Niche conservatism and dispersal limitation cause large-scale phylogenetic structure in the New World palm flora

TY - ABST

T1 - Niche conservatism and dispersal limitation cause large-scale phylogenetic structure in the New World palm flora

AU - Eiserhardt, Wolf L.

AU - Svenning, J.-C.

AU - Baker, William J.

AU - Couvreur, Thomas L.P.

AU - Balslev, Henrik

PY - 2011/4/16

Y1 - 2011/4/16

N2 - We studied the role of evolutionary history in shaping the geographic distributions of palm species in the Americas. The distributions of any two extant species have “evolved” from the distribution of their most recent common ancestor, and are thus not independent. How fast distributional similarity decays after speciation depends on the rates of niche evolution and dispersal. If dispersal is slow compared to the tempo of lineage diversification, distributions change little during clade diversification. Phylogenetic niche conservatism precludes distributional shifts in environmental space, and to the degree that distributions are limited by the niche, also in geographic space. Using phylogenetic turnover methods, we simultaneously analysed the distributions of all New World palms (n=547) and inferred to which degree phylogenetic niche conservatism and dispersal limitation, respectively, caused closely related species to have similar distributions. The phylogenetic relatedness of assemblages decreased both with increasing environmental dissimilarity and geographical distance, indicating that distributions are significantly influenced by macro-evolutionary processes. These include phylogenetically conserved tolerances to temperature extremes and seasonality as well as dispersal limitation on evolutionary timescales. Niche dimensions that are phylogenetically conserved are not necessarily the ones that are thought to be most important for controlling contemporary species distributions (e.g., water availability)

AB - We studied the role of evolutionary history in shaping the geographic distributions of palm species in the Americas. The distributions of any two extant species have “evolved” from the distribution of their most recent common ancestor, and are thus not independent. How fast distributional similarity decays after speciation depends on the rates of niche evolution and dispersal. If dispersal is slow compared to the tempo of lineage diversification, distributions change little during clade diversification. Phylogenetic niche conservatism precludes distributional shifts in environmental space, and to the degree that distributions are limited by the niche, also in geographic space. Using phylogenetic turnover methods, we simultaneously analysed the distributions of all New World palms (n=547) and inferred to which degree phylogenetic niche conservatism and dispersal limitation, respectively, caused closely related species to have similar distributions. The phylogenetic relatedness of assemblages decreased both with increasing environmental dissimilarity and geographical distance, indicating that distributions are significantly influenced by macro-evolutionary processes. These include phylogenetically conserved tolerances to temperature extremes and seasonality as well as dispersal limitation on evolutionary timescales. Niche dimensions that are phylogenetically conserved are not necessarily the ones that are thought to be most important for controlling contemporary species distributions (e.g., water availability)

M3 - Conference abstract for conference

T2 - EUNOPS 11

Y2 - 16 April 2011 through 17 April 2011

ER -