In The Descent of Man (1890) written by Charles Darwin, he explains that there are many structures of the human body that no longer served a purpose for day to day survival. These once useful structures are now called vestigial structures.
To this day, many of these vestigial structures continue to blow minds because of their irrefutable truth. So here are 5 vestigial structures of the human body that you may not be aware of.
Get ready for that “oh gosh no” moment… for once it is pointed out, it is blatantly obvious.
1) Semilunar Fold
The plica semilunaris is a small fold of tissue on the inside corner of the eye. It is a remnant of the nictitating membrane. This nictitating membrane is the “third eyelid” seen in many reptiles, amphibians, and fish. This was thought to be useful in protecting the eye and allowing for humans to hunt for fish under water with very little discomfort.
2) Ear Muscles
We all have that one uncle that can wiggle his ears… but what is the purpose of those ear muscles that allow that to be achieved? It is thought that those muscles worked to position the ear to receive a better reception of incoming sounds in the wild. This was very important for navigating through the night hours. This trait can be seen in dogs and other animals with heightened auditory systems.
3) Wisdom Teeth
As you get older, all your friends seem to be getting their wisdom teeth removed, but why? Back when homo sapiens were in their more primitive stages, wisdom teeth were a necessary tool for thoroughly grinding hearty leaves and other botanical structures. Now, they simply serve no purpose due to modern technological advances. Additionally, genetics have been trending to produces smaller offspring versus larger ones. This means there is simply not enough room for the wisdom teeth in the jaw, which henceforth causes more problems than what they’re worth.
4) Arm Hair
Due to modern fashion trends, many people shave their arm hair off. In doing so, there is no apparent differences between having and not having arm hair. That is because there is no difference, at least not anymore. Arm hairs went hand-and-hand with the involuntary response to coldness, goose bumps. Anatomically, goose bumps are simply the follicle in which the hair rests in contracting to tighten around the hair. This would then cause the hairs to stick up. What this does is help retain body heat under this small coating, hence why it is a response to coldness. This same process is seen in birds when they fluff their feathers to retain more heat.
5) Appendix
The appendix was previously used to fully digest cellulose and other indigestible plant materials. Additionally, some research suggests that the appendix may guard against the loss of symbiotic bacteria that aid in digestion. Intestinal bacterial populations entrenched in the appendix may support quick re-establishment of the flora of the large intestine after an illness, poisoning, or after an antibiotic treatment depletes or otherwise causes harmful changes to the bacterial population of the colon. The appendix sounds important, right? So how can we get it removed? Due to modern medicine protecting us from all the above, the appendix is therefore not a necessity.
So on a scale of 1-10 how mind blown are you right now, eh?
