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INBREEDING AND VARIANCE EFFECTIVE POPULATION NUMBERS.

James F Crow1, Carter Denniston1

  • 1Genetics Department, University of Wisconsin, Madison, WI, 53706.

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|June 1, 2017
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Summary
This summary is machine-generated.

This study derives formulas for the inbreeding effective number (NeI) and variance effective number (NeV) in populations. These calculations are crucial for understanding genetic diversity and population structure in various species.

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Area of Science:

  • Population genetics
  • Quantitative genetics
  • Evolutionary biology

Background:

  • Effective population size is a key metric in population genetics.
  • Previous models for effective population size have limitations in certain scenarios.
  • Understanding inbreeding and variance effective numbers is vital for conservation and evolutionary studies.

Purpose of the Study:

  • To derive and present corrected and extended expressions for the inbreeding effective number (NeI) and variance effective number (NeV).
  • To provide formulas applicable to various population models, including those with self-fertilization and distinguished sexes.
  • To offer a more comprehensive framework for calculating effective population size in diverse biological systems.

Main Methods:

  • Mathematical derivation of formulas for NeI and NeV.
  • Consideration of diploidy, random mating, and discrete generations.
  • Analysis of six specific situations for NeI (isogamous, monoecious with/without self-fertilization, separate sexes) and two for NeV (monoecious, separate-sexed).

Main Results:

  • Formulas for NeI are provided for isogamous, monoecious, and separate-sexed populations, with and without self-fertilization.
  • Formulas for NeV are derived for monoecious and separate-sexed populations.
  • The study presents specific equations incorporating covariance and variance of progeny numbers and grandparental generation size.

Conclusions:

  • The derived expressions offer a more robust and detailed estimation of effective population size.
  • These formulas are applicable to a wider range of organisms, particularly those with separate sexes.
  • The work provides essential tools for analyzing genetic drift, inbreeding, and effective population size in evolutionary and conservation genetics.