Without humans, the whole world could look like Serengeti

The fact that the greatest diversity of large mammals is found in Africa reflects past human activities -- and not climatic or other environmental constraints. This is determined in a new study, which presents what the world map of mammals would look like if modern man (Homo sapiens) had never existed. In a world without humans, most of northern Europe would probably now be home to not only wolves, Eurasian elk (moose) and bears, but also animals such as elephants and rhinoceroses. This is demonstrated in a new study conducted by researchers from Aarhus University, Denmark. In a previous analysis, they have shown that the mass extinction of large mammals during the Last Ice Age and in subsequent millennia (the late-Quaternary megafauna extinction) is largely explainable from the expansion of modern man (Homo sapiens) across the world. In this follow-up study, they investigate what the natural worldwide diversity patterns of mammals would be like in the absence of past and present human impacts, based on estimates of the natural distribution of each species according to its ecology, biogeography and the current natural environmental template. They provide the first estimate of how the mammal diversity world map would have appeared without the impact of modern man. "Northern Europe is far from the only place in which humans have reduced the diversity of mammals -- it's a worldwide phenomenon. And, in most places, there's a very large deficit in mammal diversity relative to what it would naturally have been," says Professor Jens-Christian Svenning, Department of Bioscience, Aarhus University, who is one of the researchers behind the study.


http://www.sciencedaily.com/releases/2015/08/150820212652.htm