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.
However, the cause of these extinctions is no mystery. We know what is driving this rapid decline of species. Biodiversity loss due to climate change, habitat loss, pollution, and overfishing, tops the list as the main culprits of the impending extinction, all causes initiated by human industry.