Oldest microfossils suggest life thrived on Earth about 4 billion years ago
Ancient microbes were spewed from deep-sea hydrothermal vents, study claims
![hematite](https://i0.wp.com/www.sciencenews.org/wp-content/uploads/2017/03/022817_MR_oldest-fossil_main.jpg?fit=860%2C460&ssl=1)
SIGNS OF LIFE In rocks left over from ancient hydrothermal vents, these microscopic tubes of hematite, an ore of iron, may be remnants of early microbes.
M. Dodd