How can two seemingly unrelated species that live in isolation from each other evolve into identical forms?

When Australia became separated from the other continents, its species evolved in isolation. And yet, some of the Australian animals evolved in exactly the same way as the other animals in the world. How?

How Evolution Works

Evolution is fascinating because it attempts to answer one of the most basic human questions: Where did life, and human beings, come from? The theory of evolution proposes that life and humans arose through a natural process.

How Extinction Works

Whether they're big or small, extinctions change the world. And while extinctions themselves are all about change, the study of extinction is all about uncertainty. Anything that lives can become extinct, but how do scientists know when it happens?

How Human Migration Works

Where did humanity begin, and how did we get to where we are now? Did we really all begin in Africa? What made us leave?

How Natural Selection Works

If nature is red in tooth and claw, then "survival of the fittest" sounds like a fight to the death. Natural selection is what drives evolution. Is it true that only the strong survive?

How Symbiosis Works

One kind of flatworm doesn't have a working mouth, because the algae that lives inside of it makes food for the worm. Symbiosis is crucial to the survival of many species. In fact, you're a symbiote yourself.

Is an ancient sea scorpion the largest bug ever to live on Earth?

The sea scorpion may have been the largest bug to ever live on the Earth, according to a recent find. Learn more about the giant sea scorpion.

Is there such a thing as a truly unselfish act?

Have you ever done something for someone else just because it was a nice thing to do? Do people perform unselfish acts because it feels good or is it just something society wants us to do?

What happens when animals evolve in isolation?

Polar bears evolved to blend in with the terrain so they could hunt better. What causes one group of animals to split off from the rest of the species and develop new genetic traits?

Will we soon be extinct?

A mass extinction on Earth is long overdue, according to population ecologists. Find out what Earth's fossil record may be telling us about our future.

What is a fossil?

We can see dinosaur and plant fossils at just about any natural museum. What exactly are fossils, though, and how do they form? Find out the answers to these questions in this article from HowStuffWorks.