While the human brain is the most advanced of any mammal,
our bodies are less than properly designed for the daily wear-and-tear they
experience.
1.
An unsound spine
When our ancestors walked on all fours, their spines arched,
like a bow and like a dog's. The single bow curve allows the spine to withstand
the weight of suspended organs and reduces pressure on the lower vertebrae. But
then we had to stand up and walk on two legs (AKA bipedalism). The spine was
forced to become a column with a curve at the lower back and, to stay balanced,
a curve in the upper spine in the opposite direction. This puts tremendous
pressure on the lower back causing lower back pain. Image Credit
2.
An inflexible knee
The knee is a very complex joint between two huge levers -
the femur and the tibia. While this is really all we need to walk, it does lead
to some serious injuries, which is why every major sport makes it illegal to
hit an opponent's knee from the side.
3.
Crowded teeth
While teeth in general are pretty critical to humans, we
don't need as many molars as we grow. Humans typically have three molars on
each side of the upper and lower jaw. When our brains expanded in size, the jaw
grew wider and shorter, crowding out the back molars. These wisdom teeth, so
named because they appear later in adulthood when you're "wise", may have been
useful before we learned to cook, now they are mostly just a nuisance that need
to be removed.
4.
A backward retina
The design of the retina forces light to travel the length
of each cell, as well as through blood and tissue, to reach the equivalent of a
receiver on the cell's backside. Because of this, the retina can detach from
its supporting tissue causing blindness. It also created a blind spot where
cell fibers converge at the optic nerve - making the brain refill the hole. Fun
fact - the octopus has a flipped retina.
5.
Meandering arteries
We've all hit the ironically named funny bone. The awful
tingling sensation is the result of a human design flaw. The blood flow into
each of our arms and legs from one main artery, which enters the limb on the
front sides of the body by the biceps or hip flexors. The supply blood tissue
at the limb's back side the artery branches out, bundling itself with nerves.
At the elbow, an artery branch meets up with the ulnar nerve, which animates
your little finger and is very close to the skin. That's why when it's it your
arm goes numb or "funny."
The list was adapted from a list
of 10 human design flaws!
Do you have any experience with the design flaws
listed? Any ideas for redesign?
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Re: Five Design Flaws in Humans
