Alfred Russel Wallace,
The Malay Archipelago, Volume 1
“ It is very remarkable that an animal so large, so peculiar, and of such a high type of form as the Orangutan, should be confined to so limited a district—to two islands, and those almost the last inhabited by the higher Mammalia; for, east of Borneo and Java, the Quadrumania, Ruminants, Carnivora, and many other groups of Mammalia diminish rapidly, and soon entirely disappear. ”
