Even the smalled creatures have played a part in human warfare including the Gambian pouched rat, glow worm and common garden slug. The bioluminescent glow worm was used by soldiers to help them read maps and letters in the dark trenches of WWI. Trapping them in jars, the soldiers exploited the tiny light omitting creatures to their advantage.
Also during the Great War, the common garden slug was deployed by the U.S. army in the trenches as an early warning method to the presence of mustard gas. As slugs can detect one particle per 10-12,000,000 particles of air (three times better than humans) they would indicate their discomfort to the presence of gas in enough time for the soldiers to put on their gas masks.
Whilst not directly used in warfare, the Gambian pouched rat has been trained to detect one of the most deadly bi-products of war: landmines. “We train rats to save lives” is the motto of APOPO, a Belgian organisation which trains rats to use their exceptional sense of smell for humanitarian purposes.
Trained in Tanzania and affectionately called HeroRATs, they sniff out the TNT in a landmine and scratch at the surface to indicate to their human handlers the presence of a mine. Their light weight means they don’t detonate the mines and they can cover 300 square meters of land in one hour. With 66 countries and seven territories around the world still affected to this day by landmines and other explosive bi-products of war, these rats help save the lives of thousands of people.