Spatio-temporal Moran dynamics in continuous media

Fuente: arXiv
Guardado en:
Detalles Bibliográficos
Autores principales: Gorgi, Melika, Kaveh, Kamran, Aliakbarian, Navid, Ejtehadi, Mohammad Reza
Formato: Preprint
Publicado: 2025
Materias:
Acceso en línea:
Etiquetas: Agregar Etiqueta
Sin Etiquetas, Sea el primero en etiquetar este registro!
_version_ 1866914203628994560
author Gorgi, Melika
Kaveh, Kamran
Aliakbarian, Navid
Ejtehadi, Mohammad Reza
author_facet Gorgi, Melika
Kaveh, Kamran
Aliakbarian, Navid
Ejtehadi, Mohammad Reza
contents Understanding how natural selection unfolds across space and time is a central problem in evolutionary biology. Classic models such as the Moran process capture stochastic birth-death dynamics in structured populations, while reaction-diffusion equations like the Fisher-Kolmogorov-Petrovsky-Piskunov (FKPP) equation describe deterministic wave-like spread. In this work, we bridge these perspectives by deriving partial differential equations for the spatiotemporal limit of Moran dynamics in continuous media. Our model incorporates two distinct fitness components: fecundity (birth rate) and viability (death rate). We demonstrate that the resulting selective wave speeds differ substantially in spatial Moran Birth-death (Bd), Moran Death-birth (Db), and FKPP dynamics. When fecundity drives the dynamics, we observe that the selective waves decelerate for the Bd process, whereas in the Db process the wave propagates with a higher, constant speed. In contrast, when viability drives the process, the Db wave accelerates, while the Bd and FKPP waves maintain comparable constant speeds. We extend the framework to heterogeneous media, represented as weighted lattice graphs in one or two dimensions. We derive a continuous space analog of isothermal graphs and establish that the isothermality condition corresponds to the conservation of a local current.
format Preprint
id arxiv_https___arxiv_org_abs_2512_14171
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Spatio-temporal Moran dynamics in continuous media
Gorgi, Melika
Kaveh, Kamran
Aliakbarian, Navid
Ejtehadi, Mohammad Reza
Populations and Evolution
Mathematical Physics
Understanding how natural selection unfolds across space and time is a central problem in evolutionary biology. Classic models such as the Moran process capture stochastic birth-death dynamics in structured populations, while reaction-diffusion equations like the Fisher-Kolmogorov-Petrovsky-Piskunov (FKPP) equation describe deterministic wave-like spread. In this work, we bridge these perspectives by deriving partial differential equations for the spatiotemporal limit of Moran dynamics in continuous media. Our model incorporates two distinct fitness components: fecundity (birth rate) and viability (death rate). We demonstrate that the resulting selective wave speeds differ substantially in spatial Moran Birth-death (Bd), Moran Death-birth (Db), and FKPP dynamics. When fecundity drives the dynamics, we observe that the selective waves decelerate for the Bd process, whereas in the Db process the wave propagates with a higher, constant speed. In contrast, when viability drives the process, the Db wave accelerates, while the Bd and FKPP waves maintain comparable constant speeds. We extend the framework to heterogeneous media, represented as weighted lattice graphs in one or two dimensions. We derive a continuous space analog of isothermal graphs and establish that the isothermality condition corresponds to the conservation of a local current.
title Spatio-temporal Moran dynamics in continuous media
topic Populations and Evolution
Mathematical Physics
url https://arxiv.org/abs/2512.14171