In the 1980s, my team sought to create a synthetic version of the gene responsible for this clotting reaction. We needed specimens to learn from, so we traveled to an estuary on Singapore’s northern coast and went into the mud to collect crabs. Oh my god, that sludge was stinky! Back in the lab, we took a few milliliters of blood, and then safely returned the animals to the water. Drug companies must drain far more blood, and many crabs die once back in the sea.