Caves: Extreme Conditions for Life

For certain life forms on Earth, conditions that humans and other familiar organisms find hospitable can actually be deadly. Instead of a moderate climate with an atmosphere rich in nitrogen and oxygen, these organisms thrive in very hot or very cold temperatures, or in caves or deep waters where no light penetrates. In this video segment adapted from NOVA, scientists analyze communities of cave-dwelling microbes that live off simple inorganic compounds like iron and sulfur. Based on their findings, the scientists consider whether life might also exist on other planets that contain similar primitive conditions. CREDITS: LICENSE:

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