Abstract
An important aspect of the current extinction crisis is the loss of distinct clades (e.g., genera). A recent study suggested that there is rapidly accelerating extinction of genera (and other higher taxa), indicating a current mass extinction event that endangers human survival. However, that study was based only on land vertebrates, which include only about half of vertebrates and <2% of living species. Here, we examine the recent extinction (last 500 years) of higher taxa across living organisms. We find that 102 genera have gone extinct (90 animals, 12 plants), along with 10 families and two orders. Yet, the majority of these genus-level extinctions were among mammals and birds, as were all extinctions of families and orders. There were very few extinctions among the thousands of genera of ray-finned fishes (n = 4; 0.08%), squamate reptiles (n = 2; 0.17%), and amphibians (n = 1; 0.18%). Documented extinctions were also rare among the thousands of assessed genera of arthropods (n = 11; 0.32%) and plants (n = 12; 0.17%), which together encompass most known species. Most extinct genera were monotypic (~80%), and most were island endemics (76%). Moreover, despite the claim that extinctions of higher taxa are rapidly accelerating, the highest rates of genus-level extinctions occurred more than 100 years ago, and have declined subsequently. Overall, the recent extinctions of higher taxa are not as dire as previously suggested.