Tarantula treat.

A young girl in Cambodia pops the legs of a fried tarantula into her mouth.

Is this girl tackling a dare for the TV show Fear Factor?. Not quite. Treats like this one are considered a delicacy for many people in Cambodia.

Turns out, this eight-legged creature has many of the qualities that make for a tasty snack. For one, like all arachnids, tarantulas have an exoskeleton. This protein-containing body armor ensures that each bite will be crunchy, explains biologist David George Gordon, author of The Eat-A-Bug Cookbook.

Plus, unlike a human's circulatory system, where oxygen-rich blood gets shuttled around the body within enclosed vessels, tarantulas have an open circulatory system. The spider's simple heart--made up of a muscular tube with an opening on both sides--pumps bloodlike fluid into the body cavity. There, the fluid surrounds the spider's internal organs, providing the organs with oxygen. This blood-pumping system means that tarantula bodies are full of fluids rather than rigid vessels. Result? "They are crunchy on the outside, soft on the inside," says Gordon.

But before spider vendors in Cambodia plop an arachnid into a deep fryer, Gordon says they generally remove the spider's pair of poisonous fangs and its dense coat of hairs. When Gordon cooks up a tarantula, he pays special attention to removing the quill-like hairs on the spider's abdomen. To defend itself, a tarantula will use its back legs to kick off these urticating hairs, and send them flying toward potential attackers. Once a "barb" pierces an attacker's body, it digs into tissues. There, it causes pain and irritation. For a spider snacker, the piercing hairs would mean a scratchy meal.

If you think the idea of a girl biting into a tarantula is bizarre, you may want to think again. "Except in Europe, the United States, and Canada, people all over the world eat some kind of insect or spider," says Gordon. That's some food for thought.