How much life has ever existed on Earth?

All organisms are made of living cells. While it is difficult to pinpoint exactly when the first cells came to exist, geologists' best estimates suggest at least as early as 3.8 billion years ago. But how much life has inhabited ...

How tomato plants use their roots to ration water during drought

Plants have to be flexible to survive environmental changes, and the adaptive methods they deploy must often be as changeable as the shifts in climate and condition to which they adapt. To cope with drought, plant roots produce ...

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