A Fossil First: Scientists Find 1.5-Million-Year-Old Footprints of Two Different Species of Human Ancestors at Same Spot Nov. 28, 2024 — More than a million years ago, on a hot savannah teeming ...

Mar. 10, 2025 — It is widely believed that Earth's atmosphere has been rich in oxygen for about 2.5 billion years due to a relatively rapid increase in microorganisms capable of performing ...