From Metapopulation to Metacommunity and the Complications of Community Structure

Hajian-Forooshani, Z.; Schmitt, L.; Medina, N.; Vandermeer, J.

doi:10.1101/504670

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bioRxiv · 10.1101/504670

From Metapopulation to Metacommunity and the Complications of Community Structure

Hajian-Forooshani, Z.·Schmitt, L.·Medina, N.·Vandermeer, J.

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Abstract

The metacommunity, as it evolved from Levins metapopulation, provides a framework to consider the spatial organization of species interactions. Arguably the most fundamental feature of metapopu-lations and metacommunities are that demes are connected via migration. An important result from Levins metapopulation work--that increasing migration lowers regional extinction probability--is often incorporated into conceptions of metacommunities. We first use a toy model to show how this result from Levins metapopulation does not necessarily hold when considering community interactions in a metacommunity context. We also report results from a metacommunity field experiment conducted with a tropical terrestrial leaf litter community and show that migration induces the extinction of predators in the metacommunity. Our result corroborates the findings of a prior metacommunity experiment in a temperate terrestrial leaf litter community. The concordance between these experiments even with vastly different communities highlights the importance of considering trophic and non-trophic community structure to understand metacommunity dynamics.

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Hajian-Forooshani, Z., Schmitt, L., Medina, N., Vandermeer, J.. 2018-12-23. From Metapopulation to Metacommunity and the Complications of Community Structure. https://doi.org/10.1101/504670

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