L. humile shows aggression not just to neighboring colonies of Argentine ants, but to any ant species. The Argentine rapidly overruns native ants in the habitats it invades. Whereas undisturbed environments might typically house upward of 10 ant species, areas that include the Argentine variety accommodate no other species.
Think of the Argentine ant as a city street tough that moves to small-town U.S., Holway said. The kid needed that big city swagger to survive on mean streets but doesn't just lose it if he moves to a mild-mannered town. The aggression and street smarts learned in an urban environment enable the transplant to establish a massive crime ring and take over the town.
What the future holds
Although Argentine ants are susceptible to some of the insecticides used in California's citrus groves, the chemicals have not made much of an impact on them. Their numbers are too large, and their supercolony spans too broad of an area. Eliminating the ants in a single household or field is temporary, and only means that it will be invaded again in the near future.
Nor is the large-scale use of pesticides the best option from an ecological standpoint. The toxic chemicals get into drinking water, not to mention rivers and oceans. Holway's lab now is looking to identify the ant's native parasites and diseases that help control L. humile in native habitats. Introducing these germs to the ants' new homes may start to keep their numbers in check.
Tsutsui himself hopes to use the new genetic data to identify how the Argentines use chemicals to lay down trails for fellow ants to follow. He also hopes to identify how L. humile learns to recognize nest mates. If Tsutsui can learn the chemical signature that identifies a colony, he can attempt to disrupt this process.
"We would be happy if, on a large scale, we can reduce the impact of these native ants so that they're only a minor pest," says Les Greenberg, an entomologist at the University of California, Riverside, who was not involved in the study. "It's probably impossible to eradicate them once they've been established."
See what we're tweeting about
8 Comments
Add CommentIt seems that importing more ants from many different colonies might help. The problem seems to be due to a single intoduction from one colony.
Reply | Report Abuse | Link to thisIt seems pretty simple,you blind the ants by covering the chemical that creates the path they follow.They get lost and the colony dies.And or create a path to death trap,and you do so without a pesticide.
Reply | Report Abuse | Link to thisHere in San Diego County's oak woodland I've witnessed an accidental elimination of the Argentine ant. Arriving at this ranch 28 years ago, I witnessed the full vigor of the species as it invaded kitchens and bathrooms. Any attempts at blockage were soon thwarted. Outside, they systematically devastated our native California Harvester ant which is the preferred prey of the endangered Coast Horned Lizard. The property owner died and I was left to determine the extent of irrigation. Having learned that summer watering encourages the oak fungus [Armillaria mellea] resulting in root or crown rot, I drastically cut back on watering. Before long it became apparent that the Argentine ant was dwindling. Each subsequent year saw more mounds of the native California Harvester ant. Today it takes a diligent search to find any Argentines. We see a few more Coast Horned Lizards now.
Reply | Report Abuse | Link to thisI did conduct one experiment on an Argentine that bears reporting. A lone ant appeared years ago on a counter top [a scout perhaps; aren't they all?]. I opened a can of sardines [before the BPA revealations] and smeared a line of the oil where the ant would find it. I had it leading to a bit of sardine. The ant found my pathway, followed it to the sardine and briefly examined the food. Then, in seconds, it lowered its abdomen to the countertop surface. Walking away, it held the abdomen pressed against the surface all the while. In those few minutes I had been shown the altruism of the species. It could have eaten its fill and then made the return trail for its mates. But instead it thought only of the colony.
Davidino...excellent observation...I hope you can get others to follow your lead....
Reply | Report Abuse | Link to thisPlease someone post something about the fireants in Florida like this...only being wishful;-)
My home was infested with these ants. If food got left on the kitchen counter overnight, in the morning it would have a column of ants leading to it from some crack in the wall.
Reply | Report Abuse | Link to thisI used a spray solution of 1 tsp. liquid dish soap per quart of water to kill the ants with easy clean up. (I believe the soap bubbles immediately suffocate the ants)
But this did not get rid of the problem.
After putting up with that for two years, I got a pack of poison bait stakes and put them all around the perimeter.
This is slow-acting poison bait that the workers carry back to the nest. It kills them all including the queens.
I haven't seen an ant here for eight years.
Unfortunately this is evolution at its finest. The more adaptable ant is crowding out the less adaptable ant. When Argentine ants meet Fire ants, I wonder which will prevail.
Reply | Report Abuse | Link to thisFood for thought:
Reply | Report Abuse | Link to thisThey want to kill the ants? Why? Is not this the age of "SAVE EVERYTHING"? Save the ants, anyone?
these ants compete locally against each other but not in a new territory.
Reply | Report Abuse | Link to thisIn a new territory there's only one gene set regardless of the size of the area so the individuals recognize each other as mates. In the "old" territory gene variants settle and procreate within the monogenomic territory and are not recognized by the original gene set. War follows and consequently the whole population is kept in check. With time there are more mutations so the original gene set becomes marginal. So introduce other argentine ants queens from somewhere else and the problem will take care of itself faster than just letting time take care of it.
As a closing note: ants make good study because they are the components of super-organisms, they can teach us a lot about robotics, networks, traffic and logisitcs. For instance how to get energy reloads in real time with no down time using each individual as a reservoir for the other. Imagine electric cars or robots getting their energy like this.