"Around two million years ago, a staggering ninety percent of the mammalian biomass in Africa and Asia was made up of elephants, hippos, and their rhinoceros-like buddies. This impressive lineup included at least nine species of elephants, four species of hippos, two species of rhinos, and a large cousin of the rhino-tapir-horse family known as Ancylotherium. The biggest shake-up in megafaunal species in Africa happened about 1.4 million years ago, roughly 300,000 years after Homo erectus made its debut and Australopithecus had disappeared. Since then, Africa and Asia have continued to experience megafaunal extinction events in fits and starts. Interestingly, during this two-million-year stretch, no large animal species went extinct on continents devoid of hominids, highlighting a unique and telling chapter in the evolutionary tale of the respective regions. The biodiversity of megafaunal species that roamed Europe and North America before humans showed up paints a fascinating picture—species like woolly mammoths, mastodons, and woolly rhinoceroses may have made up about 50% of the mammalian biomass in these regions. While this figure is less than what we saw in the Afroasian region, the megafaunal lineup in Europe and North America included some hefty ungulates that outclassed today’s bison in size. For instance, three species of bison, including the giant bison (Bison latifrons), were larger than the modern bison (Bison bison), but were swept away following the arrival of Homo sapiens. Although primary productivity remained unchanged with the extinction of the largest megafaunal animals, their loss created a vacuum that was quickly filled by a surge in populations of smaller critters, like bison and wildebeest. The absence of very large animals led to noticeably different effects on plants and soils, as more numerous smaller animals took their place. Overlooking the finite nature of the planet's primary productivity and the unique impacts of these smaller, more abundant species has fueled the persistence of [these] ecological myths […]. These misconceptions have led to a mixed bag of largely ineffective conservation efforts—some genuinely well-intentioned and others disingenuous."