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BBC – Future – How modern life transforms the human skeleton

It all began with a goat. The miserable animal was born in the Netherlands in the spring of 1939 – and its outlook does not look good. On the left side of his body, the bare coat of hair marked the place where his front leg was supposed to be. To his right, his front leg was so deformed that he was more than a hoof with a hoof. Walking on four legs would be, say, problematic.

But when she was three months old, the small goat was accepted by a veterinary institute and moved to herbaceous field. There he quickly improvised his peculiar style of movement. As he pressed his legs forward, he pulled himself up until he stood up on his hind legs and jumped. The end result was somewhere between the kangaroo hops and the rabbit, though it probably was not that majestic.

Unfortunately, the skilful goat was involved in an incident shortly after his first birthday, and he died. But in his skeleton there was a last surprise

For centuries, scientists thought our bones were fixed-that they grew in a predictable way, according to the instructions inherited by our parents. But when a Dutch anatom examined the skeleton of the goat, they discovered that he had begun to adapt. Bones in his thighs and legs were thicker than you would expect while those in his ankles were stretched. Finally, the toes and thighs were unusually sloping to accommodate a more upright posture.

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Today, we find out that our skeletons are surprisingly plastic. The clean white remains that appear in museums may look solid and inert, but the bones under our flesh are very lively ̵

1; actually pink with blood vessels – and are constantly being destroyed and restored. So, although each person's skeleton develops according to a rough template displayed in their DNA, it is adapted to accommodate the unique stresses of their lives.

This has led to a discipline known as "osteobiography" – literally "the biography of bones" – which involves skeletal viewing to find out how his owner lived. He relies on the fact that certain activities, such as walking on two legs , leaving a predictable signature behind them, such as stronger bones on the thigh The discovery of curious growth of the spines on the back of the skulls of many people to the awareness that our jaws are diminishing to the mysterious finding that German youths have, narrow elbows than ever before, it is clear that modern life affects ours

As an example of how osteobiography works, take the secret of the "strong men" of Guam and the Marian Islands, which begins with the discovery of a male skeleton on Tianan Island. 1600 miles (2560 km) east of the Philippines in the Pacific, in 1924. The remains are dated to the 16th or 17th centuries, and they were positively giant, the human skull, the bones of the hands, the clavicles and the bones of its lower legs suggested that he was extremely loud and unusually tall.

The find fits well into local legends of enormous ancient rulers who are capable of true heroic physical feats. Archaeologists called it Taotao Tagga – a "Tagga guy" – after the famous mythical head island of Taga, known for its superhuman powers.

When other graves were discovered, it became clear that the first skeleton was not an anomaly; in fact, as well as a fiction, Tianan and the surrounding islands were home to a race of extremely muscular men. But where did they get their strengths from?

When this happens, the remains of the strong men are often in the answer. In the case of Tag, he was buried between 12 impressive carved stone columns that would initially support his house. At the same time, a closer examination of his bones and others reveals that they have similar characteristics to those of the Tonga archipelago in the southern Pacific, where people make many stones and build massive rocks.

The largest such house on the island had pillars high 16 feet (5 meters) and weighing about 13 tonnes each – about two adult African elephants. It was not a mysterious race of muscular giants; men have achieved their powerful buildings through pure, hard work.

If the same technique was used in the future to get together how people live in 2019, scientists will find characteristic changes in our skeletons that reflect our modern lifestyle. 19659002] "I have been a clinician for 20 years, and in the last decade alone, I have found that my patients have this growth of the skull," said David Shahar, a health scientist at the University of Sunshine Coast, Australia

The characteristics similar to a spike, also known as the "external obtuse protrusion", is located at the lower back of the skull, just above the neck. If you have one, you can probably feel it with your fingers – or if you are bald, it can even be seen in the back.

Until recently, this type of growth was considered extremely rare. In 1885, when the former was investigated, the famous French scientist Paul Broca complained that he had a name at all. "He does not like him because he has studied so many specimens and has not seen anyone who has it."

Feeling something may have risen, Shahar decided to investigate. Together with his colleague, he analyzed over a thousand X-ray skulls from people between 18 and 86 years of age. They measured all the spikes and noticed the position of each participant.

What the scientists found was astounding. The jump is much more widespread than expected, and much more common in the youngest age group: one in four people between the ages of 18 and 30 has had growth. Why can this be? And should we worry?

Shahar believes that spike blasting is related to modern technology, especially our latest obsession with smartphones and tablets. As we bend over them, we raise our necks and hold our heads forward. This is problematic because the average head weighs about 4.5 pounds – about a great watermelon.

Text on the Neck

When we sit upright, these heavy objects are balanced on the top of our thorns. But while we lean forward to peer over the famous dogs in social media, our necks need to be tense to keep them in place. Doctors call the pain that can cause the "neck of the text". Shahar thinks the spikes are formed because the bent posture creates additional pressure on the place where the neck muscles are attached to the skull – and the body reacts by placing fresh layers of bones. They help the skull to cope with extra stress by spreading the burden over a wider area.

Of course, the bad posture was not invented in the 21st century – people have always found something to suggest. Why did not we get the bulges from the books then? One of the possibilities lies in the time we spend on our phones, compared to how long a person would spend reading. For example, even in 1973, long before the most advanced manual shifts were invented, the average American usually reads about two hours each day. Unlike today, people spend nearly twice as much time on their phones.

Indeed, for Shahar, the biggest surprise was how big the spikes were. Prior to the study, the latest study was conducted in an osteology laboratory in India in 2012. It is a laboratory specializing in bones – as you can imagine, they have a lot of skulls – but the doctor found only one with growth there. It has a size of 8 mm, which is so small that it would not even be included in Shahar's results. "And he thought it was important enough to write a whole document for him!" He says. In their own study, the most significant increases were 30 mm in length.

Interestingly, the mighty men of the Mariana Islands are also inclined to grow up on their skulls. It is believed that they have evolved for a similar reason – to support their strong muscles of the neck and shoulders. Men may have been wearing heavy weights by cutting them off the poles on their shoulders.

Shahar says it is likely that modern spikes will never disappear. They will continue to grow bigger – "Imagine if you have stalactites and stalagmites if nobody worries them, they will just keep growing" – but they rarely cause any problems themselves. If there is any problem, it will probably be caused by the other compensation the body has to make for our entire adjustment.

On the other side of the world, in Germany, scientists have discovered another strange development: our elbows are shrinking. Christian Scheffler, an anthropologist at the University of Potsdam, studied body measurements taken by students when he noticed the trend.

Child skeletons become more fragile each year

To see exactly how their skeletons have changed Over time, Scheffler has undertaken a study of how healthy or "big bones" are children between 1999 and 2009. This included the calculation of their "frame index", which is how the height of a person compares to the width of the elbows. She then compares her results with those from an identical study, which is 10 years older. She found that children's skeletons were becoming more fragile every year.

"That's why we thought about what the reason could be," says Schaeffler. Her first idea was that it could be genetic, but it is hard to see how the DNA of the population can change so much in just 10 years. The second is that perhaps children suffer from poor nutrition, but this is not really a problem in Germany. The third is that today's young people are a generation of potatoes on the couch.

To find out, Scheffler conducted a new study – along with some colleagues this time – asking the children to fill out a questionnaire about their daily habits, and to carry a step counter for a week. The team found a strong link between how healthy the children's skeletons and the amount of walking they are doing.

It is now well known that every time we use our muscles, we help increase the mass of bones that support them. "If you use them again and again, they build more bone tissue, which is measured as a higher density and a larger bone circumference," says Scheffler. The skeletons of the shrinking children look like a simple adaptation to modern life, as it does not make sense to grow bones you do not need.

But there was a surprise that was in the data: Walking was the only kind of exercise. it seems to have had some effect. Schaeffler believes this is because even the most enthusiastic sports fans actually spend very little time practicing. "It does not help if your mother takes you to the car for one or two hours a week," she says.

And although nobody has watched the relationship stay with adults, it's likely that the same rules apply: it's not enough just to hit the gym several times a week without going long distances. "Because our evolution tells us we can walk nearly 30 km a day."

The last surprise hidden in our bones may have happened for hundreds of years, but we just noticed. Already in 2011, Noreen von Kramon-Taubendel of the State University of New York in Buffalo studied skulls. As an anthropologist, she wanted to know if it was possible to tell where it came from, simply by looking at its shape.

In search of an answer, Kramen-Taubbeld searches collections of museums from all over the world to compare the skulls and carefully measure them. In fact, in general, you can tell approximately where the skull was from and with whom its owner was connected, only by its shape. But there was one part in which it was not like this: the jaw.

Soon it became clear that instead of being determined by genetics, the shape of the jaw is most affected by whether a man has grown into a hunter-gathering society, or a community that relies on agriculture. Cramon-Taubadel thinks it all depends on how much chewing we make while we grow. "If you think about orthodontics, obviously the reason we do it with teenagers is that their bones are still growing," says Kramon-Taubbell. "Bones are still prone to this age and they will react to different types of pressure."

In modern agriculture-based societies, where food is soft and delicious, we can wander food without having to smash it first. Less chewing results in weaker muscles, which means that our jaws do not develop so much. Another idea is that it is until breastfeeding because the age at which mothers wean their children varies widely and dictates when they begin to chew a harder diet.

In post-industrial populations, it is much more likely to suffer from tooth problems – such as teething and teeth

But we still do not have to complain about our farmer's groin. Cramon-Taubadel says the effect of chewing on the lower part of the face is actually pretty fine with the naked eye. Instead it is likely to manifest in our teeth. "So the main problem is that, especially in the post-industrial population, we are much more likely to suffer from tooth problems – teeth crowding, curving teeth, etc.," she says. "Studies currently show that having a slightly more biomechanically difficult diet, especially in children, may be helpful in counteracting some of the imbalance between how our teeth grow and develop and work."

And here is an unexpected turn. It is unlikely that it now appears that the changes in jaws and teeth have had at least one positive side effect – the way we talk. A recent study found that since societies discovered neolithic agriculture about 12,000 years ago, the changes in our bites allowed us to pronounce new sounds like "f" and "v". Researchers have calculated that this makes the languages ​​people talk of containing only 3% of these difficult sounds to 76% today. lower, earlier adults would have bites where they met. To catapult your jaw back into the Neolithic, try to push your lower jaw until you touch the upper and lower teeth, then try to say "fish" or "Venice."

So what will future archaeologists do from our skeletons when they explore them from their spaceships? If we are not careful, they will uncover unhealthy diets, stunning levels of inactivity and painful attachment to technology. [196590042] – [196599045] Join the more than one million fans of the future by liking Facebook or follow us on . If you like this story, sign up for the bbc.com weekly newsletter called "If you're just reading 6 things this week," a selection of BBC Future stories , Culture, Capital and Travel delivered to your mailbox every Friday.

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