Extensive Population Structure Highlights an Apparent Paradox of Stasis in the Impala (Aepyceros melampus)
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View abstract on PubMed
Summary
This summary is machine-generated.Impalas exhibit evolutionary stasis, but whole-genome sequencing reveals low genetic diversity and significant population structure. Natural selection appears less efficient in eastern African impalas, suggesting a fixed-optimum model for their long-term stability.
Area Of Science
- Evolutionary biology
- Genomics
- Conservation genetics
Background
- Impalas (Aepyceros melampus) are noted for their remarkable evolutionary stasis, maintaining morphological similarity over millions of years.
- Understanding the genetic underpinnings of this stasis is crucial for impala conservation and evolutionary studies.
Purpose Of The Study
- To investigate the evolutionary forces driving impala evolutionary stasis.
- To explore genetic diversity and population structure within and between impala subspecies.
Main Methods
- Whole-genome sequencing of 119 impala individuals from two subspecies.
- Phylogeographic analysis to infer population expansion and gene flow.
- Analysis of runs of homozygosity and genetic load to assess natural selection efficiency.
Main Results
- Low overall genetic diversity was observed across impala populations.
- Pronounced genetic structure exists between and within common and black-faced impala subspecies, with evidence of ancient gene flow.
- Eastern African impala populations showed higher homozygosity and reduced efficiency of natural selection compared to southern African populations.
Conclusions
- Results support a fixed-optimum model of evolutionary stasis, where southern African impalas maintain fitness optima.
- Eastern African impalas may face challenges adapting to local environments due to genetic drift and reduced selection efficiency, potentially leading to recurrent local extinctions and recolonization events.
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