Crazy Ants Dominate Fire Ants by Detoxifying their Venom [VIDEO]

Last year the invasive and ecologically dominant 'crazy ants' made it to the headlines for attacking fire ants colonies in areas across South-eastern U.S. A new study reveals the strategy that crazy ants adopt to take over the fire ants and other arthropods.

According to the researchers at the University of Texas at Austin, the invasive crazy ants displace the fire ants by secreting a compound that neutralizes the venom injected by the fire ants' intensely painful stings. This is one of the earliest known cases of an insect with the super ability to detoxify the venom of another insect.

Fire ants, known for their painful stings, often succeed in dominating over other ant species by dabbing them with their powerful and fatal venom that is two to three times more toxic than DDT on a per weight basis. Commonly found in house yards and open grounds they form mounds and sting a person only when one steps on their mound. Crazy ants, on the other hand, invade homes, live in empty spaces and walls and even damage electrical equipment.

This is the first time a study describes the detoxification process that crazy ants adopt against fire ant venom. Crazy ants, with the official common name 'Tawny crazy ants', combat the venom with formic acid, which is secreted from a special gland located near the abdomen. They transfer the acid to the mouth and smear it on their body.

According to the news release, this formic acid, makes the tawny crazy ants nearly invincible in the battle with fire ants that mostly takes place over nesting sites and food resources.

"The crazy ants charged into the fire ants, spraying venom," said Ed LeBrun, a research associate with the Texas invasive species research program at the Brackenridge Field Laboratory in UT Austin's College of Natural Sciences. "When the crazy ants were dabbed with fire ant venom, they would go off and do this odd behavior where they would curl up their gaster [an ant's modified abdomen] and touch their mouths."

To check this, the researchers conducted an experiment in the lab. They sealed the glands of the crazy ants with nail polish and later put them in vials along with the red fire ants. During a battle with the fire ants, the crazy ants with sealed glands failed to apply the detoxifying compound to themselves due to which half of the crazy ants dabbed with fire ants venom died. On the other hand, the control group consisting of crazy ants with unsealed glands had a 98 percent survival rate.

 The researchers have no clue  how the formic acid turns the fire ants' venom nontoxic, but they assume that the acid prevents the venom from penetrating into the outer layers of the crazy ant's exoskeleton.

"As this plays out, unless something new and different happens, crazy ants are going to displace fire ants from much of the southeastern U.S. and become the new ecologically dominant invasive ant species," said LeBrun.

Crazy ants are slowly displacing arthropods like spiders, centipedes, insects and crustaceans and it is bound to have a dramatic effect on the ecosystem by lowering the availability of food resources for birds, reptiles and other animals.

Apart from human intervention what can curb the growing crazy ant population are natural factors like arid soils and severe freezes that make the conditions harsh for them to survive.

Crazy ants were discovered in 2002 in a suburb of Houston and since then they have established themselves in 21 counties in Texas and 20 counties of Florida. In 2012, they were formally identified as Nylanderia fulva, native to northern Argentina and Southern Brazil. They are also referred as Rasberry crazy ants.

The finding was published in the journal Science Express.