Detection of reduction in population size using data from microsatellite loci

Area of Science:

• Population genetics
• Conservation genetics
• Molecular ecology

Background:

• Microsatellite loci are powerful tools for studying population genetics.
• Detecting past population size changes is crucial for effective conservation management.
• Existing methods may not accurately distinguish between recent and prolonged population bottlenecks.

Purpose of the Study:

• To introduce and validate a new metric, M, for detecting historical reductions in population size using microsatellite data.
• To develop a statistical test based on M for identifying recent population size declines.
• To assess the utility of M in predicting demographic histories of real-world populations.

Main Methods:

• Simulations were conducted using various mutation models to evaluate the behavior of M under different population size scenarios.
• The M statistic was calculated for diverse populations using existing microsatellite data from scientific literature.
• A statistical test was developed to detect recent population size reductions based on M values.

Main Results:

• The M statistic (mean ratio of alleles to allele size range) decreases with population size reductions.
• The magnitude of M decrease correlates with the severity and duration of population bottlenecks.
• M can differentiate between recently and historically small populations, with recovery rates linked to post-reduction size.

Conclusions:

• The M statistic is a reliable indicator of past population size changes, particularly recent reductions.
• The developed statistical test can detect population size reductions for over 100 generations.
• The M metric shows significant promise for population management and conservation strategies.