Earth & Conservation

Why The Next Mass Extinction May Already Be Here

There have been 5 mass extinctions on earth so far and many indicators show us that we may be in the throes of a 6th mass extinction now!

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There's been a lot of talk about climate change and global warming, and for good reason: there have been five "mass extinctions" on Earth. More than 99 percent of all species that have ever lived on Earth are now extinct, and 95 percent of those either died out because they couldn't compete successfully for food and resources or failed to adapt to changes in their local environment. In other words, weather and climate have killed billions of life forms during Earth's 4.5 billion-year history.

The last mass extinction on Earth was the End-Ordovician, which occurred about 440 million years ago. It's estimated 82 to 88 percent of all species living on earth at the time were wiped out: 26 percent of all marine families and 60 percent of all genera. The cause? The world entered an intense ice age at the end of the Ordovician Period. Massive ice sheets that formed caused the sea levels to drop dramatically.

More and more research is showing that we are entering the sixth great extinction. A study published this year in Science Advances showed that we're losing vertebrates at 100 times the rate that we should be. And it's being caused by humans. Is there anything we can do at this point? Trace explores.

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Learn More:
Big Five mass extinction events (BBC Nature)
"Although the Cretaceous-Tertiary (or K-T) extinction event is the most well-known because it wiped out the dinosaurs, a series of other mass extinction events has occurred throughout the history of the Earth, some even more devastating than K-T. Mass extinctions are periods in Earth's history when abnormally large numbers of species die out simultaneously or within a limited time frame."

End Triassic Mass Extinction (Natural History Museum):
"After the cataclysmic Late Permian mass extinction, it took 10-20 million years for life to recover its previous diversity. But it did recover, and in significant new ways. This was particularly true of vertebrates. Mammal-like reptiles flourished. Walrus-like reptiles, placodonts, appeared in the shallow seas. Sharks and fish diversified. And giant reptiles - the dolphin-like ichthyosaurs - became the top marine predators."

End-Ordovician mass extinction (Natural History Museum):
"Many experts believe the extinction event at the end of the Ordovician Period was the second most severe of the great extinctions. Virtually all life was in the sea at this time so it was mostly marine animals that were affected.