Regulation of community functional composition across taxonomic variation by resource-consumer dynamics

TL;DR

This paper uses ecological models to show how resource-consumer interactions can stabilize the functional traits of microbial communities, maintaining their ecological roles despite taxonomic variability.

Contribution

It introduces a mathematical framework demonstrating how resource-consumer dynamics regulate functional composition across diverse microbial communities.

Findings

Functional traits remain stable despite taxonomic changes.

Community functional composition faithfully tracks environmental differences.

Mathematical conditions for trait conservation are provided.

Abstract

High-throughput sequencing techniques such as metagenomic and metatranscriptomic technologies allow cataloging of functional characteristics of microbial community members as well as their taxonomic identity. Such studies have found that a community's composition in terms of ecologically relevant functional traits or guilds can be conserved more strictly across varying settings than taxonomic composition is. I use a standard ecological resource-consumer model to examine the dynamics of traits relevant to resource consumption, and analyze determinants of functional composition. This model demonstrates that interaction with essential resources can regulate the community-wide abundance of ecologically relevant traits, keeping them at consistent levels despite large changes in the abundances of the species housing those traits in response to changes in the environment, and across variation between communities in species composition. Functional composition is shown to be able to track differences in environmental conditions faithfully across differences in community composition. Mathematical conditions on consumers' vital rates and functional responses sufficient to produce conservation of functional community structure across taxonomic differences are presented.