Paleoclimate, ecoregion size, and degree of isolation explain regional biodiversity differences among terrestrial vertebrates within the Congo Basin


  • Frederik Van de Perre Evolutionary Ecology Group – University of Antwerp, 2020 Antwerp
  • Herwig Leirs Evolutionary Ecology Group – University of Antwerp, 2020 Antwerp
  • Erik Verheyen Evolutionary Ecology Group – University of Antwerp, 2020 Antwerp and Royal Belgian Institute of Natural Sciences, OD Taxonomy and Phylogeny, 1000 Brussels



biodiversity, rainforest, conservation, refuge theory, species accumulation curves


One of the most widely recognized patterns in ecology is the increase in species richness from poles to tropics. Literature suggests that the Congolian lowland rainforest does not follow this pattern: the Central Congolian forest (CCLF), south of the Congo River, is thought to harbor fewer vertebrate species and endemics than the Northeastern (NELF) and Northwestern lowland rainforests (NWLF) north of the Congo River. We used data from the Global Biodiversity Information Facility (GBIF) database on terrestrial vertebrates (mammals, birds, and reptiles), to test whether differences in sampling effort caused the irregular biodiversity pattern in this region. Our results show that even though the diversity within the Congolian lowland rainforests remains to be fully mapped, current differences in richness are unlikely to be caused by undersampling alone. We argue that the lower vertebrate richness in the CCLF is due to both its relatively small size and isolated position: Forest cover fluctuated throughout the history of the Congo Basin due to climatic variability, reducing speciation and increasing extinction, while immigration towards the CCLF is limited due to the barrier effect of the Congo River. The implications of these findings are discussed in the context of both fundamental ecology and conservation management.


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How to Cite

Van de Perre, F., Leirs, H., & Verheyen, E. (2019). Paleoclimate, ecoregion size, and degree of isolation explain regional biodiversity differences among terrestrial vertebrates within the Congo Basin. Belgian Journal of Zoology, 149.