Pygmy Marmoset, PeruThe pygmy marmoset is the world’s smallest monkey, weighing just a few ounces and small enough to fit in the palm of your hand. Native to the Amazon rainforest, it uses specialized lower teeth to gnaw holes in tree bark, feeding on sap and gum — an unusual diet among primates. Despite its tiny size, it can leap impressively-long distances between branches. Nikon D500 with Nikkor 500mm PF lens, ISO 800, f/5.6 at 1/400th of a second.