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Does Body Shape in Fundulus Adapt to Variation in Habitat Salinity?
Joseph M Styga1,2, Jason Pienaar1, Peter A Scott1,3
1Department of Biological Sciences, The University of Alabama, Tuscaloosa, AL, United States.
Frontiers in Physiology
|December 6, 2019
Summary
Habitat salinity influences fish body shape evolution, impacting physiology and fitness. Fundulus fish show body shape changes linked to osmoregulatory needs across different salinities and life stages.
Area of Science:
- Evolutionary biology
- Ichthyology
- Ecology
Background:
- Body shape is crucial for fish physiology and fitness.
- Fundulus fish display significant variation and habitat transitions (freshwater to saltwater).
- Understanding ecological pressures on body shape is key.
Purpose of the Study:
- To investigate if habitat salinity influences the macroevolution of Fundulus body shape.
- To examine these effects across different developmental stages (ontogeny).
Main Methods:
- Phylogenetic comparative analysis accounting for phylogenetic inertia.
- Examination of body shape variation in Fundulus across various salinity environments.
- Analysis across multiple ontogenetic stages.
Main Results:
- Body shape deviates from optimal streamlining due to salinity.
- Deviations are consistent with osmoregulatory pressures at all examined ontogenetic stages.
- Saline-intolerant species have lower surface area shapes; inland, salt-tolerant species resemble marine species.
Conclusions:
- Habitat salinity is a significant driver of Fundulus body shape evolution.
- Selection for osmoregulatory efficiency shapes body morphology.
- Body shape adaptations are evident throughout ontogeny in response to salinity.
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