Effects of phenotypic variation on consumer coexistence and prey community structure




Hogle Shane L., Hepolehto Iina, Ruokolainen Lasse, Cairns Johannes, Hiltunen Teppo

PublisherWILEY

2022

Ecology Letters

ECOLOGY LETTERS

ECOL LETT

25

2

307

319

13

1461-023X

1461-0248

DOIhttps://doi.org/10.1111/ele.13924(external)

https://doi.org/10.1111/ele.13924(external)

https://research.utu.fi/converis/portal/detail/Publication/68056681(external)



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.

Last updated on 2024-26-11 at 13:40