In every dense community, human, mammal or insect, sanitation is a problem. Of all the creatures that inhabit the earth, man is probably the dirtiest, spreading his poisonous faeces everywhere and caring little about its pollutive effects. Lasius niger ants live in nests and they use the corner of their nests as common toilets, according to the journal PLOS ONE by the University of Regensburg, Germany.
Ants normally keep a very clean nest, and usually throw out dangerous rubbish, like food remains and dead bodies. This piled-up dry waste is kept for defence, as building materials, and as manure for their crops.
Lasius neglectus workers tear apart and spray acid on pupae in order to disinfect the nest. If pupae are found to carry an ant killing fungus in their bodies they are killed and eviscerated. How do they know which juveniles to kill, while the fungal infection was still in its incubation period before it had become visible or contagious? Believe it or not, according to researchers from the Institute of Science and Technology, Austria, the pupa itself communicates a find me/eat me signal, the ultimate altruistic act to save the colony.
Diseases can spread quickly among dense populations of organisms, whether they’re people living in crowded cities or groups of social insects such as ant colonies. When humans are infected with a pathogen, the immune system churns out proteins, called antibodies, that rally to the body’s defence. Some ant species use antimicrobials – chemical compounds that kill pathogens – to stop disease, according to a study at North Carolina State University published in RSOS. These antimicrobial compounds are applied by the ants to their own bodies, to those of their nest mates, and to their nests. These compounds may be acquired from antimicrobial bacteria; for example, leafcutter ants cultivate bacteria on their bodies that protect them against infection from parasites that feed on the fungus they grow as food. Other ant species harvest the ingredients from tree resin. These microbials are shared among the colony.
Ant communities have all kinds of different weapons. Often, ants will cooperate to pin down members of the other colonies, or cut them to pieces while the enemy is being held down. Ants are really quite nasty. Other ants have glands in the head, or abdomen, that exude toxic chemicals to confuse their enemies. Their tactics range from physical fighting to chemical warfare, just like it does in humans. Their wars are large scale, intense, tactical. Mark Moffett’s book, Adventures Among Ants, documents barbaric and bizarre combat strategies – the same as human ones.
130 army ant species operate like Roman armies. Moving as a massive, united front, they depend entirely on the element of surprise to overwhelm the enemy. Once the food in the new territory has been eaten the army moves on.
As in human armies, which place the young and inexperienced as foot soldiers or infantry in front, ants also assign the smallest, weakest, older ants and the cripples on the front lines. In effect, the expendables. The actual fighters are behind the lines waiting for the enemy to get tired and reduce in ranks while fighting the cheap labour. Then the large sized, mega-jawed killers move in and bite the enemy to death. And, while ants will readily die for their community, they’re also pragmatic.
“An ant would never go out of its way to save another ant,” Moffett says. “They go in to get the job done, not take care of one another.”
Slave-maker ants attack other ant colonies, captures their eggs and larvae, bring them back to their own nests and raise them as slaves to increase the worker force of their colony. After emerging in the slave-maker nest, slave workers work as if they were in their own colony, while the slavemakers only concentrate on replenishing the labour force from neighbouring nests. A colony may capture 14,000 pupae in a single season.
Most slave-raiders capture only the young, but Strongylognathus ants also enslave adult workers. Workers that emerge from eggs in the slavemakers’ nest will rear the brood, feed and groom the workers, defend the nest against aliens, and even participate in raids, including those against their original colony. In some cases, the enslaved ants rebel against their slave-maker ants, killing a large number of the slave-maker ant offspring. Thus, the slave ants protect their native colonies from further raids by slave-maker ants.
Unlike in other ant colonies, all dinosaur ants are able to reproduce. However, there’s still a single queen, surrounded by beta females. If any of the queen’s servants becomes greedy for power and decides to lay eggs and be the new queen, it’s subdued by the rest of the courtiers and pinned to the ground for up to four days until the urge subsides.
Dracula ants are the fastest animals on earth. One species, Mystrium camillae, has a pair of mandibles that snap at 90 metres a second or 320 kilometres an hour, according to a study in Royal Society of Open Science. That’s 5,000 times faster than you can blink your eye and 1,000 times faster than you can snap your fingers. Their name derives from their cannibalistic feeding habits, As adult ants are unable to process solid food, they feed prey like paralysed termites or centipedes to their larvae and then chew holes in their larvae and drink their blood.
Weaver ants, Oecophylla smaragdina, build homes out of tree leaves. Their larvae produce a thin silk which acts as the glue that sticks the leaves together.
Allomerus decemarticulatus ants of South America make tiny holes in a plant stem, hide and cover themselves with a fungus they produce themselves. When an unsuspecting insect lands on a stem full of those trap holes, the ants jump up and catch it with their mandibles. Then, they slowly drag the captive to a leaf pouch and tear it apart.
Leafcutter ants are fulltime farmers. They cut out fresh leaves with their sharp mandibles and bring them to their nests to feed a particular type of bacteria that lives with the ants. That bacteria develops into fungi to become the food source for the ants.
(To join the animal welfare movement contact gandhim@nic.in or www.peopleforanimalsindia.org)