In the 1970s, scientists discovered communities of living organisms thriving on the deep ocean bottom, too far down for sunlight to reach. Huge red worms living in tubes as well as new species of clams, jellyfish, crabs and other ocean animals were clustered around cracks or vents on the seafloor. This is where molten lava had oozed out from the depths of the planet, producing currents of heated water rich in dissolved minerals.
What were animals living on? There must be some food producers to support all these consumers. But how could food producers make food without a supply of sunlight energy?
Reseachers found that the food producers in these ocean vent communities are bacteria that are very different from those living at Earth surface. Instead of photosynthesis, they use a process called chemosynthesis to store energy in a special compound and convert chemicals to biochemicals used for food and building materials. Scientists classify these bacteria as lithotrophs [ rock eaters ]. They get energy by oxidizing minerals such as sulfates, nitrates and iron compounds as well as chemicals such as hydrogen sulfide and ammonia. These were chemicals that were plentiful on the ancient Earth before photosynthesis generated oxygen for the atmosphere.
Researchers believe that the bacteria that live by chemosynthesis are very ancient and perhaps the first living creatures that appeared on our planet. They have named them Archaebacteris or Archea from the Greek word for ' ancient '.
What were animals living on? There must be some food producers to support all these consumers. But how could food producers make food without a supply of sunlight energy?
Reseachers found that the food producers in these ocean vent communities are bacteria that are very different from those living at Earth surface. Instead of photosynthesis, they use a process called chemosynthesis to store energy in a special compound and convert chemicals to biochemicals used for food and building materials. Scientists classify these bacteria as lithotrophs [ rock eaters ]. They get energy by oxidizing minerals such as sulfates, nitrates and iron compounds as well as chemicals such as hydrogen sulfide and ammonia. These were chemicals that were plentiful on the ancient Earth before photosynthesis generated oxygen for the atmosphere.
Researchers believe that the bacteria that live by chemosynthesis are very ancient and perhaps the first living creatures that appeared on our planet. They have named them Archaebacteris or Archea from the Greek word for ' ancient '.
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