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WonderOcean science fact

Hydrothermal vents, hot springs on the deep ocean floor, support dense communities of animals in total darkness. Their food chain starts not with sunlight but with microbes that make food from chemicals in the vent water, a process called chemosynthesis.

Galápagos Rift, 1977

OceanScienceBiologyEvolution

The story behind the card

In February 1977 the geologist Jack Corliss and colleagues took the submersible Alvin down about 2,500 metres to the Galápagos Rift, a crack in the Pacific seafloor, expecting bare rock. Instead they found warm vents ringed with clams, mussels, crabs and tube worms. Vent water is rich in hydrogen sulphide, a gas poisonous to most life, but some bacteria can draw energy from it to build sugars, much as plants use sunlight. Giant tube worms, which have no mouth or gut, house these bacteria inside their bodies and live on what they make. The find changed ideas about where life can exist, on Earth and possibly beyond it.

Türkçe oku
Hidrotermal bacalar, okyanusun derinlerinde deniz tabanından fışkıran sıcak su kaynaklarıdır ve zifiri karanlıkta kalabalık hayvan topluluklarını besler. Buradaki besin zinciri güneş ışığıyla değil, bacadan çıkan sudaki kimyasallardan besin üreten mikroplarla başlar; buna kemosentez denir.
Galápagos Rifti, 1977

Şubat 1977'de jeolog Jack Corliss ve ekibi, Alvin denizaltısıyla Pasifik tabanındaki bir yarık olan Galápagos Rifti'ne, yaklaşık 2.500 metre derinliğe indi. Çıplak kaya bekliyorlardı; bunun yerine çevresi deniz tarakları, midyeler, yengeçler ve boru kurtlarıyla dolu ılık bacalar buldular. Baca suyu, çoğu canlı için zehirli bir gaz olan hidrojen sülfürce zengindir; ama bazı bakteriler, bitkilerin güneş ışığını kullanması gibi, bu gazdan enerji alıp şeker üretebilir. Ağzı ve bağırsağı olmayan dev boru kurtları bu bakterileri vücutlarının içinde barındırır ve onların ürettiğiyle yaşar. Bu keşif, yaşamın Dünya'da ve belki başka gezegenlerde nerelerde var olabileceğine dair düşünceleri değiştirdi.

Sources and further reading

Background reading: Hydrothermal vent
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