Growth rate evolution in improved environments under Prodigal Son dynamics

Authored by Sinead Collins

Date Published: 2016

DOI: 10.1111/eva.12403

Sponsors: European Union Royal Society

Platforms: R

Model Documentation: Other Narrative Mathematical description

Model Code URLs: http://onlinelibrary.wiley.com/store/10.1111/eva.12403/asset/supinfo/eva12403-sup-0001-SupInfo.R?v=1&s=69eeab820a4f5e585a789b581675d21eca1ff6ca

Abstract

I use an individual-based model to investigate the evolution of cell division rates in asexual populations under chronic environmental enrichment. I show that maintaining increased growth rates over hundreds of generations following environmental improvement can be limited by increases in cellular damage associated with more rapid reproduction. In the absence of further evolution to either increase damage tolerance or decrease the cost of repair or rate of damage, environmental improvement does not reliably lead to long-term increases in reproductive rate in microbes. Here, more rapid cell division rates also increases damage, leading to selection for damage avoidance or repair, and a subsequent decrease in population growth, which I call Prodigal Son dynamics, because the consequences of `living fast' force a return to ancestral growth rates. Understanding the conditions under which environmental enrichment is expected to sustainably increase cell division rates is important in applications that require rapid cell division (e.g. biofuel reactors) or seek to avoid the emergence of rapid cell division rates (controlling biofouling).

Tags

Adaptation microorganisms Populations Stress Chlamydomonas-reinhardtii Elevated co2 Alga