…BUT HUMANS HAVE TO RUN
When we look at anthropoid apes, we recognize ourselves: Our appearance, behavior , and phylogenetic history have a lot in common . In fact , humans and chimpanzees share 98 . 8% of their DNA . And yet there is one characteristic in which we are very different . Spoiler alert: It ’s not the ability to think…
Get up with the sun and set out to find a yummy breakfast of sweet fruit. Then a short nap and a bit of mutual grooming punctuated by snacks followed by an outing to find new food sources. Next, a welldeserved siesta followed by another meal of sweet ripe fruit. A nap before dinner, and then it’s time to climb high up in a tree and build a new nest with a soft mattress of leaves and twigs. And so another fine day in the life of a chimpanzee draws to a close.
ARE CHIMPS STRONGER THAN A POWER ATHLETE?
Chimpanzees spend up to 20 hours a day resting, sleeping, and eating— it’s a schedule that’s more or less the same among all the anthropoid apes, from chimps to orangutans to gorillas. They all seem quite pleased with this lifestyle, but a human who adopts it could expect the result to be obesity at best. According to a CDC study of U.S. mortality data, more than 8% of American deaths can be attributed to lack of exercise, and in the 40–65 age group the figure is almost 10%. The World Health Organization has estimated between 60 and 85% of the global population does not get enough exercise and 2 million deaths every year are attributed to physical inactivity. So do the anthropoid apes enjoy better lives than we do, then? “Survival of the fittest” has been the mantra of evolutionary biologists ever since Charles Darwin published his seminal work On the Origin of Species by Means of Natural Selection in 1859. But what do chimpanzees care about
the theories of a deceased British naturalist? They do just fine on a highcalorie diet and very little exercise. Humans? Not so much.
But that’s not all: Though chimps never lift a finger unless they have to, Arnold Schwarzenegger in his prime could not have defeated a 130-pound chimpanzee at arm wrestling. Even renowned runner Usain Bolt’s record of 100 meters in 9.58 seconds is not too much faster than a chimp’s speed. “So even though male chimpanzees weigh less than a typical human adult, they can produce much greater force and sprint faster and are obviously more agile during their locomotion,” says Harvard University evolutionary biologist Daniel Lieberman.
All of the combined daily activities of a chimpanzee amount to less than 2 miles of walking, a distance that a human being can cover in little more than half an hour. But chimps also like to climb, sometimes more than 300 feet in a day, so their total daily exercise is actually the equivalent of 4,000 to 5,000 human steps, which is still more than the average American gets. One generally accepted rule of thumb for getting enough exercise is to walk 10,000 steps daily, however Lieberman says this is an arbitrary figure that actually originated as an advertising slogan in Japan. Getting enough exercise definitely does lower the risk of developing such “modern” illnesses as heart disease, diabetes, and cancer, and the UK’S Alzheimer’s Society says getting regular exercise also “appears to be one of the best things you can do to reduce your risk of dementia.”
Despite our common heritage and the fact that we share 98.8% of our DNA with the chimpanzees, a lot has changed over the past 2 million years of human development. What sets us apart today is more than just our erect gait and the fact that the human brain is almost three times bigger than that of a chimp. To understand the differences we have to examine the origins of humankind…
CAN A MAN OUTRUN A HORSE?
The scene: somewhere in Southern Africa. The sun is blazing and the air is hot, considerably hotter than 90°F. In the open grassland a group of early humans armed with primitive spears is hunting a herd of cape buffalo. The herd is large and the bovine animals are strong, fast, and very dangerous. Nonetheless they avoid contact with the humans who are pursuing them, using hoof prints to track the animals whenever they are no longer in sight. In this confrontation with one of the continent’s most menacing beasts, the hunters have a clear advantage: Humans can run—and keep running for a long time.
Most mammals have to pant to get rid of their body heat, and that is not an inefficient form of cooling. Panting is not helpful, for instance, when an animal is trying to breathe deeply to get as much oxygen as possible. But just as modern humans are today, prehistoric humans were equipped with several million sweat glands to help them cool off, and fortunately they’d long since lost the furry hides that would have retained heat and moisture. And while running on two legs is generally slower than running on all fours, it requires less energy. Thus early humans were equipped to run for many miles, even in the heat. And these human advantages would prove deadly to at least one animal in the buffalo herd: After a relatively brief pursuit, the first of the massive creatures would simply drop dead from sheer heat and exhaustion, and the hunters would prepare for a feast.
Chimpanzees weigh less than a human adult but are much stronger and more agile.”
DANIEL LIEBERMAN, evolutionary biologist, Harvard University