Data from: A comparative analysis reveals little evidence for niche conservatism in aquatic macrophytes among four areas on two continents

One of the most intriguing questions in current ecology is the extent to
which the ecological niches of species are conserved in space and time.
Niche conservatism has mostly been studied using coarse-scale data of
species' distributions, although it is at the local habitat scales
where species' responses to ecological variables primarily take
place. We investigated the extent to which niches of aquatic macrophytes
are conserved among four study regions (i.e. Finland, Sweden and the US
states of Minnesota and Wisconsin) on two continents (i.e. Europe and
North America) using data for 11 species common to all the four study
areas. We studied how ecological variables (i.e. local, climate and
spatial variables) explain variation in the distributions of these common
species in the four areas using species distribution modelling. In
addition, we examined whether species' niche parameters vary among
the study regions. Our results revealed large variation in both
species' responses to the studied ecological variables and in
species' niche parameters among the areas. We found little evidence
for niche conservatism in aquatic macrophytes, though local environmental
conditions among the studied areas were largely similar. This suggests
that niche shifts, rather than different environmental conditions, were
responsible for variable responses of aquatic macrophytes to local
ecological variables. Local habitat niches of aquatic macrophytes are
mainly driven by variations in local environmental conditions, whereas
their climate niches are more or less conserved among regions. This
highlights the need to study niche conservatism using local-scale data to
better understand whether species' niches are conserved, because
different niches (e.g. local versus climate) operating at various scales
may show different degrees of conservatism. The extent to which
species' niches are truly conserved has wide practical implications,
including for instance, predicting changes in species' distributions
in response to global change.