Origin of Life on Earth

Competing Hypotheses

Scientists are considering three main ideas about where life might have originated on Earth:

1. Hydrothermal Vents Hypothesis

   • Suggests life evolved in hydrothermal vents at the ocean's bottom.
   • Current prevailing hypothesis due to substantial support.

2. Surface Pond Hypothesis

   • Life may have evolved in small ponds on the ocean's surface.
   • Initially proposed by Charles Darwin.
   • Supported by some evidence.

3. Extraterrestrial Origin Hypothesis

   • Proposes life originated outside Earth and arrived via meteorites.
   • Based on the slow rate of genetic change, suggesting life couldn’t have originated 3.5 billion years ago solely by Earth’s processes.

Support for Hydrothermal Vents Hypothesis

• Last Universal Common Ancestor (LUCA):
  • LUCA genes (355 identified) suggest an origin in deep-sea hydrothermal vents.
  • Strong consistency found between these genes and life forms in hydrothermal environments.
• 2016 Study:
  • Published in Natural Microbiology, supporting the hydrothermal vents hypothesis.

Educational Material

Three videos will be presented to elaborate on each of these ideas, providing detailed analysis and evidence.