Ophiocordyceps unilateralis is a parasitic fungus that primarily infects ants, particularly the Camponotini tribe. It manipulates the behavior of its host, causing the ant to leave its colony and climb vegetation. Once at an optimal height, the ant attaches itself to a leaf or twig, where the fungus eventually kills it. After the ant dies, the fungus continues to grow, producing a stalk that emerges from the back of the ant's head. This stalk releases spores into the environment, allowing the fungus to infect other ants. This unique life cycle highlights the complex interactions between parasites and their hosts in nature.