All organisms are made of living cells. While it is difficult to pinpoint exactly when the first cells came to exist, geologists' best estimates suggest at least as early as 3.8 billion years ago. But ...

For decades, scientists have searched for clues to how life first emerged on Earth. Many theories focus on simple molecules reacting in water or on fragile protocells drifting in ancient seas. A new ...

Scientists have estimated how many cells have occupied Earth since the origin of life on the planet. When you purchase through links on our site, we may earn an affiliate commission. Here’s how it ...