Life loves Earth. Not only do we see an abundance of life across the globe today but palaeontologists, through the study of the remains of plants and animals, are kept busy by a steady stream of new discoveries of species from long ago. Unearthing dinosaurs is hard to top, but palaeontologists keep trying! They’ll probably never run out of work, because the number of species currently alive is only a fraction of those that have previously evolved, lived and since become extinct on Earth.

Dig in

Palaeontologists can tell that most species tend to hang around for anything between 1 million to 11 million years. Modern humans have been around for 200,000 years so far.

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Done to death

Rather worryingly, there have been five mass extinctions in the history of Earth. It seems as if old age isn’t the only reason why a species dies out.

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The first was 444 million years ago, when 85% of all species on Earth died as the planet froze over. 

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The second was 375 million years ago. 75% of all life suffocated as oxygen was sucked from the water; scientists suspect this may have been the result of algal blooms.

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The biggest extinction of all was the third, around 250 million years ago. A mind-blowing 96% of all life on Earth was extinguished as temperatures surged, and the oceans acidified and stagnated.  

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The mysterious fourth extinction was 200 million years ago. No clear cause has yet been discovered for the extinction of around 80% of life at this time. 

The mass extinction that annihilated the dinosaurs was the most recent, devastating the Earth only 65 million years ago. Scientists are pretty certain that this extinction was caused by a large meteorite hitting the Earth and killing off 76% of life.

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The mass extinction that annihilated the dinosaurs was the most recent, devastating the Earth only 65 million years ago. Scientists are pretty certain that this extinction was caused by a large meteorite hitting the Earth and killing off 76% of life.

Disappearing act

Human activity is now directly influencing extinction. We’ve witnessed the disappearance of 60% of animal life since 1970. The world’s environmental experts are warning that the annihilation of wildlife is an emergency that threatens the future of our planet.

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