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This belongs to an extinct animal—but what is it? You might have seen this shape before.
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It’s a fossil shark tooth! Here’s how big its whole mouth was. This extinct shark is called a megalodon, which means “large tooth”!
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Here’s how big a megalodon would have been compared to a great white shark! Megalodons ate whales and other sharks too!
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A farming family in Michigan, USA, found something strange in their yard—a huge fossil! What kind of animal is this fossil from?
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It’s the skull of a mammoth! That’s the ancestor of an elephant! Ancient people lived when mammoths were alive!
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Here’s part of a fossil of another giant creature. Can you tell what kind of creature it is? Hint: Do you see wings?
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It’s a giant dragonfly! Before dinosaurs roamed the Earth, there were giant insects. Check out the size of these models!
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This fossil animal is the size of a small car. It has a round, hard back...does it look like any living animals to you?
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Hint: It’s related to one of these three animals. Which one do you think it’s related to and why?
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It’s related to armadillos! It’s called a glyptodont—here’s another fossil of one. It was huge, and had a spiky tail it used for fighting!
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This is a sloth from South America. What do you think a sloth that lived a long time ago (a sloth’s ancestor) might look like?
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Today, sloths climb trees and don't usually stand up (they crawl). But their ancestors were as big as elephants and stood tall!
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Voting for this episode is now closed. Would you like to vote on the most recent poll?

We pulled three questions from our jar. Which question do you want to explore?

Illustration of a glass jar with a 'questionmark' label
  • Why can some animals see in the dark?

    -Bella, 5th Grade

  • Why can vultures eat dead stuff and not get sick?

    -Pranav, 4th Grade

  • Are black cats really bad luck?

    -Vincent, 3rd Grade

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What’s the biggest shark that ever lived?

Watch the video to discover the answer and don't forget to vote for next week's question. There are mysteries all around us. Have fun and stay curious!