1 Humans are not the only species with an opposable thumb. Other animals with opposable thumbs include gorillas, chimpanzees and orangutans. Certain frogs, koalas, pandas, possums and opossums, and many birds have an opposable digit of some sort. So, what makes human hands unique? 1. Humans opposable thumb is longer than any other primate thumb. 2. A long thumb and its ability to easily touch the other fingers allow humans to firmly grasp and manipulate objects of many different shapes. 3. The human hand uniqueness is overrated compared to other animals with opposable digits. 15