ALBERT

Beschreibung: Abstract Aim Although various theories have been proposed to explain the outstanding endemism of plants in the Cerrado, four hypotheses about the mechanisms of diversification and distribution are most supported: (a) plateau/valley, (b) stable/unstable climate, (c) core/peripheral distribution, and (d) soil fertility. The first argues that plateaus harbour more ancient lineages than valleys and therefore present higher endemism. The second theory suggests that climatically stable environments maintained more palaeoendemic species. The third scenario attributes the distribution of endemism to gradients of conditions available to locally adapted species and predicts higher endemism in nuclear than in marginal areas. The last theory suggests that soils with lower fertility account for higher endemism owing to the habitat specialization of their species. We compared endemism patterns with the predictions of each theory to discuss their importance. Location Brazil. Time period Quaternary. Major taxa studied Angiosperms. Methods We mapped the endemism using records of 311 plant species of the Cerrado and applied spatial analysis and distribution models to summarize the importance of each predictor of endemism. Results We identified 28 areas in which the higher endemism of Cerrado plants were concentrated and presented a map of their distribution. We found correlations among endemism, climate stability, elevation and marginality, which supported the plateau/valley, core/peripheral and stable/unstable hypotheses. No association between soil fertility and endemism was detected. We propose that plateaus are more stable climatic environments, and this characteristic along with their elevation and centrality are predictive of endemism. Main conclusions We concluded that most of the endemism is concentrated in overlapping areas of stability of species, which are concentrated in higher elevation central regions. Soil fertility was not linked to endemism. We recommend that central plateaus in the Cerrado require special attention in conservation to optimize the protection of endemic species in the biome.