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What If Steller's Sea Cow Hadn't Gone Extinct?
Meet the Steller's sea cow — a real giant sea mammal up to 30 feet long that ate kelp and had no teeth. Learn how it was hunted to extinction just 27 years after being discovered.
How it works
- Press play to start the video.
- Videos 5 minutes or longer pause once or twice for a quick check. Get it right and you're on your way. If not, you'll see a friendly explanation and the video simply keeps going. Short videos skip the checks.
- At the end there's a 3-question test. Score 60% or more to complete the lesson, and 80% or more to master it. You can always watch again and try for a higher score.