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Mammals with Small Populations Do Not Exhibit Larger Genomes
Adam B Roddy1, David Alvarez-Ponce2, Scott W Roy3
1Institute of Environment, Department of Biological Sciences, Florida International University, Miami, FL, USA.
Molecular Biology and Evolution
|May 6, 2021
Summary
Large genome size in mammals is not linked to small population size, challenging the Drift-Barrier Hypothesis. This study found no correlation, suggesting other factors influence genome evolution.
Area of Science:
- Evolutionary Biology
- Genomics
- Population Genetics
Background:
- Genome size varies greatly across cellular organisms, but the underlying causes are not fully understood.
- The Drift-Barrier Hypothesis posits that small populations favor large genomes due to relaxed selection.
Purpose of the Study:
- To conduct the first explicit test of the Drift-Barrier Hypothesis.
- To investigate the relationship between population size and genome size in mammals.
Main Methods:
- Compared census population size and genome size across 199 mammal species.
- Accounted for potential covariates and phylogenetic history.
Main Results:
- No significant correlation was found between census population size and genome size in mammals.
- The study provides empirical evidence against a direct link proposed by the Drift-Barrier Hypothesis.
Conclusions:
- Population size does not appear to be the primary driver of genome size variation in mammals.
- The Drift-Barrier Hypothesis requires further investigation and may need revision.
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