The “design mistakes” that nature has made in the human body

Sigmund Freud said that two scientific findings have profoundly affected human psychology: that the Earth is not the center of the universe and that we have only been on the surface of the planet for a very short time since its formation, 4.5 billion years past. of years.

Everything existed without us.

But one more bump needs to be added: we are not perfect, our species is far from well “designed”.

The male reproductive system is an evolutionary hoax.

The male reproductive system is a clear example of how poorly designed we are. It doesn’t seem very smart or optimal to have one so sensitive organ completely exposed. It would be much better to protect it well, such as the lungs or the heart.

The problem is that our male gametes, the spermatozoa, do not develop properly at our body temperature (36.5ºC), and the solution to lower that temperature a bit is the one we all know.

Other organisms, which are not warm-blooded, such as frogs, have well-guarded and protected male reproductive organs.

They are even safe in some warm-blooded organisms, such as elephants, without harming the male gametes.

backache

The spine is undoubtedly another example of how poorly designed we are. Who has not had one or more back problems in their life?

In the rest of the mammals that walk on all fours, the vertebrae are arranged horizontally, forming an arch that efficiently supports the rest of the structures of the animal’s body.

However, in humans our bipedal condition it literally causes our vertebrae to form a column in a vertical arrangement.

This arrangement makes the lower vertebrae have a great weight to bear and different forces. And it’s why lumbar problems are the rule in our species, not the exception.

A blind spot in the eyes

The human eye is also an example of evolutionary mess.

The retina is covered with photoreceptors that receive light information that the optic nerve then sends to our brain.

The problem is that at the point where the optic nerve crosses the retina no photoreceptorsmeaning we all have a blind spot in each eye.

This does not occur in other species with eyes similar to ours, such as octopuses.

In octopus eyes, the optic nerve fibers lie behind the retina, so they don’t have to pass through it at any point on their way to the brain, and octopuses, unlike us, do not have a blind spot.

throat and choking

Another notorious example of poor body design is that of the human throat. One of the first causes of unnatural death of healthy humans in our species is suffocation.

Last year in Spain, twice as many people died from choking than from car accidents.

The tubes that carry food and air mixing in a very dangerous way in some points of our organism, and the pharynx is the most critical point.

Normally, water and food go from the outside to the esophagus, and air to the trachea. But sometimes things go wrong and food enters the trachea, blocking airflow, which can lead to fatal consequences, such as death from suffocation.

For example, we are not well designed to eat grapes at high speed.

The Magellan Expedition and Vitamin C

Of the approximately 250 sailors who set out with Magellan and Elcano, only 18 completed the circumnavigation of the Earth more than 500 years ago. One of the major problems during the journey was scurvy, a disease that occurs after long periods of eating without fresh food.

Not taking vitamin C causes levels to drop and we are unable to synthesize a protein, collagen, which is essential to maintain and regenerate many of our tissues.

Our organism has vitamin C synthesis pathway, but it is incomplete. That explains why we cannot produce it and we have to consume it in fresh food.

Something that doesn’t happen to cats, they are able to produce their own vitamin C, so they never suffer from scurvy.

Evolution and not intelligent design

These are just a few examples of unintelligent design in our bodies, but the list is long: the birth channelthe multitude of bones in feet relatively inflexible, the mechanism of blood clottingthe nanny’s elbow, the human genome, etc.

We can very well explain our species as the result of evolutionary processes that are far from intelligent design. The same forces have been at work in Homo sapiens as in any other species that has existed or existed: natural selection, genetic drift, hybridization, etc.

We are the result of non-deterministic processes that happened, but could not have happened. And it is felt, but we have no relevant role in the evolutionary process. On the contrary, we are, like so many other species, fruit of chance

*Marcial Escudero is Associate Professor of the Department of Plant Biology and Ecology, University of Seville, Spain.

*This article was published on The Conversation and reproduced here under the Creative Commons license. Click here to read the original version.