Life 1: Many animals and plants are in great danger because of some people. They may become extinct very soon.
Since life on Earth began billions of years ago, there have been five mass extinctions. That's when almost all life forms (plants, animals and others) have died out. In each of these extinctions, there seems to have been some major catastrophe which upset the planet, making it hostile to most life. Scientists now know that these extinctions can be linked to things like lots of volcanic eruptions or to the Earth being hit by comets or asteroids.

We are now in the middle of a sixth mass extinction (you may not have noticed, but scientists have) in which different types of animals, plants and other life are dying out as fast as in the earlier extinctions (see my guide called Life in Danger). This time, the cause is not volcanoes, asteroids or comets but — you guessed it — greedy people: future-eaters.

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