Scientists have calculated the Earth to be 4.54 billion years old, with an uncertainty of 50 million years on either side. But how did they arrive at that number? Philosophers have debated the ...

A study suggests that this organism likely lived on Earth only 400 million years after its formation. Further analysis also shows that this life form likely sported an early immune system ...

The study also provides a new approach to solving one of the biggest enduring scientific mysteries: when did plate tectonics begin?