by mothers, such as infant body mass, are predicted to have long‐lasting effects on offspring fitness. In very long‐lived species, such as anthropoid primates, where long‐lasting and obligate parental care is required for successful recruitment of offspring, there are few studies on the fitness implications of low body mass among infants. Using body mass data collected from 253 free‐ranging rhesus macaque Rhesus macaque infants experienced on average 5% reduced hazard of death for an increase in body mass of 0.1 Infant body mass tended to be lower if mothers were young or old, but the link between infant body mass and early life survival remained after controlling for maternal age. This finding suggests that maternal effects on early life survival such as maternal age may act through their influence on infant body mass. Mothers of heavier infants were less likely to be delayed in subsequent reproduction, but the estimated association slightly overlapped with zero. The timing of the last week of suckling did not differ by infant body mass. Using infant body mass data that has been rarely available from free‐ranging primates, our study provides comparative evidence to strengthen the existing body of literature on the fitness implications of variation in infant body mass.
- PAR ID:
- 10309928
- Date Published:
- Journal Name:
- Proceedings of the National Academy of Sciences
- Volume:
- 118
- Issue:
- 1
- ISSN:
- 0027-8424
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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A free
Plain Language Summary can be found within the Supporting Information of this article. -
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1073/pnas.2015317118
