What is the difference between the foot of the Chimpanzee (Pan troglodytes), Gorilla (Gorilla gorilla), and Orangutan (Pongo pygmaeus)?
The Chimpanzee, Gorilla, and Orangutan are primates with five digits on each foot (five toes) with keratin toe nails. Humans also have five digits on each foot with keratin toe nails.
The Gorilla has shorter, wider digits than the Chimpanzee and Orangutan.
The Chimpanzee, Gorilla, and Orangutan have prehensile (grasping) feet. Humans do not have prehensile feet (their feet cannot easily grasp objects).

The Chimpanzee, Gorilla, and Orangutan have two opposable big toes. Humans do not have opposable big toes.
Opposable big toes can move independently and freely, with a rotating movement that is extremely dexterous (skilled and nimble).
The Chimpanzee, Gorilla, and Orangutan have sensitive pads on the bottom of their toes. Humans also have sensitive pads on the bottom of their toes.
The Chimpanzee, Gorilla, and Orangutan have toe prints. Humans also have toe prints.
The Chimpanzee, Gorilla, and Orangutan have lines or creases on the soles of their feet. Humans have fewer lines or creases on the soles of their feet than the Chimpanzee, Gorilla, and Orangutan.
The Chimpanzee, Gorilla, and Orangutan walk flat-footed on their two back feet. Humans also walk flat-footed on their two feet. This is called plantigrade walking.
(Note: The Chimpanzee, Gorilla, and Orangutan are apes, not monkeys. Apes do not have a tail, whereas monkeys have a tail.)




[Location of photographs: Paris Jardin du Plantes Zoo, France; and Uganda Wildlife Conservation Education Centre in Entebbe]
Photographer: Martina Nicolls
Martina Nicolls: SIMILAR BUT DIFFERENT IN THE ANIMAL KINGDOM