In modern, farming-based societies where the food is soft and palatable, we can wolf down a meal without needing to mash it up much first. Less chewing makes for weaker muscles, which means our jaws don’t develop as robustly. Another idea is that it’s down to breastfeeding, because the age at which mothers wean their children varies widely, and dictates when they begin chewing more solid food.

The earliest modern human fossil ever found outside of Africa has been recovered in Israel. This suggests that modern humans left Africa at least 50,000 years earlier than previously believed. The upper jawbone, including several teeth, was recovered in a prehistoric cave site.

So what will future archaeologists make of our skeletons, when they examine them from their spaceships? If we’re not careful, they’ll reveal unhealthy diets, staggering levels of inactivity, and a morbid attachment to technology. Rather than having bites, like we do now, where the upper incisors covered the lower ones, previously adults would have had bites where they met instead. To catapult your jaw back to Neolithic times, try pushing out your lower jaw until your upper and lower teeth touch, then attempt to say “fish” or “Venice”. “And so we were thinking about that, what could be the reason,” says Scheffler.

“And he thought it was significant enough to write a whole paper about it! When we’re sitting upright, these hefty objects are balanced neatly on top of our spines. But as we lean forwards to pore over famous dogs on social media, our necks must strain to hold them in place. Shahar thinks the spikes form because the hunched posture creates extra pressure on the place where the neck muscles attach to the skull – and the body responds by laying down fresh layers of bone. These help the skull to cope with the extra stress, by spreading the weight over a wider area.

New research suggests that 40% of 25 individuals buried at Stonehenge weren’t from there — but they possibly transported stones from west Wales and helped build it. From left, Haplocheirus, Xiyunykus, Bannykus and Shuvuuia reveal the lengthening of the jaws, reduction how fast can a hippo run of teeth and changes in the hand and arm. This fossil represents a new piranha-like fish from the Jurassic period with sharp, pointed teeth. An artist’s illustration shows giant nocturnal elephant birds foraging in the ancient forests of Madagascar at night.

The remains were dated to the 16th or 17th Century, and they were positively gigantic. The man’s skull, arm bones, collarbones, and the bones of his lower legs suggested that he had been immensely strong and unusually tall. The discovery of a species that lived 6.6 million years ago in southwestern China suggests that ancient otters had “wolf-like” proportions, and weighed roughly 100 Ibs. The creature — whose skull was excavated in Yunnan province — would have been twice the size of today’s otters. In 2016, researchers discovered ancient collagen and protein remains preserved in the ribs of a dinosaur that walked the Earth 195 million years ago.

Fluoride is a naturally occurring mineral, and as one might expect, it is very useful to restore the mineral qualities of tooth enamel, remineralizing teeth back to being smooth and strong. The most common way dentists use fluoride is by applying a foaming gel to the teeth after thoroughly cleaning them. If you liked this story,sign up for the weekly bbc.com features newsletter, called “If You Only Read 6 Things This Week”. A handpicked selection of stories from BBC Future, Culture, Capital, and Travel, delivered to your inbox every Friday. Intriguingly, the strong men from the Mariana islands also tend to have growths on their skulls. They are thought to have developed for a similar reason – to support their powerful neck and shoulder muscles.