From rhino horn snuff to pangolin livestock feed: A half-century of patents reveals the wildlife trade's evolution

The bright blue blood of the horseshoe crab is used around the world to detect bacterial contamination in vaccines. Synonymous with luxury, sturgeon caviar has been patented as an antidote to impotency in China. Rhino horn is used in traditional Asian medicine to treat various ailments, and is also an ingredient in 50 different recipes for snuff.