Environment determines evolutionary trajectory in a constrained phenotypic space

Constraints on phenotypic variation limit the capacity of organisms to adapt to the multiple selection pressures encountered in natural environments. To better understand evolutionary dynamics in this context, we select Escherichia coli for faster migration through a porous environment, a process which depends on both motility and growth. We find that a trade-off between swimming speed and growth rate constrains the evolution of faster migration. Evolving faster migration in rich medium results in slow growth and fast swimming, while evolution in minimal medium results in fast growth and slow swimming. In each condition parallel genomic evolution drives adaptation through different mutations. We show that the trade-off is mediated by antagonistic pleiotropy through mutations that affect negative regulation. A model of the evolutionary process shows that the genetic capacity of an organism to vary traits can qualitatively depend on its environment, which in turn alters its evolutionary trajectory.

Abstract licence: CC BY

1. 34.

   A Comprehensive Genetic Characterization of Bacterial Motility · 2007

2. 36.
   Corrected

   Structure and Evolution of Streptomyces Interaction Networks in Soil and In Silico · 2011

3. 59.

   Experimental evolution reveals hidden diversity in evolutionary pathways · 2015

4. 63.

   High-throughput 3D tracking of bacteria on a standard phase contrast microscope · 2015

5. 65.
   Retracted

   A mathematical model explains saturating axon guidance responses to molecular gradients · 2016

68 more references, whose wording the paper’s licence keeps private.

• Multiple functions of flagellar motility and chemotaxis in bacterial physiology · 2021

A person counts once a day per paper. We keep no cookie and no address: a reader is a hash that changes every day. Any month under five reads shows no number.