How Bacteria Nearly Destroyed All Life

About two and one-half billion years ago, life on Earth was still in its infancy. Complex organisms such as plants and animals had not yet appeared, but the planet was teeming with microscopic bacteria which thrived in the temperate and nutrient-rich environment. Greenhouse methane lingered in the atmosphere and trapped the sun's warmth, creating a climate very accommodating to the stew of microbes life that made their home on primitive Earth.