For the last twenty million years, Chile's Atacama Desert has been the driest, most inhospitable place on Earth. But deep below the surface of this unimaginably arid world, microbes are flourishing without even oxygen or sunlight. Meet the extremest extremophiles.
This is Siphusauctum gregarium, a creature that lived in the ocean 500 million years ago. It's so completely strange that it's taken scientists 30 years just to figure out how to describe it. It's literally like nothing else on Earth.
Actually, Mesodinium chamaeleon is both. This single-celled organism definitely eats other creatures, which makes it an animal. But it also absorbs algae cells that can then give it extra energy through photosynthesis. So what on earth is this strange creature?
About 2.5 billion years ago, our planet had virtually no oxygen, and lifeforms were primitive. Then, oxygen levels suddenly spiked, the entire landscape of the planet changed, and we were on our way to complex life. Now, at last, we know why.
The fossil you see here was found in Doushantuo, China, one of the world's richest fossil formations. It looks like grains of sand, but nobody is sure what it actually is, whether it's animal, bacteria, or something even weirder.
Fairy wasps are some of the tiniest creatures on Earth, an entire insect roughly the size of a single-celled organism like an amoeba. That means their individual cells must be incredibly tiny...and that requires losing much of their nervous system.
The Last Universal Common Ancestor is the great-grandparent of everything that has ever lived on Earth. Scientists had long assumed it was a crude, simple thing, more a chemical mishmash than anything else. But our earliest ancestor holds some surprises.
One of the biggest evolutionary hurdles for life on Earth was the jump from single-celled to multi-cellular organisms...or at least, that's what we thought. Scientists set out to replicate this evolutionary leap in laboratory conditions. It took them two months.
As recently as 600 million years ago, oxygen levels were extremely low on Earth, only about a tenth of what they are today. So how did ancient animals move around and avoid mass asphyxiation?