A stochastic field theory for the evolution of quantitative traits in finite populations

Fuente: arXiv
Saved in:
Bibliographic Details
Main Author: Bhat, Ananda Shikhara
Format: Preprint
Published: 2024
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866913823305236480
author Bhat, Ananda Shikhara
author_facet Bhat, Ananda Shikhara
contents Infinitely many distinct trait values may arise in populations bearing quantitative traits, and modeling their population dynamics is thus a formidable task. While classical models assume fixed or infinite population size, models in which the total population size fluctuates due to demographic noise in births and deaths can behave qualitatively differently from constant or infinite population models due to density-dependent dynamics. In this paper, I present a stochastic field theory for the eco-evolutionary dynamics of finite populations bearing one-dimensional quantitative traits. I derive stochastic field equations that describe the evolution of population densities, trait frequencies, and the mean value of any trait in the population. These equations recover well-known results such as the replicator-mutator equation, Price equation, and gradient dynamics in the infinite population limit. For finite populations, the equations describe the intricate interplay between natural selection, noise-induced selection, eco-evolutionary feedback, and neutral genetic drift in determining evolutionary trajectories. My work uses ideas from statistical physics, calculus of variations, and SPDEs, providing alternative methods that complement the measure-theoretic martingale approach that is more common in the literature.
format Preprint
id arxiv_https___arxiv_org_abs_2406_10739
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle A stochastic field theory for the evolution of quantitative traits in finite populations
Bhat, Ananda Shikhara
Populations and Evolution
Statistical Mechanics
Probability
Biological Physics
92D15 (Primary) 92D25, 60H15, 60J68, 60J70 (Secondary)
Infinitely many distinct trait values may arise in populations bearing quantitative traits, and modeling their population dynamics is thus a formidable task. While classical models assume fixed or infinite population size, models in which the total population size fluctuates due to demographic noise in births and deaths can behave qualitatively differently from constant or infinite population models due to density-dependent dynamics. In this paper, I present a stochastic field theory for the eco-evolutionary dynamics of finite populations bearing one-dimensional quantitative traits. I derive stochastic field equations that describe the evolution of population densities, trait frequencies, and the mean value of any trait in the population. These equations recover well-known results such as the replicator-mutator equation, Price equation, and gradient dynamics in the infinite population limit. For finite populations, the equations describe the intricate interplay between natural selection, noise-induced selection, eco-evolutionary feedback, and neutral genetic drift in determining evolutionary trajectories. My work uses ideas from statistical physics, calculus of variations, and SPDEs, providing alternative methods that complement the measure-theoretic martingale approach that is more common in the literature.
title A stochastic field theory for the evolution of quantitative traits in finite populations
topic Populations and Evolution
Statistical Mechanics
Probability
Biological Physics
92D15 (Primary) 92D25, 60H15, 60J68, 60J70 (Secondary)
url https://arxiv.org/abs/2406.10739