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.
Woolly Mammoths in the northernmost areas had hair up to three feet long, and curly tusks up to five feet long. Mammoth survived longer than other Ice Age giants, with the biggest extinction occurring about 8,000 years ago. A dwarf species survived on Wrangel Island near Siberia until about 1700 BC. (Image: Mauricio Anton). The dinosaurs got really big, and they died out. Pleistocene mammals grew very big, and they died out.