DISENTANGLING THE CONTRIBUTION OF SEXUAL SELECTION AND ECOLOGY TO THE EVOLUTION OF SIZE DIMORPHISM IN PINNIPEDS

@article{Krger2014DISENTANGLINGTC,
  title={DISENTANGLING THE CONTRIBUTION OF SEXUAL SELECTION AND ECOLOGY TO THE EVOLUTION OF SIZE DIMORPHISM IN PINNIPEDS},
  author={Oliver Kr{\"u}ger and Jochen B. W. Wolf and Rudy M. Jonker and Joseph Ivan Hoffman and Fritz Trillmich},
  journal={Evolution},
  year={2014},
  volume={68}
}
The positive relationship between sexual size dimorphism (SSD) and harem size across pinnipeds is often cited as a textbook example of sexual selection. It assumes that female aggregation selected for large male size via male–male competition. Yet, it is also conceivable that SSD evolved prior to polygyny due to ecological forces. We analyzed 11 life‐history traits in 35 pinniped species to determine their coevolutionary dynamics and infer their most likely evolutionary trajectories contrasting… Expand

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References

SHOWING 1-10 OF 66 REFERENCES
THE ORIGINS OF SEXUAL DIMORPHISM IN BODY SIZE IN UNGULATES
TLDR
A phylogeny of extant ungulate species, along with maximum‐likelihood statistical techniques, are used to provide a test of Jarman's hypothesis, which states that sexual size dimorphism evolved in a three‐step process. Expand
The Evolution of Reversed Sexual Size Dimorphism in Hawks, Falcons and Owls: A Comparative Study
TLDR
The results suggest that RSD in hawks, falcons and owls evolved due to natural-selection pressures rather than sexual-selection pressure, consistent with the small-male hypothesis. Expand
Phylogenetic analyses of primate size evolution: the consequences of sexual selection
TLDR
An independent contrast analysis of male and female size (log weight) showed that these are tightly correlated and that size dimorphism is not a simple allometric function of size, and the directional investigation indicates that the magnitude of change in haplorhine dimorphisms is larger after an increase in sexual selection than after a decrease. Expand
Comparative analyses of the influence of developmental mode on phenotypic diversification rates in shorebirds
TLDR
It is found that precocial development not only allows rapid divergence of parental care and mating behaviours, but also promotes the rapid diversification of secondary sexual characters, most notably sexual size dimorphism (SSD) in body mass. Expand
The evolution of sexual dimorphism in parasitic cuckoos: sexual selection or coevolution?
TLDR
It is shown that size and plumage differences between the sexes in parasitic cuckoos are more likely the result of coevolution than sexual selection, and the evolution of brood parasitism was associated with more cryptic plumage in both sexes, but especially in females, a result that contrasts with the strong plumage dimorphism seen in some other parasitic birds. Expand
Variance in male reproductive success and sexual size dimorphism in pinnipeds: testing an assumption of sexual selection theory
TLDR
The theory of evolution by sexual selection for sexual size dimorphism postulates that SSD primarily reflects the adaptation of males and females to their different reproductive roles, and species with male-biased SSD are predicted to have greater variance in male reproductive success than those in which both sexes are similar in size. Expand
Ecological Causes for the Evolution of Sexual Dimorphism: A Review of the Evidence
  • R. Shine
  • Biology, Medicine
  • The Quarterly Review of Biology
  • 1989
TLDR
If ecological causation for dimorphism can be demonstrated in so many cases, despite the inadequacies of the available criteria, the degree of sexual sizeDimorphism in many other animal species may well also have been influenced by ecological factors, and it may be premature of dismiss this hypothesis. Expand
SEXUAL SIZE DIMORPHISM IN SHOREBIRDS, GULLS, AND ALCIDS: THE INFLUENCE OF SEXUAL AND NATURAL SELECTION
Charadrii (shorebirds, gulls, and alcids) have an unusual diversity in their sexual size dimorphism, ranging from monomorphism to either male-biased or female-biased dimorphism. We use comparativeExpand
Phylogenetic analyses of sexual selection and sexual size dimorphism in pinnipeds
TLDR
The hypothesis that sexual size dimorphism in pinnipeds is the product of an exclusively male response to sexual selection is supported. Expand
Allometry for Sexual Size Dimorphism: Pattern and Process in the Coevolution of Body Size in Males and Females
Sexual size dimorphism (SSD) is common in both plants and animals, and current evidence suggests that it reflects the adaptation of males and females to their different reproductive roles. WhenExpand
...
1
2
3
4
5
...