6 Bitting the inside of one’s own mouth.

All of us at some point in our lives have bitten the insides of our cheeks. It’s one of the worst injuries you can imagine. It’s quite frustrating as it takes forever to heal and keeps getting irritated by certain foods, especially citrus ones. Unlike an external wound, there is not an option to cover it up with a bandage. And if gets re-bitten, then that’s another story.

Accidental cheek biting is not a cause for concern. It mostly happens because the person was distracted while chewing food. Talking is the biggest culprit followed by watching TV, reading, or doing any other activity. But since our mouth is filled with sharp teeth, it would have been appropriate if the inside cheeks had some kind of protection from being bitten. This feature is a simple missing element in the complex design of the human body. (source)

7 Our pelvis is extremely small and leads to a lot of complications when it comes to childbirth.

Childbirth is tough. And adding to the complications is the human pelvis. The pelvis in the female human body is an example of how evolution led to an imperfect mammalian design. There are two problems when it comes to the female pelvis. The first is that since we humans are bipedal, the birth canal is slightly tilted. The baby does not come out through a cylinder-like-canal. Instead, it has to take the sharp curve of the pelvis. This makes human births more complicated than other mammals.

The next problem is the size of our head. On account of evolution, humans have received the gift of large brains. As a result, the head size is also larger as compared to other mammals. Now human babies, having huge heads as compared to other mammals, add further complications to the already existing problem of the tilted pelvis. (1, 2)

8 The laryngeal nerve needs only travel a few inches from the brain to the larynx but goes the long way around under the aortic arch instead.

The laryngeal nerve is the nerve that connects to the larynx. The nerve takes a long route to get to the larynx. Because of this, it is often called “one of the most striking cases against intelligent design.” The nerve starts from the brain and goes deep into the chest cavity, and finally up to the larynx.

Biologists have been trying to explain this bizarre design flaw for a long time. Some suggest that it is due to embryological development. This is true to a large extent but still does not explain why the nerve starts on the wrong side of the aortic arch. If at the first stage of embryonic development the nerve would start correctly, then this problem would not even exist. So, unless and until scientists are able to pinpoint the advantage of the detour by the nerve, it’s going to remain a design flaw of the human body. (source)

9 Human spines are so inefficient that 80% of people suffer from neck or back pain at some point in their lives. 

Our spines are a complete mess. Bruce Latimer, director of the Center for Human Origins at Case Western Reserve University, says, “It’s a wonder we can even walk!” Our ancestors used to walk on all fours, like other animals. At that time, the spine used to be arched, like a bow. The shape was perfect to withstand the weight and pressure of the dangling organs. But then evolution kicked in and we started walking standing up. The entire spine had to rotate by 90 degrees! The arched spine was forced to behave like a column.

Now, to enable humans to walk on just two legs, the spine underwent few more changes. It curved forward at the lower back. At the same time to balance the head, the upper spine curved in the opposite direction. Because of the change in the design, there’s a lot of pressure on the lower vertebrae. This has led to almost 80% of the adults suffering from lower back pain.

It’s like forcing a suspension bridge to act like a pillar. There’s bound to be problems. (source)

10 Humans are the least efficient thermoregulators in the mammal world.

We sweat to maintain our body temperature. This is a common trait among mammals. But we humans have too many sweat glands when compared with other mammals. This makes us one of the least efficient thermoregulators in the mammal world. Moreover, with so many sweat glands, we lose a large quantity of water by doing simple things like walking or exercising. Even being nervous or stressed out leads to loss of water in humans! This would have been a problem if we were still living like animals.

But even though this is a terrible design, it makes sense when evolution is taken into account. We sweat like apes, our evolutionary cousins! (1, 2)