Data from: Range shifting species reduce phylogenetic diversity in high latitude communities via competition

Under anthropogenic climate change, many species are expanding their
ranges to higher latitudes and altitudes, resulting in novel species
interactions. The consequences of these range shifts for native species,
patterns of local biodiversity, and community structure in high latitude
ecosystems are largely unknown but critical to understand in light of
widespread poleward expansions by many warm-adapted generalists. Using
niche modelling, phylogenetic methods, and field and laboratory studies,
we investigated how colonisation of Scotland by a range expanding
damselfly, Ischnura elegans, influences patterns of competition and niche
shifts in native damselfly species, and changes in phylogenetic community
structure. Colonization by I. elegans was associated with reduced
population density and niche shifts in the resident species least related
to I. elegans (Lestes sponsa), reflecting enhanced competition.
Furthermore, communities colonized by I. elegans exhibited phylogenetic
underdispersion, reflecting patterns of relatedness and competition. Our
results provide a novel example of a potentially general mechanism whereby
climate change-mediated range shifts can reduce phylogenetic diversity
within high latitude communities, if colonising species are typically
competitively superior to members of native communities that are
least-closely-related to the coloniser.