Have you ever wondered why you get wrinkled fingertips if you are in the water for long periods of time?

It’s actually a neat evolutionary quirk, developed over time, designed to enable us to survive. So how does it work? Why do our fingertips get wrinkled when in water? Not only that, but why is it only our fingertips and not other parts of our body that wrinkle?

Why do we get wrinkled fingertips in water?

Imagine the treads on a racing car’s tyres. In dry weather, drivers use smooth treads because these will have a better grip on the road. However, on a wet track, drivers will change their tyres and opt for ones with deep treads.

The treads in these tyres channel water away from the surface area which allows the tyres to grip the road more efficiently. The same is true when the skin on our fingertips gets wrinkled. If we have been in the water for a long time, we need ‘treads’ in our fingertips to be able to grip a slippery surface in order to be able to escape.

So, is this a reflex action or is something more sophisticated going on? Actually, there are specific nerves in our fingertips. These nerves send messages to the brain after a certain time in the water. Our brain then sends back messages to the surface of our skin and this accounts for our wrinkled fingertips.

4 More Evolutionary Quirks

  1. The Life or Death reason for sighing

Have you ever felt so exasperated at a situation that you’ve sighed heavily? You might just have saved your own life. Sighing isn’t just about releasing tension or pent-up frustration. It is crucial to maintaining lung function.

Our lungs are made up of tiny balloon-like air sacs called alveoli. These alveoli inflate and deflate every time we take a breath. Oxygen enters the alveoli and carbon dioxide leaves via the bloodstream. However, every so often individual alveoli collapse.

“When alveoli collapse, they compromise the ability of the lung to exchange oxygen and carbon dioxide,” Jack Feldman said. “The only way to pop them open again is to sigh, which brings in twice the volume of a normal breath. If you don’t sigh, your lungs will fail over time.”

A sigh is an involuntary deep breath that expands these collapsed alveoli and pumps them back up to full capacity again. Without this built-in mechanism, these tiny air sacs would gradually collapse leading to lung failure.

  1. Shaking your head means I’m full up

Body language is a fascinating area of study. For example, why do we shake our head to say no and nod to say yes? Well, scientists have the answer to one of these questions. And, when you think about it, it makes perfect sense.

Despite the shake of the head indicating one of human’s most recognised gestures, no one really knew its origins. Until now. The key is to look at babies. When babies are full up, they don’t have the necessary language skills to express that they don’t want any more food.

Babies turn their heads from side to side to avoid the next mouthful of food they do not want. This rejection of food at an early age has come to signify ‘no’ in all other aspects of our adult lives.

  1. Why we stick our tongues out when we concentrate

You often see children so intently focused on a task that they stick their tongues out. But why does it help with their concentration? It makes more sense if we think about what the tongue is responsible for.

It has thousands of taste buds that work to identify millions of combinations of flavours. More importantly, however, it is always moving around the mouth, keeping us from choking and helping to swallow the build-up of saliva.

The tongue is also responsible for formulating language. It is a huge muscle that changes shape to form the sounds of letters and as such, is connected to the brain’s language centre.

This means it is constantly sending huge streams of information to many different areas of the brain simultaneously. By sticking it out and holding it in place by biting it, we are restricting its movement.

By keeping it still for a moment, we are able to calm this constant stream and free up our brains to focus on just one activity at a time.

  1. Your speech reflects your environment

Can our environment have an effect on the way we speak? According to one theory, it can. The ‘acoustic adaptation’ speculates that the region you were raised in has a direct effect on your speech. And it is all to do with how sound travels and how we hear it.

For example, take forest dwellers. Sound behaves differently in a forest compared to a vast desert. Consonants tend to get lost in a dense forest so you only hear the vowels.

In hotter areas, pockets of hot air distort hard consonants. So languages evolve differently in hot and cold climates. Warmer climates tend to have softer vowels and use a lot of open syllables. Just think of Hawaii and ‘aloha’.

Whereas in more temperature climates, such as Germany, they hear fewer vowel sounds and, therefore, use harsher consonants for the endings of their words. For instance, ‘how are you?’ translates into German as ‘Wie geht es dir?‘

Wrinkled fingertips are just one evolutionary quirk humans have developed over the years. It just goes to show the incredible way our bodies adapt to master our environment.

References:

  1. http://www.bbc.com/
  2. https://www.npr.org/

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