Statistical Fluctuations in Evolutionary and Population Dynamics

DSpace/Manakin Repository

Statistical Fluctuations in Evolutionary and Population Dynamics

Citable link to this page

 

 
Title: Statistical Fluctuations in Evolutionary and Population Dynamics
Author: Chotibut, Thiparat ORCID  0000-0002-8936-1413
Citation: Chotibut, Thiparat. 2016. Statistical Fluctuations in Evolutionary and Population Dynamics. Doctoral dissertation, Harvard University, Graduate School of Arts & Sciences.
Full Text & Related Files:
Abstract: In this thesis, we study collective phenomena that arise from microscopic fluctuations at the individual level of two different living populations. First, we study evolutionary dynamics of two-species competitions in a well-mixed environment subject to population size fluctuations. We demonstrate a mechanism for neutral evolution such that population size fluctuations favor a fixation of one species over the other. An effective evolutionary dynamics for fluctuation-induced selection is derived. We then investigate strong mutualism, in a limit where a varying population size can strongly influence the evolutionary dynamics. We determine fixation probabilities as well as mean fixation times taking into account the population size degree of freedom. The results elucidate the interplay between population size fluctuations and evolutionary dynamics in well-mixed systems. Second, we investigate  single species marine population  subject to a constant flow field and quenched random spatially fluctuating growth rates.  We show that the non-equilibrium steady-state population density of a generalized Fisher-Kolmogorov-Petrovsky-Piscounov (FKPP) equation develops a flow-driven striation pattern.  The striations are highly asymmetric with a longitudinal correlation length that diverges linearly with the flow speed and a transverse correlation length that approaches a finite velocity-independent value. The findings suggest that, although the growth disorder can be spatially uncorrelated, correlated population structures with striations emerge naturally at sufficiently strong advection.
Terms of Use: This article is made available under the terms and conditions applicable to Other Posted Material, as set forth at http://nrs.harvard.edu/urn-3:HUL.InstRepos:dash.current.terms-of-use#LAA
Citable link to this page: http://nrs.harvard.edu/urn-3:HUL.InstRepos:33493257
Downloads of this work:

Show full Dublin Core record

This item appears in the following Collection(s)

 
 

Search DASH


Advanced Search
 
 

Submitters