Fig 1.
Summary of important events underlying the expansion of the diagonal of open/dry landscapes (DODL).
The location of the continuous ancient forest that was subsequently splitted into the actual Amazon and Atlantic forests (dashed green line) is based on Bigarella et al. [18]. Below the map, times and periods are based on Cohen et al. [25]. The asterisks indicate times established on the literature [9, 11, 26] with recent works contesting them [27–29]. Map source: Natural Earth (www.naturalearthdata.com).
Fig 2.
Regionalization scheme used in this study.
Biogeographical units are indicated by capital letters. Ecoregions or combinations of more than one ecoregion followed Olson et al. [63] and Dinerstein et al. [64] and were based on the present geographic range of Bothrops species. Images of Bothrops species are examples of some key species in each biogeographic unit. Photograph credits: Bruno Ferreto Fiorillo (Bothrops jararacussu), Marcio Martins (B. moojeni, B. diporus and B. erythromelas), Laurie J. Vitt (B. taeniata and B. venezuelensis), Conrado Mario da Rosa (B. pubescens), Herpetológica LAB from Mexico (B. asper), and Thibaud Aronson (B. chloromelas). Map source: Natural Earth (www.naturalearthdata.com).
Table 1.
Model comparisons on the ancestral range reconstruction of Bothrops forest clade performed with the phylogeny generated in this work.
d, e and w are free parameters in models where d is the rate of range expansion (i.e. dispersal), e is the rate of range contraction (i.e. extinction), and w is a dispersal multiplier parameter. As the time stratified matrix (TS models) were generated with arbitrary numbers, the “+w” models leave the w parameter free and the matrix itself is raised to the w parameter to seek the best dispersal multiplier values. Best models (DECTS and DIVALIKETS) are highlighted.
Fig 3.
Ancestral geographic ranges of the Bothrops forest clade reconstructed under the DIVALIKETS model.
Single capital letters indicate different biogeographic units used in this study. Mixed letters represent combinations of such units. Colors also represent biogeographic units. Combinations of two or more units are shown as a mixed colour made from all units in the combination. Units next to species names represent the current geographic distribution of each species. The green clade highlights the focal forest clade. Vertical dashed grey lines indicate the time slices defined in the time stratified matrix (see Methods). Letters in the corners of the cladogram represent the geographical range inherited from the ancestor immediately after a cladogenetic process. Focal nodes discussed in the text are numbered.
Fig 4.
Ancestral geographic range probabilities associated with the range reconstruction of Bothrops forest clade under the DIVALIKETS model.
Pie charts in nodes represent the geographic range probabilities of each hypothetical ancestor. Pie charts in the corners of the cladogram represent the geographical range probabilities inherited from the hypothetical ancestor immediately after a cladogenetic process. Colors represent biogeographical units. Units next to species names represent the current geographic distribution of each species. The green clade highlights the focal forest clade. Vertical dashed grey lines mark the time slices defined in the time stratified matrix. Focal nodes discussed in the text are numbered.