Biodiversity offers diverse ecosystem services responsible for increasing human well-being and moving financial capital around the world. Therefore, given the natural and human causes of biodiversity reduction, we need to use conservation prioritization methods that not only show where to find high species richness, but also low economic cost. In this paper, we suggest priority areas, on a global scale, for the conservation of terrestrial and flying mammals and the Serpentes, an endothermic group. We do that by finding high potential for providing ecosystem services (measured here by Species Richness) and correlating it with Economic Cost (measured as Land Acquisition Cost). To achieve this goal, we first developed the ‘bivariatemaps’ package, using it to plot bivariate maps that integrate the Species Richness with the Land Cost for each of the three studied groups. We observe that more attention should be paid to tropical countries, which have high species richness, but low land acquisition cost. We note that more attention should be paid to the Indomalayan region, which has a high richness of species low-cost sites for the conservation of species. Bivariate maps have been published in studies since the 70s, but only in the 2010s they became more used by the general public, including scientists from low-profit universities. We hope that this paper (and the ‘bivariatemaps’ package) helps to generate works planned globally and regionally in the face of natural and anthropogenic processes responsible for the loss of biodiversity that can bring us socio-economic benefits.

In this study, we sought to understand how the Linnean shortfall (i.e., the lack of knowledge about species taxonomy) interacts with the Darwinian shortfall (i.e., the lack of knowledge about phylogenetic relationships among species), potentially jeopardizing geographical patterns in estimates of speciation rates, using New World coralsnakes as a case study. For this purpose, we created an index of taxonomic uncertainty that measures the likelihood of current species being split after undergoing future taxonomic revisions. Next, we conducted simulations in which branches of species with high taxonomic uncertainty are split in the phylogenetic trees to generate new hypothetical species along their geographic ranges. We found that a high number of coralsnake species display substantial taxonomic uncertainty, positively correlated with the latitude of the species’ geographical range centroid. The estimated speciation rates based on currently available data have a weak relationship with latitude. However, after incorporating taxonomic uncertainty into the phylogeny, we detect a higher positive correlation between speciation rate and latitude. This shift demonstrates that taxonomic uncertainty can undermine empirical evaluation of the geographical pattern estimates in speciation rates, revealing an interaction between the latitudinal taxonomic gradient and the latitudinal diversity gradient. Given that taxonomic changes can alter the number of species recognized as valid over time, our study highlights the need to incorporate taxonomic uncertainty into macroecological and macroevolutionary studies, enhancing the robustness of patterns inferred from these data.