People are not the first creatures to create complex hierarchical societies, the termites and ant were doing it millions of years before us.
In fact Ants specifically have attempted almost every type of society we can think of: scavenging, farming, livestock, war, slavers, nomadic, subsistence etc.
Because of their flexibility and adaptability they have been very successful and are found everywhere except Antarctica.
Because of their successes, other creatures (the social parasites) have adapted many ways to effectively live off the ants.
Some disguise themselves visually as ants, some are expert on producing the colony identification smell to be accepted, some are even other species of ants.
But one parasite stands out as truly remarkable: the Ophiocordyceps unilateralis fungus (first identified in 1865).
It was originally thought this fungus was unique, but as of 2011, 3 similar fungi more have been discovered.
Most ants are largely immune to attack by fungi because they produce a toxin called 2-phenylacetic acid, which kills most fungi and bacteria. They spread this ‘disinfectant’ as they walk around.
How ever leaf cutter ants (Atta) don’t produce this chemical disinfectant because they are fungus farmers. They don’t actually eat the leaves they cut and carry, they feed the leaves to a mound of cultivated fungus in their nest and then eat parts of the fungus. It is similar to the way people make cheese by collecting milk.
So ant of the order ‘Atta’ are vulnerable to fungal infection.
Here’s how the Ophiocordyceps unilateralis infection life cycle occurs.
An ant makes contact with a fungal spore which enters the ants body. ( infection / infiltration)
The spore releases chemicals in the ants body to take over its behavior. ( take over the brain and control actions)
The ant then attempts to climb somewhere high into a leaf or twig. ( take a prominent position)
The ant then make a death grip bite onto the leaf or twig it is standing on. ( paralyze the host with a death grip )
The ant then starves to death while the fungus grows larger inside the ants body. ( slowly kill the host, while growing larger )
The fungus grows so large it bursts out of the ant body with huge chitin horns. (out grow the host)
Often them the fungus anchors the ants body to the leaf or twin it is on. (cement dead host in place as a vehicle for propagation)
The fungal horns then produce fruiting bodies which then produce and release spores falling onto other ants. (propagation)