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Related Experiment Video

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Following the Dynamics of Structural Variants in Experimentally Evolved Populations

Following the Dynamics of Structural Variants in Experimentally Evolved Populations

Published on: February 3, 2023

The one-third law of evolutionary dynamics.

Hisashi Ohtsuki¹, Pedro Bordalo, Martin A Nowak

¹Program for Evolutionary Dynamics, Harvard University, Cambridge, MA 02138, USA. ohtsuki@fas.harvard.edu

Journal of Theoretical Biology

|September 11, 2007

Summary

This summary is machine-generated.

A new study explains the "one-third law" in evolutionary game dynamics. It reveals that strategy A fixates in a B-population due to individuals interacting more with B than A players, explaining the 1/3 frequency.

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Area of Science:

Evolutionary biology
Game theory
Population dynamics

Background:

Frequency-dependent fitness is crucial for trait selection in finite populations.
The "one-third law" of evolutionary dynamics describes strategy fixation but lacks a clear origin.
Existing models like the Moran process and graph games support this law.

Purpose of the Study:

To provide an intuitive explanation for the origin of the "one-third law" in evolutionary game dynamics.
To elucidate the underlying stochastic processes governing strategy fixation.
To connect the one-third law to average Malthusian fitness.

Main Methods:

Analysis of stochastic processes in evolutionary game dynamics.
Investigating individual interactions within finite populations.
Mathematical derivation of the relationship between interaction frequency and fixation probability.

Main Results:

An intuitive explanation for the "one-third law" is established.
Individuals interact, on average, twice as often with B-players as with A-players during an invasion attempt.
This interaction bias directly yields the one-third fixation law.

Conclusions:

The study clarifies the stochastic basis of the "one-third law" in evolutionary dynamics.
The findings provide a mechanistic understanding of trait selection with frequency-dependent fitness.
The one-third law implies a positive average Malthusian fitness for the invading strategy.