Apes

African apes are easily distinguished from the monkeys that inhabit the continent. All three species of apes are large-bodied, ranging from the approximately 90 pound chimp to the 400+ pound gorilla.  And when we say 400+, that’s pretty much solid muscle, not adipose tissue!  In addition to large body size, the distinguishing features of the African apes are their large brain to body size, their particular tooth structure, wide faces, and lack of a tail.

Gorillas (Gorilla gorilla) have been called the gentle giants of the primate world, because their large size is actually maintained by a vegetarian diet, with lots of fruits and veggies and an occasional termite or caterpillar, but no red meat. Their huge bellies house a massive digestive tract that is necessary to break down all the roughage that passes through each day.  Did you know that an adult male gorilla can consume over 40 pounds of greens a day?! Much of that food, particularly the leaf matter, passes through the digestive tract without being completely digested.  So, this naturally leads to a quick discussion of coprophagy.

Coprophagy is defined as the eating of stool, or feces.  While it probably seems pretty revolting to you, quite a few vegetarian mammals do this. By digesting the same material twice, the animal is able to get more energy out of the initial food matter they consumed without having to travel to find a new food source. Some animals regurgitate and re-chew and some pass it from the other end and re-chew.  Same concept going on at either end. So, yes, gorillas do eat their poo from time to time, but that doesn’t make them gross or nasty.  It just makes them super fuel efficient!

Gorillas tend to live in small groups (about 10-20) made up of adult females and offspring with typically one silverback male, who defends the group from predators and take-overs by other males. While gorillas are good climbers, they spend a good amount of time on the ground, knuckle walking on their 3rd and 4th knuckles to support their heavy bodies.

Another species of African apes, the common chimpanzee (Pan troglodytes), can be found across diverse habitats throughout much of central Africa. Being smaller in body size than gorillas, chimpanzees tend to spend quite a bit of time in trees, being expert climbers that can maneuver up tree trunks with amazing dexterity.  When traveling on ground, chimpanzees knuckle walk and also walk upright on two legs (bipedal locomotion) quite frequently. Watching chimps engaged in upright posture brings up quite obvious similarities between chimpanzees and ourselves. In fact, we share much more in common than bipedalism, being that chimps are extremely intelligent and highly sociable, even political animals capable of cooperative war. Our similarities come from our DNA, the chemical code that determines which proteins our cells will produce to ultimately form our brains and bodies. The DNA structure of chimpanzees is almost 99% identical to human DNA, meaning that our differences in intellect and physical appearance lie in the less than 2% difference in our DNA code.  Scientists are currently trying to understand how these genetic differences ultimately become responsible for the differences we see between organisms, but in the meantime, primatologists continue to marvel at the human-like traits and behaviors evident in chimpanzees.

Commonly confused for chimpanzees, bonobos (Pan paniscus) earned their own unique species name in 1993.  Despite many similarities to chimpanzees, bonobos look and act somewhat differently. Physically, bonobos are the supermodels of the ape world, showcasing lean, sinewy bodies with long legs and narrow chests.  Bonobos look different than chimps due to their darker facial skin and slicked down hairdos with a center part (think Alfalfa sans cowlick). And whereas all males are dominant to females in chimpanzee society, bonobo females regulate the group’s access to the best food and form alliances with each other against males that get out of line.  Now, before we get to feeling too sorry for those poor hen-pecked males, it might be useful to note here that male bonobos mate much more frequently than do male chimpanzees. So, in this case, letting the females rule the roost definitely has its advantages, from the male point of view.