5. Baby Marmoset vs. Human Hand
Found In: Eastern South America.
Price: Not specified
There are smaller kinds of monkeys on the spectrum that are more popularly referred to as marmoset monkeys, even though other species of monkeys can reach enormous sizes. You can see how small a marmoset is at birth from this picture.
Baby Marmoset vs. Human Hand
Due to their physical similarities to humans, marmosets are very frequently used as test subjects in medical research. Furthermore, marmosets are unique among primates in that they are able to give birth to non-identical twins.