Fig 1.
Distribution of (A) historical and contemporary estimated species richness of 51 medium- to large-bodied mammal species across the entire Caatinga dry forest of northeastern Brazil.
(B) Defaunation rates of these mammal species, ranging from 0 to 41 species, across the Caatinga as defined by the difference between reconstructed historical assemblages and observed contemporary assemblages. This map was prepared by the first author using the QGIS Madeira version 4.4.14 program and the geographic limits such as the limit of Caatinga and South America were taken from public database data from the Brazilian Institute of Geography and Statistics (IBGE https://www.ibge.gov.br/geociencias/organizacao-do-territorio/malhas-territoriais/15774-malhas.html).
Fig 2.
Aggregate mammal body mass of medium to large-bodied mammals per assemblage generated from potential species distribution models (blue histogram) and observed contemporary mammal assemblages (red histogram) across the Caatinga region.
(A) Sum of body mass of all co-occurring mammal species; and (B) Mean body mass of all co-occurring mammal species.
Fig 3.
Local extinction rates of medium- to large-bodied mammal species (A) and (B) orders across 73 mammal assemblages distributed throughout the Caatinga dry forest.
Bars are colour-coded according to species taxonomic order. Both species and orders are listed top to bottom from the highest to the lowest local extinction rates.
Fig 4.
Number of mammal species lost in the set of 73 assemblages distributed across dry forest areas of the Caatinga.
Each point refers to the set of assemblages with degrees of contemporary enforced protection based on (A) total biomass loss (kg) and (B) the total proportion of historical biomass retained at the time of each mammal inventory. The red dashed line separates losses from biomass gains. The gray area represents the confidence band around the black line generated by the generalized additive model (GAM).
Table 1.
Values generated by a general mixed-effects model, assessing whether aboveground biomass (AGB), protected areas, level of human footprint and defaunation influences functional diversity loss. P-values below the critical significance value (α = 0.05) are shown in bold.
Fig 5.
Loss in functional diversity across 73 mammal assemblages of the Caatinga semi-arid region of South America.
A) Relationship between functional diversity loss and defaunation rate according to the model generated. B) Relationship between functional diversity loss and the footprint of human disturbance. Both predictors are significant (p < 0.05) according to each model.
Fig 6.
Drivers of medium- to large-bodied mammal assemblages defaunation in the Caatinga.
A) Ranked feature importance values in terms of mean predictors of defaunation rates across the Caatinga region. B) Ranked feature importance values of predictors of defaunation for both negative (left) and (right) positive trends. Predictors are coded as follows: Livestock (ls), Crop (crop), Pasture (past), Aboveground Biomass (agb), Human footprint (hfp), and Protected Areas (pas).