Richness patterns in vertebrates are robust to the Linnean and Wallacean shortfalls

Abstract

Nearly all research has to rely on imprecise data. This poses a challenge of knowing which conclusions are reliable despite potential data quality issues. One field that has been fundamentally affected by this is macroecology. Can we understand drivers of biodiversity patterns without having fully reliable distributional data? In this paper, we investigated the reliability of biodiversity patterns focused on three groups of terrestrial vertebrates ranging from very well known (birds and mammals) to relatively poorly known (amphibians). We compared two expert-derived sets of range maps generated more than 10 years apart. We found that nearly half of all species had changes in taxonomy and/or distribution, but despite this, the overall spatial diversity patterns between the two sets were extraordinarily similar for all three groups. We further found that the minute changes in richness we saw were almost exclusively driven by changes in the mapped ranges of already known species rather than the discovery of new species, even though up to 18% of new species were added between assessments. Since the patterns were highly similar between the assessments, this suggests that, at least for vertebrates, data quality does not affect analyses of biodiversity patterns. This further implies that results based on older and less precise input data remain reliable, even though more precise input data have become available.