New article: Biogeography of species richness gradients.

In a new article published in Biological reviews, Lluís Brotons together with other CREAF researchers led by Jofre Carnicer, shed light on how adaptive traits contribute to the emergence and maintenance of species richness gradients.

Empirical studies show that geographical clines in population parameters and measures of demographic variability are frequent along latitudinal and altitudinal gradients. Demographic variability often increases at the extremes of regional species richness gradients and contributes to shape these gradients. Available studies suggest that adaptive traits significantly influence demographic dynamics, and set the limits of species distributions. Traits related to thermal tolerance, resource use, phenology and dispersal seem to play a significant role.

For many traits affecting demography and/or diversification processes, complex mechanistic approaches linking genotype, phenotype and fitness are becoming progressively available. In several taxa, species can be distributed along adaptive trait continuums.

Finally, the review deals with the existence of sequences of adaptive traits in phylogenies, the interactions of adaptive traits and community context, the clinal variation of traits across geographical gradients, and the role of adaptive traits in determining the history of dispersal and diversification of clades. Overall, the available evidence suggest that the study of demographic and evolutionary mechanisms that shape species richness gradients clearly requires the explicit consideration of adaptive traits.

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Biogeografia dels gradients de riquesa d’espècies

En un nou article publicat a la revista Biological Reviews, Lluís Brotons amb altres investigadors del CREAF liderats per en Jofre Carnicer s’investiga com els trets evolutius contribueixen a l’emergència i manteniment dels gradients de riquesa d’espècies. 

Per exemple, els estudis empírics suggereixen que els paramètres demogràfics mostren clines geogràfiques en paral.lel a la variabilitat en gradients latitudinals i altitudinals. La variabilitat demografica sovint augmenta en els extrems dels gradients regionals de riquesa contribuint així al manteniment d’aquests gradients.

Carnicer, J., Brotons, L. Stefanescu, C. & Peñuelas, J. (in press) Biogeography of species richness gradients: linking adaptive traits, demography and diversification. Biological Reviews.