Modeling the Distribution of Herpetofauna in the Brazilian Semiarid Region

Abstract

The Brazilian semi-arid housing the Caatinga biome, located between two humid biomes (Amazon and Atlantic Forests) and it is a region characterized by the presence of isolated humid environments, which represent important habitats for herpetofauna. This region underwent climate change in the Quaternary, with repercussions on the spatial distribution of humid forests. This study analyzed the distribution of herpetofauna species groups adapted to the humid enclaves of the Brazilian semiarid region based on species distribution modeling, focusing on the Last Interglacial (~120 kyr), Last Glacial Maximum (~22 kyr) and Middle Holocene (~6 kyr) periods. Paleoclimatic data available in WorldClim 1.4 were used in the study. The models showed good discriminatory capacity according to the groups analyzed (maximum temperature of the hottest month for lizards and snakes and annual precipitation for anurans), in addition to the high rainfall totals, which were important for all groups. Amphibians were more dependent on humid ecosystems, with their distribution impacted by drier periods. Lizards and snakes were more adaptable, with a greater distribution in these drier scenarios. These species had their range contracted between 35% (lizards) and 61% (snakes) in LIG, while amphibians had their range contracted by 73% compared to the current context.

Keywords: Species Distribution Modeling, Caatinga Biome, Quaternary Climate Change