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Title: Proximate determinants of family size in an obligate egg-feeding frog
The number of offspring parents rear varies considerably among closely related lineages, individuals, and even reproductive events by one individual. Constraints can come at any point, from the costs of producing a large clutch to the cost of caring for a large brood of dependent young. We report here on observations of the early phase of a reproductive cycle in a captive colony of Oophaga pumilio, a poison frog with offspring entirely dependent on maternally provisioned trophic eggs. We tracked reproductive clutches, and found that while clutch and egg size were variable, neither predicted the success of a clutch; there was also no evidence of a trade-off between clutch and egg size. Larger eggs did, however, produce larger tadpoles, and when parents transported only a subset of the brood to nurseries, the tadpoles they moved were larger than the ones they did not. Adaptive adjustment of parental investment is a key life-history trait, and a complete accounting of the way families are constructed is key to understanding the evolution of parental care, parental favoritism, and cooperation and conflict among closely related individuals.  more » « less
Award ID(s):
1742224
PAR ID:
10464267
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
Evolutionary Ecology
ISSN:
0269-7653
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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