Related topics: plants

Expert explains why North American bird populations are declining

According to recent data, bird populations in North America have declined by approximately 2.9 billion birds, a loss of more than one in four birds since 1970. Experts say this bird loss will continue to grow unless changes ...

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 ...

Permafrost: A ticking time bomb beneath our feet

Nearly a quarter of the Earth's land surface is permanently frozen. These areas, known as permafrost, are found in northern polar regions and at high altitudes. But the permafrost is now starting to thaw—with potentially ...

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