Exercise and Health- Why are we naked? And how big are our penises?

I remember being struck by a national geographic programme that I watched years ago. It started with a huge sumo wrestler weighing 150 kilograms boasting on camera about his invincible strength. The idea was to have a tug-of-war between him and a tame orang-utan. The animal was only one third of the man’s size. A moat filled with muddy water separated the participants. The contest started with much fanfare, further boasts and confident assertions by the wrestler. Two tugs and three seconds later the man plunged into the mud with a tsunamifying splash. He was not available for comment later. The ape showed its glee by jumping up and down and clapping the hands. But the winner modestly declined to say much.

Man is a puny animal, when compared to others of similar or even much smaller size. But the increased strength doesn’t necessarily help them.  Note that it is the orang-utan that is endangered, while the planet is overrun with human beings. The conventional wisdom is that we survive only by our superior and collective brains, weaving strategies and executing them by pure thought.

But there is one purely physical feat that we can do much better than most other mammals. No- I am not talking of manual dexterity or ability to make tools. That is due to our brain power and designed hands.

Can you outrun an antelope galloping across the African savannah? No? What about a hare? Still negative about your abilities? A chicken? I can attest from personal experience that outrunning a chicken is possible for an average person. Initially, the terrified chicken runs much faster and you are about to give up. Many people do. That is the mistake. You keep chasing at a comfortable pace. After a few minutes, it just stops from exhaustion. You can just pick it up.

Apparently, it may be so with most animals, if you are properly trained. There are tribes in central Africa and the Kalahari that routinely runs down large prey like deer through a combination of endurance running, tracking skills, and sheer persistence. The hunt is deliberately done in the midday under the blistering hot African sun. Some people theorise that this may have been one important way by which early humans obtained their food. No animal, however well-trained can run for hours and hours, like a marathon runner.

We may argue that only a trained human can do it. Let me ask you, can a trained human match a gorilla or a chimpanzee in a wrestling match? It is not possible. Endurance is natural to us.

How can we be sure? The scientists say we have a lot of clues in our own bodies. Comparative anatomy, they say, can teach us a lot about evolution.

Look at the testes, for example. What I mean is, consider them, for a moment. The great Apes are our closest relatives, evolutionarily. Primates, including monkeys are our extended family. Which primate has the largest testes?

If you thought that it is the massive gorilla, you are wrong. It is the chimpanzee. The chimpanzees are the most sexually promiscuous of all the primates. Almost the entire male members of the group will mate with a receptive female in heat. The gigantic testes are to produce copious amounts of sperm, as they compete with those of other males, in the female’s genital tract.

And who gets the prize for the biggest penis? If you answered chimpanzee, you are dead wrong. It is the human male. The reasons we will come to later.

Ever wondered why we walk on two legs? Again, the main reason is supposed to be that it freed our hands to make tools, thereby driving our superb brain growth. But the Australopithecus were the first humanoids to walk upright, and their brains were only as large as those of the apes today.

The answer appears to be much more complex. On analysis, it appears that running on two legs is much more efficient than doing the same on four legs. One important reason is that the front legs in an animal are connected to the chest cavity that bears part of the load. As you run more, you pant. The running interferes with the panting. In the human our legs are free to run, while our chests are free to pant, independent of each other. What is needed is a superior sense of balance to manage the inherent instability of the bipedal gait.

Another question is why we are naked. That is, comparatively hairless. That is an important difference from all other mammals, except the whales and dolphins. The aquatic mammals need their smooth bodies to reduce drag. There are some who argue that we had a seaside existence in our history that promoted this, but this idea is not bought by most experts. One very likely reason is better heat management while running long distances in the oven-hot African plains.

This also explains our sweating ability. Most medium mammals of our comparative size cool down by panting. The saliva evaporates and the heat dissipated through the breath. This is much more inefficient than sweating. And we are designed to sweat copiously. The only problem is that there has to be a wind for this to be optimal. A runner generates his own wind.

If these conjectures are correct, then our sedentary existences may be shockingly out of sync with our bodies. It is likely that there is more than a grain of truth to this theory.

Are you still wondering why we have the largest penis among the primates? If you have a convincing answer, tell me. Or tell the experts. Better still publish it, for you may become famous. Nobody knows the answer yet. (You can read more from the book- Health and Happiness without Bullshit)

Dr Jimmy

I am a Doctor, Writer and Science Communicator. I am a member of Info- Clinic, and have written a few books. This site features my blog posts and stories. Thank you for visiting. ഞാൻ എഴുതാൻ ഇഷ്ടമുള്ള ഉള്ള ഒരു ഡോക്ടർ ആണ് . നിങ്ങളുടെ താത്പര്യത്തിന് നന്ദി .