Detecting the ecological footprint of selection

Abstract

The structure of communities is influenced by many processes, both ecological and evolutionary, but these processes are hard to distinguish from available data. The aim of this work is to distinguish the ecological footprint of selection from that of neutral processes that are invariant to species identity. To do this, we build on existing theory to produce a new mechanistic model of community structure incorporating ecology and evolution. We base our work on "massive eco-evolutionary synthesis simulations" (or MESS), which uses information from three biodiversity axes - species richness and abundance; population genetic diversity; and trait variation - to distinguish between processes with a mechanistic model. We added a new form of competition to MESS that explicitly compares the traits of each pair of individuals and allows us to distinguish between inter- and intra-specific competition. We find that this addition is essential to properly detect and characterise selection and it yields different results to the existing simpler model that only compares species' traits to the community mean. Neutral forces receive much less support from systems where trait data is incorporated into the inference mechanism.

Inferring the ecological and evolutionary determinants of community genetic diversity

“…An allometric theory may be introduced by conditioning colonization rate and probability of local extinction on trait values (again imagining the focal trait as body size; Jacquet et al, 2017). Future work may also incorporate more biologically relevant non‐neutral models which represent competition as pairwise among lineages (Luiselli et al, 2021). From a strictly operational perspective, both the Hill number summarization and the computationally efficient sorting procedure result in breaking the connection between the phylogeny and the other axes of local data (abundances, traits and genetic diversities).…”

Information‐based summary statistics for spatial genetic structure inference

“…Integrative studies of species and genetic diversity, and the ecological factors underlying their association or lack thereof using the same type of index, would contribute to a better understanding of eco-evolutionary dynamics. Although not focused on spatial scenarios, some recent studies (Gaggiotti et al, 2018;Luiselli et al, 2021;Overcast et al, 2019Overcast et al, , 2021 have developed a community assembly model that makes predictions of genetic, species and functional diversity in terms of Hill numbers.…”