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Sexual dimorphism in a trophically polymorphic cichlid fish?
Christopher Darrin Hulsey1, Francisco J García-De León2, Axel Meyer1
1Department of Biology, University of Konstanz, Konstanz, 78457, Germany.
Journal of Morphology
|August 21, 2015
Summary
Sexual dimorphism does not drive trophic diversity in Herichthys minckleyi. While body size varied by sex, other trophic traits and pharyngeal jaw morphology did not show this association.
Area of Science:
- Evolutionary Biology
- Ecology
- Ichthyology
Background:
- Sexual dimorphism is common in animal traits, but trophic polymorphism is less frequent.
- Understanding the link between sex and phenotypic divergence can explain species' morphological variability.
- Herichthys minckleyi exhibits intraspecific trophic polymorphism, making it a model for this study.
Purpose of the Study:
- To investigate the association between sex and morphological divergence in Herichthys minckleyi.
- To determine if sexual dimorphism contributes to maintaining ecomorphological variation in this cichlid species.
Main Methods:
- Examined the relationship between sex and various morphological traits in Herichthys minckleyi.
- Assessed pharyngeal morphotype, body size (standard length), gut length, gape, and tooth number.
- Analyzed the association between sex and pharyngeal morphotype, and between morphotype and other trophic traits.
Main Results:
- No association was found between sex and pharyngeal morphotype in Herichthys minckleyi.
- Sex was associated with divergence in body size (standard length).
- Pharyngeal morphotype showed associations with gut length, gape, and tooth number, but not sex.
Conclusions:
- Sexual dimorphism is not a primary driver of trophic diversity in Herichthys minckleyi.
- Ecomorphological variation in this species is influenced by factors other than sexual dimorphism in trophic traits.
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