Discoveries, information and experiences on Ants
February 2016
Ants have a well-defined sense of hierarchy and distribution of tasks. These ants communicate via pheromones, but when the time comes to divide the tasks, violence replaces peaceful negotiations. Indeed, the ants then confront each other in duels which are in fact antenna fights.
Ant colonies are governed by a strict social order, so the members of a colony are destined to carry out specific tasks. In the case of Odontomachus ants, status is conferred based on their ability to fight. These quick antenna strokes, called quick antennations, determine which ants will have to perform the most menial tasks. Thus, the ants will fight until one of the belligerents admits defeat and decides that going in search of food is less painful than having their head pounded with antennae. The winners therefore remain in the anthill to tend the colony, while the losers must venture outside to collect food.
This type of confrontation had already been observed, but no one had measured the speed of these antenna shots. Scientists from the University of Illinois and North Carolina State University used slow-motion video to watch worker ants of the Odontomachus species compete in antennae fights. They observed four species of Odontomachus ants to measure how quickly they exchanged blows. The slowest and largest of the four species, Odontomachus Rixos, inflicts "only" 19.5 blows per second. The fastest ant in the study is Odontomachus brunneus, it is able to deliver up to 41.5 antenna strokes per second.
Although they have powerful mandibles capable of killing in an instant, these ants do not use their powerful jaws in duels. Indeed, the goal of the fight being social dominance, the ants do not seek to physically hurt a member of the colony, which is why they only use their antennae to “box”. Ants are not the only species with a habit of practicing socialized aggression. Many animals demonstrate a propensity for violence as a means of enforcing their authority. An example is lions, when they clash to determine who owns a prey. These conflicts help form a natural hierarchy that will favor the strongest members of a group, which over time increases the general fitness of the members of that group.
Source: http://sciencepost.fr/2016/02/fourmis-se-battent-duel-assert-domination-sociale/
March 2016
“In 2012, researchers showed that Pachycondyla sennaarensis venom inhibited the growth and led to the death of cancerous breast cells, without affecting non-cancerous cells. It remains to isolate the toxins responsible for this effect”
Science & Life No. 1182
February 2016
Florida worker ants have a habit of creating colonies of complex architecture, but the reason for the complexity of this architecture is still unknown.
Florida worker ants create colonies or nests that are architecturally stunning according to Walter Tschinkel. He put molten metal or plastic in abandoned underground nests to get a sense of their complexity on multiple levels. For reasons still unknown, colonies of Florida worker ants (Pogonomyrmex badius) abandon their colonies once a year and they dig up another. In a study site called the ant paradise by Tschinkel, colonies are moving about 2 to 6 meters from their former locations.
This researcher and his students from Florida State University have found no pattern that explains these moves. It is not the need to have the shadows of the trees or to be dangerously close to neighboring colonies. In addition, the new colonies resemble the old ones. The nest looks like a set of interconnected chambers that sink to have more chambers below spiral tunnels.
And the ants dig their nest at a very fast speed. The colony sends a few hundred worker ants to dig the new nest. A colony, usually consisting of 4,000 ants , can dig and move to the new colony in 7 days. During the move, we really understand the term worker ants. The latter go back and forth incessantly between the new and the old colony. These worker ants carry their queen, hundreds of larvae and young ants . They also carry the seeds and food they have collected. And these ants even move their charcoal, but it remains one more enigma as to what they do with it.
These ants scrape away pine needles and other charcoal around the openings of nests. Sometimes they collect up to 70,000 charcoals for a large colony. Researchers have offered several explanations for the usefulness of this charcoal, but they have found nothing conclusive. This could be used for insulation, to deter foreign ants, to collect rainwater or even to heat the nest. But the coal is only a small riddle compared to the other behaviors of these worker ants . Ants are a collective species. Their queen produces the young, but she has no plan in mind. This means that these worker ants perform all these tasks without a leader, a plan or even established instructions. And they can dig a new nest entirely in the dark as if there were built-in automatisms in their behaviors. Along with bees, ants are one of the most fascinating species to observe.
Source: https://actualite.housseniawriting.com
January 2016.
This article is taken from number 828 of the monthly Sciences et Avenir.
“ ENTOMOLOGY . A drug used in the treatment of bipolar disorder in humans radically alters… the role of ants within a colony. Although the relationship between behavior and DNA remains poorly identified in these insects, epigenetics, which translates into the effects of the environment on gene expression, could however be a major factor. These are the conclusions made by a team from the University of Pennsylvania (United States), echoing the great ethological debate between innate and acquired in animals. In this study, the researchers focused on carpenter ants of the genus Camponotus. These are divided into two castes: the “miners”, the workers who collect the food, and the “majors”, the soldiers who protect the anthill. The scientists injected their brains with several compounds that affect histones – proteins involved in gene regulation and activation. Depending on the alteration carried out, they then noticed that the “major” ants were starting to drill in search of food, a task that is not usually theirs! While the "minors" were more agitated than usual (see video below). This epigenetic modification therefore led to a total reprogramming of their behavior, which was moreover more marked in young subjects.
July 2012
“Nearly three years after the leak of an oil pipeline in the Crau plain (Bouches-du-Rhône), the vegetation is gradually regaining its rights. And to help it, CNRS researchers had the idea of using… ants of course! Last fall, they planted mated queens of Messor barbarus in the soil. These will give birth to thousands of workers who, by bringing seeds back to their nests, should promote the dissemination of plant species in this unique ecosystem in Europe.”
Science & Life No. 1138
Anglophone Reports on Ants:
Natural World: Empire of the Desert Ant
Captivating report on honeypot ants able to store their food in very large quantities in their incredibly expandable abdomens in order to survive during periods when food is even more scarce in desert areas.
Planet Ant – Life Inside The Colony
Among the ants, the leaf cutters are perhaps the most fascinating and evolved. This report talks about it extensively but takes the opportunity to provide valuable knowledge about ants in general. A must see.
Glands in Ants
For communication, the secretion of antibiotics, track or passport pheromones and more, ants have at least 75 different exocrine* glands!
Trail pheromones are extremely effective at minute concentrations. Thus, 1 milligram of Atta ant track pheromone would be enough to mark three times around the earth!
*secreting substances outside the body
Parasites
Some myrmecophilous beetles are able to copy the pheromones and behavior of ants during trophallaxis (food exchange). He knows how to get food from workers on demand!
Organization of Food Transport
How do ants organize themselves to transport heavy loads? Several methods exist, but a 2015 study demonstrates specific organizational mechanisms. For example, we imagine that the more ants there are, the more their collective intelligence develops. In effect, a small group of ants working to move heavy food must agree on the direction to bring it back to the nest. Unable to follow direction and pull food at the same time, ants rely on a leader to ensure direction is followed. She pulls and directs the food for the other workers to follow. But if the load is too heavy and there are too many workers to pull it, they will no longer be able to follow the leader effectively. Would small groups be the most effective?
Full article in English: http://www.popsci.com/crazy-ants-cooperate-carry-food