Hydrothermal Vents

Discovered in 1977 at the Galápagos Rift, hydrothermal vents overturned biology. Here, in eternal darkness and near-freezing water broken by 400 C jets, live communities that get all their energy from chemosynthesis - bacteria oxidising hydrogen sulfide. Giant tube worms, vent crabs, vent shrimp, and specialised fish thrive on this alien chemistry. Life without sunlight was declared impossible before 1977; now we know its foundational to potentially most life on Earth.

Superheated water (up to 400 C at chimney vents) mixing with 2 C deep-sea water. High pressure (200+ atm). Chemical soup of sulfides, methane, iron, manganese.

Chemosynthetic bacteria as primary producers. Giant tube worms (Riftia pachyptila) house symbiotic bacteria. Vent crabs, vent shrimp, and specialised fish complete the food web.