8. Horseshoe Crab

Last but not least, we have the horseshoe crab on our list of animals that have improved human medicine, too.

Every person in the world today who gets antibiotics, vaccines, or implanted medical devices such as pacemakers can have them safely thanks to the blue blood of the horseshoe crab.

Unchanged for over 200 million years, the crab’s blood gets its unusual color—blue—from copper in its special system and its unique properties that make the blood critical to modern medicine.

Researchers noticed that if the crab got wounded and the area became infected, their blood would coagulate and gunk up. And that’s exactly why horseshoe crabs are among the animals that have improved human medicine.

A protein in their blood reacts to all kinds of harmful microorganisms and can easily locate dangerous endotoxins that can be fatal. Any contamination, and experts will see the blood react.

If you liked our list of animals that have improved human medicine, you may also want to read 9 Best Therapy Dogs for Seniors Who Need Help.