Uploaded June 2026 | Updated September 2026, 3 weeks ago

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Would you let a leech feed on your arm for science? 🩸 Entomologist Tim Cockerill did just that.⁠
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He knew leeches have around 300 teeth...and still did it. If that isn't commitment to science!

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#leech #biology #scienceexplained #naturescience #bloodletting #historyscience #sciencefact #funscience #demonstration #educational