This suggests that, rather than arising in East Africa approximately 200,000 years ago, modern humans may have been present across the length of Africa 100,000 years earlier. According to study author Jean-Jacques Hublin, "The idea is that early "Homo sapiens" dispersed around the continent and elements of human modernity appeared in different places, and so different parts of Africa contributed to the emergence of what we call modern humans today." Early humans may have comprised a large, interbreeding population dispersed across Africa whose spread was facilitated by a wetter climate that created a "green Sahara", approximately 330,000 to 300,000 years ago. Thus, the rise of modern humans may have taken place on a continental scale rather than being confined to a particular corner of Africa.