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Humans are the only species with chins. Here are the wildest theories at to why.

Chinteresting, indeed.

Photo credit: Canva, Gage Skidmore/Wikipedia

The chins evolved to bring us Henry Cavill. Duh.

When we talk about what makes humans special, we usually point to our big brains, our opposable thumbs, our affinity for tool-making…or, more recently, the fact that we can turn oat milk into a personality trait.

But scientists say there’s something else that sets us apart from every other species on Earth. Something so ordinary you probably don’t even think about it when you look in the mirror.

It’s your chin. Yes, really. That tiny little nub of bone under your smile is one of the weirdest, most mysterious features in all of evolution.

No other animal has one. Not chimpanzees. Not gorillas. Not even our closest ancient relatives, the Neanderthals. Somewhere along the evolutionary line, humans woke up with a chin. Researchers have been trying to figure out why ever since, which has led to some pretty wild theories.

evolution, chin implants, cool history, science, pbs pbs eons, paleontology, smithsonian magazine Neanderthal media1.giphy.com

Chewing, by far, is the prevailing and most studied theory. After all, our ancestors’ jaws and teeth got smaller as our diets changed, and perhaps the chin evolved to help keep everything strong and supported. Flora Gröning, a biological anthropologist at the University of York, put that theory to the test by digitally modeling how human and Neanderthal jaws handled pressure. Turns out, she found, the chin does give our jaw a little extra reinforcement while chewing. Score one for Team Chewing.

But another camp believes it’s all about how we talk. In 1913, physician Louis Robison suggested that the chin developed to support the human language growing more complex, acting like a tiny shock absorber to protect our jaws from the muscular gymnastics required for human speech. Because let’s be honest, “She sells seashells by the seashore” is no easy task.

Then there’s a third, more scandalous idea: maybe it’s about attraction. According to the sexual selection theory, our chins could be nature’s version of a dating app filter. Studies have found that women may subconsciously prefer men with broader, more prominent chins, which signal testosterone and “good genes.” Men, on the other hand, often favor women with narrower, softer chins—traits linked to higher estrogen levels.

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This theory was strengthened when researchers Zaneta Thayer and Seth Dobson examined nearly 200 skulls from around the world and noticed that male chins did tend to be taller and more pronounced. That suggests our chins might have been shaped, at least in part, by what our ancestors found attractive.

However, the more outlandish theories involve laundry…and boxing. Some think that chins came about so that we could clamp down on cloth while folding, while others think that they evolved to take a punch.

Still others think chins just sort of happened. No actual purpose, just a byproduct of evolution. Wouldn’t be the first time. (Looking at you, belly buttons)

In the end, there may not be one single reason we have chins. It could be a mix…a little bit of chewing, a little bit of talking, and a little bit of flirting. A little bit of punching? Evolution, it seems, has range.

- YouTube www.youtube.com

So next time you rest your hand under your chin in deep thought, give it some credit. That humble bump of bone may not get the glory our brains do, but it’s uniquely ours. A small, sculpted reminder that being human is as much about mystery as it is about the mind.

Special thanks to Smithsonian Magazine and PBS Eons for supplying such interesting info!

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Sorry, chimps. Oxford professor says octopuses will rule Earth after humans.

They are civilization builders.

via Dan Asaki/Unsplash and Canva/Photos

The last man on earth and a perplexed chimp.

It’s upsetting for many to consider that humans may not be around one day. But it’s not shocking, given the damage that we’ve done to the planet through climate change and the fact that we’re the only species to create a nuclear bomb. Even if we don’t do ourselves in, the odds aren’t in our favor of the Earth not finding a way to eliminate the surface disturbance known as humanity. Studies show that since life began on Earth, 99% of species have ever lived have gone extinct.

So, after the last human on Earth passes away, who will take over the mantle of being the apex predator and build Earth’s next great civilization? University of Oxford professor Tim Coulson has posited that a rather unorthodox species, the octopus, will take over after we’re gone. His new book, The Universal History of Us, outlines his thinking for the cephalopod takeover.

What species will take over the Earth after humans are gone?

octopus, octopus swimming, end of man, evolution, smart animals, survivors, human extinctionA happy octopus swimming.via Canva/Photos


Most people would think that the great apes are our natural successors. Still, Coulson says otherwise. “Hominids such as chimpanzees and bonobos are intelligent animals with opposable thumbs, tool-using abilities, and, at least for short distances, the capacity to walk on two legs, traits shared with us,” Coulson told The European. “Despite these similarities, they would likely face extinction alongside humans, as they are equally exposed to threats in our shared environment.”

Coulson says intelligent birds will fail to take over after humans because they “lack the fine motor skills needed to construct a civilization." However, octopuses have the physical, mental, and social possibilities to build a great society, especially without humans to thwart their efforts.

“Their ability to solve complex problems, communicate with one another in flashes of color, manipulate objects, and even camouflage themselves with stunning precision suggests that, given the right environmental conditions, they could evolve into a civilization-building species following the extinction of humans,” Coulson said. “Their advanced neural structure, decentralized nervous system, and remarkable problem-solving skills make several species of octopus well suited for an unpredictable world.”

octopus, octopus swimming, end of man, evolution, smart animals, survivors, human extinctionA happy octopus swimming.via Canva/Photos

Coulson believes that octopuses could evolve to create a great civilization beneath the sea that rivals the world created by humans. With some help from evolution, they may also learn to adapt to life on land and take over where people left off. This may sound improbable, but 370 to 390 million years ago, the first sea creatures left the ocean to live on dry land. Further, some animals, such as dolphins and whales, started in the ocean, lived on land, and then returned to the sea after disruptions to their habitats. Could a similar disruption cause the octopus to look for a better life on the beach?

Culum Brown, a professor in the School of Natural Sciences at Macquarie University, is skeptical that octopuses have it in them to make the big leap to the top of the evolutionary heap. “Despite all their tricks, octopuses are still working from a snail blueprint, and there’s only so much you can do with that toolbox. They are also highly constrained by their very short life-span,” Brown wrote in The Conversation.



Sydney Philosophy of Science Professor Peter Godfrey-Smith told Popular Mechanics that octopuses are also hindered by their social dynamics and lack of “intergenerational connections.” Given that they have yet to develop them over millions of years of evolution, Godfrey-Smith is doubtful they’ll occur “anytime soon.”

It’s impossible to know what the future holds, but don’t be shocked if, one day, octopuses develop a superior civilization based on peace, love, and seaweed. “Random mutations, unforeseen extinction events, and population bottlenecks can all significantly influence the trajectory of evolution, making it challenging to determine whether another species will develop human-level intelligence or the inclination to construct cities,” Coulson told The European. “But could octopuses replace humans–and potentially also primates–if they were to die out? Absolutely. They could become the brains of the sea.”

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Viral video shows how to find your vestigial organs

Your tailbone was once an anchor for … your tail.

Image from Vox on YouTube.

Evolution of the body is divergent.

The human body is an amazing organism, to say the least.

To watch an athlete dunk a basketball or a ballerina turn a pirouette is to witness an extraordinary machine at work. But the human body is also a biological junkyard of useless ideas it has yet to ditch as we evolve.

There are many organs, tissues, and cells that make up the human body that, though they once had an evolutionary purpose for our survival, are now obsolete. Think about your tonsils or wisdom when they get inflamed to the point of needing surgical removal. These and all other "useless" body parts are known as vestigial organs and every species from humans to birds to felines to fish have them.

The video below goes over just a few of the vestigial organs we can locate on our bodies if we know where to look.

10-15% of people can see a tendon in their wrists that connects to the palmaris longus muscle. Although it serves no purpose for humans, it's essential for primates that live in the treetops and swing from limb to limb.

Humans also have three muscles around their ears that allow some people to make them wiggle. When fully formed in other mammals, the muscles work to rotate the ears in order to pinpoint the source of sounds. Although these body parts are worthless in a practical sense, they serve as a reminder of our vast evolutionary history and reveal our deep connections to other beings on the planet. That knowledge is far from useless.


This article originally appeared eight years ago.

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Study shows that grandmas may feel closer to their grandkids than their own children

There's an important reason for it.

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A grandmother and grandchild.

For the past 55 years, scientists have theorized that a major reason why humans live so much longer past their reproductive years than other species is because of grandmothers. The "grandmother effect," as it's known, postulates that in hunter-gatherer societies, grandmothers played a vital role in finding food and raising children. In fact, the grandmother's role was so important that it had a huge impact on whether or not children survived.

"By relieving a mother of some of her child-raising responsibilities, so the thinking goes, grandmothers make it easier for their daughters to have more children and also make it possible for those children to have longer lives by helping them during the difficult early years of life," Haider J. Warraich writes in Stat. Two studies further this hypothesis by showing the important roles that grandmothers have in the survival of their grandchildren. A study of birth and death records in Finland for individuals born between 1731 and 1890 found that having a maternal grandmother between the ages of 50 and 75 increased a child's survival rate.

Another study found that proximity to grandmother matters, too. The shorter the distance between grandmother and grandchild, the more involved the grandmother can be and the more benefits that accrue to her daughter and grandchildren.

The grandmother effect could be a major reason why a new study shows that grandmothers may feel a closer emotional bond to their grandchildren than their own offspring.

A study by James Rilling of Emory Universityin Atlanta, Georgia published in "The Royal Society" measured brain function in 50 grandmothers with at least one biological grandchild between 3 and 12 years old.

Grandmothers were shown photos of their grandchild, an unknown child, an unknown adult and the same-sex parent of the grandchild. The study found that when a grandmother saw a photo of their grandchild it activated parts of their brain associated with emotional empathy and movement.

When the grandmothers saw a photo of their adult child, it activated areas of the brain associated with cognitive empathy. So, to put it simply, when shown the pictures, the grandmothers were attempting to emotionally empathize with their grandchildren while trying to cognitively understand what their adult children were thinking.

"That suggests that grandmothers are geared toward feeling what their grandchildren are feeling when they interact with them," Rilling said in an Emory news article. "If their grandchild is smiling, they're feeling the child's joy. And if their grandchild is crying, they're feeling the child's pain and distress."

Given the importance of the grandmother effect, it's no surprise that our grandmothers seem to be hardwired to love us in the deepest way possible. Science shows that without this incredible bond, humans may not have made it this far. Conversely, it also shows that without having such an important role in their post-reproductive years, our grandparents may not have evolved to live so long.

In the end, the relationship appears to be symbiotic. Grandmothers promote the survival of a child who one day may grow up to be a grandparent and live longer because they have such an important role in the life of their grandchild.


This article originally appeared four years ago.

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