How Horseshoe Crab Blood Saves Millions of Lives

“You don’t survive for 450 million years without learning a trick or two.
In the case of horseshoe crabs, one of those is developing blood with
remarkable antibacterial properties. Humans haven’t been around nearly
as long, but we learn fast, including how to harness those properties in
ways that save our lives, but aren’t so great for the crabs.”