Effects of phenotypic variation on consumer coexistence and prey community structure. (22nd November 2021)

• Record Type: Journal Article
• Authors: Hogle, Shane L.; Hepolehto, Iina; Ruokolainen, Lasse; Cairns, Johannes; Hiltunen, Teppo
• Editors: Chase, Jonathan
• Is Part Of: Ecology letters. Volume 25:Number 2(2022)
• Page Start: 307
• Page End: 319
• Publication Date: 2021-11-22
• Subjects: bacteria -- coexistence -- community assembly -- competition -- intraspecific variation -- nematodes -- predator -- prey -- protists -- traits; Ecology -- Periodicals; 577
• DOI: 10.1111/ele.13924
• Languages: English
• ISSNs: 1461-023X

Abstract

Abstract: A popular idea in ecology is that trait variation among individuals from the same species may promote the coexistence of competing species. However, theoretical and empirical tests of this idea have yielded inconsistent findings. We manipulated intraspecific trait diversity in a ciliate competing with a nematode for bacterial prey in experimental microcosms. We found that intraspecific trait variation inverted the original competitive hierarchy to favour the consumer with variable traits, ultimately resulting in competitive exclusion. This competitive outcome was driven by foraging traits (size, speed and directionality) that increased the ciliate's fitness ratio and niche overlap with the nematode. The interplay between consumer trait variation and competition resulted in non‐additive cascading effects—mediated through prey defence traits—on prey community assembly. Our results suggest that predicting consumer competitive population dynamics and the assembly of prey communities will require understanding the complexities of trait variation within consumer species. Abstract : How does intraspecific trait variation alter consumer competitive dynamics and prey community dynamics? We use synthetic microbial ecosystems to disentangle the interplay between consumer trait variation and competition using the framework of modern coexistence theory. Our results suggest that predicting consumer competitive population dynamics and the assembly of prey communities will require understanding the complexities of trait variation within consumer species.