9 unnecessary body parts humans no longer need

9 unnecessary body parts humans no longer need

The Useless Body Parts That Persisted in Humans Despite Evolution

human body parts

Have you ever wondered why certain body parts seem completely useless? Well, it turns out that through millions of years of evolution, our bodies have accumulated some remnants of the past that no longer serve a purpose. These “evolutionary leftovers” are fascinating and offer insights into our evolutionary history. Let’s take a closer look at nine body parts that have persisted in humans despite having little to no function.

1. Wisdom Teeth

wisdom teeth

One of the most common examples of a useless body part is our wisdom teeth. These are the third set of molars that typically emerge between the ages of 17 and 25, long after the rest of our adult teeth have erupted. However, due to changes in diet and dental care over time, our jaw size has reduced, leaving little space for these extra teeth. As a result, wisdom teeth often become impacted or don’t fully erupt, causing pain and discomfort.

2. Tailbone (Coccyx)


Did you know that humans have remnants of a tail bone? The coccyx is a small triangular bone located at the bottom of the spine. While it was once used by our primate ancestors to help with balance and mobility, it now serves no real function in humans. In fact, the coccyx can be a source of pain and discomfort, especially if it gets injured.

3. Goose Bumps (Piloerection)

goose bumps

Have you ever experienced goose bumps? Those tiny raised bumps on your skin are a physiological response called piloerection. In our distant ancestors, the ability to raise body hair helped them stay warm or appear larger when threatened. However, humans have lost most of their body hair, so this response is no longer useful. Nowadays, goose bumps are often triggered by emotional or sensory stimuli, but their practical purpose has faded away.

These are just a few examples of the many evolutionary leftovers found in the human body. But why do these useless body parts persist? To understand this, we need to delve into the concept of evolution.

Evolutionary Leftovers and Why They Persist

According to Dorsa Amir, a developmental psychologist at Boston College, some traits may become obsolete but still remain benign to humans. It means that they don’t cause harm or significantly affect our quality of life, so they continue to coexist with our other functional body parts. These remnants persist simply because they are not detrimental enough to be completely eliminated through natural selection.

Other Examples of Useless Body Parts

Let’s take a look at a few more examples of body parts that have stuck around despite their lack of function:

  • Gastrointestinal Caecum: This part of the intestine, once responsible for digesting cellulose in our herbivorous ancestors, is now a mere vestige in our bodies.
  • Vomeronasal Organ: Once used for detecting pheromones in animals, this small sensory organ in the nose is now non-functional in humans.
  • Palmar Grasp Reflex: During infancy, babies instinctively grip objects placed in their palms, a reflex inherited from our primate ancestors. However, this reflex disappears as we grow older.
  • Body Hair: While we still have some hair on our bodies, it is much less significant than in our distant relatives. Humans evolved to lose body hair for various reasons, including temperature regulation and reducing the risk of parasites.

Understanding Our Evolutionary Heritage

Although these body parts may no longer serve a practical purpose in modern humans, they offer valuable insights into our evolutionary history. By studying these “evolutionary leftovers,” scientists can unravel the mysteries of our ancestors and better understand the forces that shaped us into who we are today.

So, the next time you marvel at the peculiar quirks of the human body, remember that there is often a fascinating evolutionary story behind them. These relics of the past remind us of the incredible journey our species has taken, constantly adapting and evolving throughout the ages.