17. Horseshoe Crab: Medication Safety Guardian
The blue blood of horseshoe crabs contains Limulus Amebocyte Lysate (LAL), which clots when exposed to bacterial endotoxins. This property made LAL the gold standard for testing drug purity. Every injectable medication and implantable device undergoes this test. Conservation concerns about harvesting these ancient creatures led to synthetic alternatives like recombinant Factor C. Still, LAL remains essential for pharmaceutical safety in many countries.