A framework for elucidating the temperature dependence of fitness
Therefore, while climate change brings many difficulties in establishing a general understanding of species vulnerability, these findings emphasize how combining trait-based approaches in light of the species evolutionary history may offer new opportunities in facing conservation challenges..Throughout their evolutionary (that is, phylogenetic) history, species have been continuously exposed to climate fluctuations.
We demonstrate that these shifts are related to dissimilar mechanisms: whereas range retractions show some support for phylogenetic clustering due to a high level of conservatism in thermal safety margins, range expansions are underpinned by both evolutionarily conserved and labile traits, notably trophic position and life-history strategy, hence decreasing the strength of phylogenetic signal.Branch colours indicate ancestral state reconstructions of the rate of climate-induced shifts in lower altitudinal limit along the edges and internal nodes of the tree, with dark colours indicating the stronger shifts.The scale bar indicates the divergence time estimates for the phylogenetic reconstruction in millions of years before present.Indeed, morphological traits linked to dispersal ability (for example, mobility through body size) are commonly conserved along the phylogeny, whereas several behavioural and ecological traits related to establishment success (for example, degree of habitat specialization should decrease habitat available for the species) are thought to be more evolutionarily labile.Consequently, we expected to find little or no phylogenetic clustering of range expansion at the leading edge.
Search for a framework for elucidating the temperature dependence of fitness:
Nevertheless, propagule pressure (that is, the quantity and frequency of dispersing individuals) may enable species to temporarily compensate for local extinctions caused by adverse climatic conditions.