The most comprehensive guide to primates, released this week, names the "five funniest faces" in the monkey world. The massive guide, "Handbook of the Mammals of the World" (Lynx Edicions, 2013), contains information on the 16 families, 77 genera, 479 species and 681 taxa of primates.
Number one on the book's list of funniest faced monkeys is the emperor tamarin. Editors Russell Mittermeier, Anthony Rylands and Don Wilson mention that this monkey was "named after Emperor Franz Joseph of Austria." Members of the species "have a white curved 'mustache' hanging down as far as their chest." The mustache is thought to aid in visual communication.
"Proboscis" is the scientific term for certain mammals' noses. The shnoz on the proboscis monkey is certainly hard to miss. Noses on males can exceed 4 inches in length, hanging lower than the mouth.
Mittermeier, Rylands and Wilson explained that "their long nose is used as a resonating chamber for its loud honking calls."
"Tarsiers must have been the inspiration for Yoda in Star Wars," according to the editors. "They have huge forward facing eyes, each larger than their brain."
These nocturnal, insect-eating primates need such eyes to locate prey and other things in the dark. They live on islands of Southeast Asia.
The researchers mention that bearded sakis "display an extraordinary beard and bouffant hairstyle." Five species have this unique look, all classified in the genus Chiropotes. The one shown here is Uta Hick's bearded saki, native to Brazil.
Black-and-white colobus monkeys "always look disgruntled," according to the editors. That's just the way they look, although they have plenty to be perturbed about.
These plant-eaters are prey for many forest predators, including humans. They have also suffered due to logging practices and habitat destruction. This individual appears to have been captured in a particularly non-cranky moment, nibbling on a leaf.