Around 1.7 billion years ago, eukaryotes—the building blocks of complex life—first appeared on Earth, and now scientists have ...

Scientists are trying to understand how complex life emerged on Earth about 2 billion years ago. Our microbial ancestors could be the key.

Our single-celled ancestor lived in a world without plants, animals or oxygen-rich oceans. Yet, this seemingly simple microorganism took the first steps toward complex life. From this ancestor emerged ...

Researchers investigating the origin of complex life on Earth might have just made a major breakthrough. The origin of humanity and the planet Earth is probably debated more than whether the chicken ...

Prokaryotic cells, which include all bacteria and archaea, are ancient, and relatively simple compared to eukaryotic cells, which are found in fungi, plants, and animals. Scientists have long sought ...

The origin of the nucleus remains hotly debated among scientists, but new imaging and genomic data are shedding light on this billion-year-old mystery.

For billions of years after the origin of life, the only living things on Earth were tiny, primitive cells resembling today’s bacteria. But then, more than 1.5 billion years ago, something remarkable ...

For decades, scientists have believed that complex life began when two very different microbes joined forces, eventually giving rise to plants, animals, and fungi. But one major puzzle remained: how ...

Ancient microbes tied to our earliest ancestors could use oxygen, reshaping ideas about how complex life began on Earth.

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For billions of years after the origin of life, the only living things on Earth were tiny, primitive cells resembling today’s bacteria. But then, more than 1.5 billion years ago, something remarkable ...