Purring Monkeys!

~Among 441 new species discovered in the Amazon jungle between 2010 and 2013 is a new species of titi monkey, Callicebus caquetensis.  Baby monkeys of this species exhibit a behavior not seen before in other species of monkey: when content, they purr!

Read the whole story (and about some of the other species discovered) here:

http://www.sciencedaily.com/releases/2013/10/131025085909.htm