To latch onto a deer, ticks must first pierce a thick, furry hide. Leaf-cutter ants easily gnaw through tough tropical leaves. And scorpions use their tails to inject venom into prey several times ...

In June, 2014, a man began digging into the soft red earth in the back yard of his house, on the outskirts of Kolwezi, a city in the southern Democratic Republic of the Congo. As the man later told ...