Extinction occurs when every single member of a species dies, and is unfortunately on the rise. We are currently experiencing an ongoing sixth age of extinction with extinction rates greater than the dinosaur extinction event (K-T extinction). Sometimes referred to as the holocene or anthropocene extinction, this current event is closely linked to human activity. In particular, climate change and habitat loss. Although the future looks grim, life finds a way.

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10 greatest ever beasts

We don't like to see animals go extinct, but we're happy we won't come face-to-face with these colossal creatures, which could crush today’s titans with ease.