The Big Bang created a cloud of dust and rocks that included a lot of rocks that were made of ice, like giant snowballs. That's where some of the water came from.
An expert panel has announced that we truly are living in the geological era defined by humanity's fingerprint. But is it as simple as that, and does it leave "Anthropocene science" open to attack?
Despite claims about its age, puzzling combinations of features from Homo naledi gives it an uncanny resemblance to human beings.