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Are we entering the sixth major extinction on Earth?


Extinction Warning Signs
The dodo bird is just one example of a species that went extinct due to human interference.
The dodo bird is just one example of a species that went extinct due to human interference.
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It can be difficult to grasp how the extinction of a seemingly insignificant life form could impact the rest of the world. But it's true that one life form's disappearance could cause enormous problems for life in general.

Let's consider a fictional example. Imagine a lake teeming with life. There are fish and amphibians living in the lake, and insects on and around it. Reptiles, birds and mammals live around the lake and depend upon it, too. Now imagine that a species of insect at that lake dies out for some reason. The impact of this event could be catastrophic.

First, any other insects, fish or amphibians that fed upon the now-extinct insect would be affected. These creatures would either have to adapt by eating something else or would die out. Move one step further up the food chain and you'll see that it's a domino effect: The creatures that fed upon the animals lower on the food chain would see a decrease in their food supply.

Now imagine that scenario taking place across the entire world at varying levels of the food chain. According to Richard Leakey and Roger Lewin, authors of "The Sixth Extinction," we could lose half of all species on Earth by 2100. They point out that species extinction can happen even if we stop destructive habits now. Small populations may succumb to sudden events ranging from natural disasters to disease. But if we continue to clear away rainforests the situation will be even worse.

What can we do about it? It'll require humans to make some sacrifices. Decreasing our carbon footprint is a good start. Reducing the amount of meat we eat can also help since raising stock requires ranchers to clear land. Cutting back on destructive habits could save thousands of species over the next several decades. And it might just save us, too.

Learn more about biodiversity, ecology and extinction by following the links on the next page.


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