Our bodies are like museums of evolution. We walk on two legs because a common ancestor evolved to do this millions of years ago. And, like every showroom, we house organs and functions that have survived their original goal.
Take the attachment for example. Once a heavyweight Digest a plant -heavy dietIt was rejected by evolutionary scientist Charles Darwin, who wrongly decided that it was no longer necessary because of nutritional shifts. Wisdom teeth helped early people gnawing by raw carrots and cool meatBut today they are little more than an expensive dental complication, because our food is processed more. Even goosebumps– Without a handy way to pick body hair for heat or protect against predators – are now seen as little more than a fleeting moment of aesthetic drama.
So why do most of us still have these body parts and functions?
It is probably because they do not harm us, explained Matthew Ravosa, the director of the Center for Functional Anatomy and Evolution at Johns Hopkins University School of Medicine. Although they may not benefit, the lack of disadvantage reduces the natural selection pressure that usually eliminates properties within a population.
Some of these functions have been cooperated or reused for another function due to evolutionary changes in the environment, behavior or selective pressure. “The attachment is a good example of that,” Ravosa added.
[ Related: Could we ever regrow our adult teeth? ]
Once considered a remnant, the attachment can play an essential role in intestinal health, allowing the immune system to fight pathogens. It contains A high concentration of immune tissue And houses useful bacteria that re -populate intestinal microbiome after an illness or antibiotics. This concept has challenged the long -term conviction that the appendix is a superfluous body.
“Sometimes redundancy has a way to appear under certain conditions; They are not really superfluous, “said Michael Snyder, director of the Snyder Lab at Stanford University. “Going back to the appendix, it has been suggested that it has a use.”
It is not well understood what is there Real Overview and which body parts can still function, albeit in a different way. Yet we start seeing people born without some body parts that are usually useless. Studies have shown that around 35 percent From the population are now born without wisdom teeth. (Fortunately!) The Palmaris Longus, a tendon in the forearm present in some but absent in others, once helped with climbing and moving but is now functionally irrelevant. Research has shown that A small percentage of the population Is even born without – and not having the muscle has no influence on the grip strength in no significant way.
[ Related: Why do humans have toenails? Because we’re evolutionary ‘weirdos.’ ]
Since evolution is underway, can we be about to throw more parts as our diets, medical interventions and technology progress?
As is often the case with future -oriented scientific questions, the answer is that nobody really knows.
“There are no indications that we have any idea about what the future has in store for us, because the pace at which the technology changes and that evolution can influence is so great, and it is much less predictable than one thinks,” ” Explained Ravosa.
“We largely learn about remains by looking by looking back,” he added. “We will just have to sit and see because we cannot predict the future.”
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