Late Quaternary climate legacies in contemporary plant functional composition

Abstract

The functional composition of plant communities is commonly thought to be determined by contemporary climate. However, if rates of climate-driven immigration and/or exclusion of species are slow, then contemporary functional composition may be explained by paleoclimate as well as by contemporary climate. We tested this idea by coupling contemporary maps of plant functional trait composition across North and South America to paleoclimate means and temporal variation in temperature and precipitation from the Last Interglacial (120 ka) to the present. Paleoclimate predictors strongly improved prediction of contemporary functional composition compared to contemporary climate predictors, with a stronger influence of temperature in North America (especially during periods of ice melting) and of precipitation in South America (across all times). Thus, climate from tens of thousands of years ago influences contemporary functional composition via slow assemblage dynamics.

Robustness of trait connections across environmental gradients and growth forms

“…A number of studies have used the BHPMF method in other trait analyses with robust results (see Blonder et al, 2018;Caplan, Meiners, Flores-Moreno, & McCormack, 2018;Díaz et al, 2016;Moreno-Martínez et al, 2018). Nonetheless, we also checked the robustness of the BHPMF algorithm by comparing the trait-trait relationship from 1,000 gap-filled datasets versus trait-trait correlations only from the original dataset (Supporting Information Figure S1.1, and determining the correlation between the accuracy (RMSE) and confidence (SD) of the algorithm using our dataset (Supporting Information Figure S1.2.…”

A process‐based model supports an association between dispersal and the prevalence of species traits in tropical reef fish assemblages

“…For example, Leprieur et al (2016) showed how the dynamics of shallow reefs influenced the diversification of tropical marine organisms in space and time. The drivers underlying the global variation in species trait composition within assemblages are only starting to be explored and may not always correspond to those of species richness (Blonder et al 2018). The drivers underlying the global variation in species trait composition within assemblages are only starting to be explored and may not always correspond to those of species richness (Blonder et al 2018).…”

“…However, while research has largely focused on gradients in species richness (Mittlebach et al 2007), biodiversity also integrates trait or phylogenetic diversity components in assemblages, which are not always spatially congruent (Devictor et al 2010). The drivers underlying the global variation in species trait composition within assemblages are only starting to be explored and may not always correspond to those of species richness (Blonder et al 2018). Therefore, there is growing interest to assess whether processes that have shaped species richness have also influenced the spatial distribution of species traits.…”

Disequilibrium in Trait-Climate Relationships of Trees and Birds

“…These include shifts in relative abundance of resident species, local extirpation, and colonization by new species. However, these dynamics may be slow relative to the pace of changing conditions, in which case past conditions will leave a legacy on current composition (Svenning and Sandel, 2013;Blonder et al, 2018). For example, after a particular change in conditions, species that are no longer well adapted may maintain a sink population at a site for years or even centuries.…”