In 2017, Briana Pobiner, a paleoanthropologist at the Smithsonian National Museum, pointed a magnifying lens at a 1.45 million-year-old tibia and saw a series of neat slashes. The bone belonged to the National Museums of Kenya in Nairobi, where Pobiner had gone to look for animal tooth marks on ancient hominin bones. While researchers generally assume that animals killed and ate our ancient ancestors, relatively little evidence has ever come to light.But this was a different kind of evidence, as ...read more

If you took our whole planet and ground it up into a powder, then analysed that powder for its elemental composition, what would you find? A third of the powder would be iron, another third would be oxygen. Of the remaining ~35%, 30% of it is magnesium and silicon. Most people would guess that maybe elements like carbon or hydrogen would be next on the list ... but they'd be wrong. The element that ends up at #5 on the list is sulfur. Now, this exercise of thinking of a "bulk Earth" shows how bi ...read more

Pterosaurs, which means winged lizard in Greek, are often referred to as flying dinosaurs, but they aren't actually dinosaurs. They're an extinct group of flying reptiles that ruled the skies starting 225 million years ago. Still, they're more closely related to birds and dinosaurs than they are modern reptiles. And they were also the first vertebrae to leave land and take to the skies.The Evolution of Pterosaurs(Credit: Akkharat Jarusilawong/Shutterstock)The earliest pterosaurs were smaller ...read more

The ocean is unfathomably deep.To try to fathom it, picture trekking from sea level to the top of the world’s tallest peak, Mount Everest. If it was inverted above the Mariana Trench, the submerged tip would come more than a mile short of the seafloor. This deepest region known in our seas — a crescent-shaped canyon near Guam and the Mariana Islands — is located in the western Pacific Ocean. How Deep Is the Mariana Trench?Some measurements in the Mariana Trench have charted depths exceedi ...read more

The content of this article may be triggering. Reader's discretion is advised. Most of us have experienced some type of toxic relationship. Maybe it's a partner, friend or family member — but no matter who they are, whenever we're around them, we're left feeling like less than our best selves. Research has shown that the quality of our relationships also impacts our physical health. Rosie Shrout, an assistant professor in human development and family science at Purdue University, says that t ...read more

The unnerving legend of the merchant ship Mary Celeste has persisted for more than 150 years. In late 1872, the ship left New York. About a month later, it was spotted near the Azores, just bobbing along. The crew on a passing ship sent out several unanswered signals. Sensing something was amiss, a few approached in a lifeboat.The surprised sailors found the Mary Celeste abandoned. There were no signs of life — or death. The ship’s wheel was eerily spinning on its own, and everything was le ...read more

As the largest-ever marine predator, the megalodon shark made infamous by Hollywood, measured up to 50 feet in length and was surprisingly warm-blooded, according to a new study published in Proceedings of the National Academy of Sciences. This keen adaptation allowed the “meg” to venture into cold waters and extend its range, but paradoxically, it also bled off crucial energy, which may have contributed to the species’ extinction.Read More: The Mystery of the Megalodon and What Scientists ...read more

Appreciating beauty is part of most people’s everyday lives. We find it in the natural world, in one another, in art and even in ideas. It feels good when we see something beautiful.But this appreciation of beauty presents a slight paradox.Studies on human aesthetic preferences have found that our evaluations of beauty converge on certain features: simplicity, symmetry, juxtapositions of color, and particular shapes, ratios and geometries. And yet, individuals can possess vastly different noti ...read more

Temnothorax nylanderi is a low-key species of ant found mostly in Europe, where it builds nests in tree bark and rotting branches and other woody, secluded places. This tiny brown arthropod leads a quiet life, preferring shade and shelter and staying out of the way of the woodpecker’s bill.But for all this quiet, T. nylanderi faces a strange, alien threat in the form of a parasite that turns its members into yellowed, sedentary oafs. These compromised individuals hang out in the nest, not doin ...read more

Most dog owners are familiar with their pups' enthusiasm for food, whether it's begging for a bite, scavenging crumbs or munching on grass. It seems like dogs can eat almost anything — but should they? Research suggests that, with a few key exceptions, dogs have pretty flexible diets. In fact, their ability to eat a wide variety of foods likely played a major role in making dogs the human companions they are today. However, just because a food doesn’t hurt your pup, doesn’t necessarily m ...read more