Portal was the first Valve-developed game to be added to the OS X-compatible list of games available on the launch of the Steam client for Mac on May 12, 2010, supporting Steam Play, in which players that had bought the game either on a Macintosh or Windows computer could also play it on the alternate system.
1 Eurasian Pleistocene megafauna became extinct in roughly same time period despite having a much longer time to adapt to hunting pressure by humans. 2  However, the extinction of the Eurasian megafauna can be viewed as a result of a different process than that of the American megafauna.
Around 50,000 years ago, modern humans suddenly started leaving Africa. Over the course of the next 20,000 years, Homo sapiens pushed other hominid species to extinction and established populations in Australia, Asia, and Europe.round 50,000 years ago, modern humans suddenly started leaving Africa. Over the course of the next 20,000 years, Homo sapiens pushed other hominid species to extinction and established populations in Australia, Asia, and Europe.