In order to understand where hearts came from, we have to go back to the earliest common ancestor of everything that has a heart. It took hundreds of millions of years, and countless different iterations of the same basic structure to...

Toxodon was one of the last members of a lineage that vanished 11,000 years ago after thriving in isolation for millions of years. And its fossils would inspire a revolutionary thinker to tackle a bigger mystery than Toxodon itself:...

Untangling the origins of Beelzebufo -- the giant frog that lived alongside the dinosaurs -- turns out to be one of the most bedeviling problems in the history of amphibians.

Only a handful of Denisovan fossils have been identified. In the absence of actual body fossils, it’s impossible for us to reconstruct their morphology, right?

Paleontologists found a small theropod dinosaur skull right on top of a nest of eggs that were believed to belong to a plant-eating dinosaur. Instead of being the nest robbers that they were originally thought to be, raptors like this...

This video contains images and video of snakes and spiders. It's possible Euchambersia possessed venom about 20 million years before the first lizards and over 150 million years before the first snakes evolved. We’ve teamed up Sarah...

Around the time that some of our fishapod relatives were crawling out of the water, others were turning around and diving right back in.

Weasels have an extreme body plan that may push the boundaries of what’s metabolically possible. So when and how did this happen? Why'd the weasels get so skinny?

A 9,500-year-old burial in Cyprus represents some of the oldest known evidence of human/cat companionships anywhere in the world. But when did this close relationship between humans and cats start? And how did humans help cats take over...

The rise and fall of ancient walruses, and how modern ones got their tusks, is a story that spans almost 20 million years. And while there are parts of the story that we’re still trying to figure out, it looks like tusks didn’t have...

How did seahorses — one of the ocean’s worst swimmers — spread around the globe? And where did they come from in the first place?

The story of the egg spans millions of years, from the first vertebrates that dared to venture onto land to today’s mammals, including the platypus, and of course birds. Like chickens? We’re here to tell you: The egg came first.

These odd rodents belong to a genus known as Ceratogaulus, but they’re more commonly called horned gophers, because, you guessed it, they had horns. And it turns out the horns probably had a purpose - one that rodents would likely...

Before the start of the Eocene Epoch about 56 million years ago--Antarctica was still joined to both Australia and South America. And it turns out that a lot of what we recognize about the southern hemisphere can be traced back to that...

Figuring out what this creature’s face actually looked like would take paleontologists years. But understanding this weird animal can help us shine a light on at least one way for ecosystems to bounce back from even the worst mass...

The mammoths fossils found on the Channel Islands off the coast of southern California are much smaller than their relatives found on the mainland. They were so small that they came to be seen as their own species. How did they get...

Our DNA holds thousands of dead genes and we’ve only just begun to unravel their stories. But one thing is already clear: we’re not just defined by the genes that we’ve gained over the course of our evolution, but also by the genes that...

The Toba supervolcano was the biggest explosive eruption of the last 2.5 million years. And humans were around to see it, or at least feel its effects! But what were those effects?

Throughout the first half of the 20th century, Neandertals were thought to have been…primitive. Unintelligent, hunched-over cavemen, for lack of a better word. But the discoveries made in that Iraqi cave provided some of the earliest...

All of today’s big cat species evolved less than 11 million years ago and yet their evolutionary history remains an almost total mystery. But scientists have recently discovered a major clue about the origins of the big cats, one that...

Fossil evidence suggests Diictodon used burrows to breed, and that a parent stayed behind to feed and protect their young. And the parent that stayed behind? It might’ve been the male.

People have been discovering the traces and remains of prehistoric creatures for thousands of years. And they’ve also probably been telling stories about fantastic beasts since language became a thing. So, is it possible that the...

For decades, scientists have been studying the cause of the Younger Dryas, and trying to figure out if something like it could happen again. And it turns out that what caused this event is the subject of a heated debate.

In some places, the rocks below the Great Unconformity are about 1.2 billion years older than those above it. This missing chapter in Earth’s history might be linked to a fracturing supercontinent, out-of-control glaciers, and maybe the...