| Temnothorax unifasciatus | |
|---|---|
 | |
| Temnothorax unifasciatus worker | |
Scientific classification  | |
| Kingdom: | Animalia |
| Phylum: | Arthropoda |
| Class: | Insecta |
| Order: | Hymenoptera |
| Family: | Formicidae |
| Subfamily: | Myrmicinae |
| Genus: | Temnothorax |
| Species: | T. unifasciatus |
| Binomial name | |
| Temnothorax unifasciatus (Latreille, 1798) | |
Temnothorax unifasciatus is a species of ant in the subfamily Myrmicinae.
Temnothorax unifasciatus exhibit the altruistic behavior of social withdrawal, or “altruistic self-removal” whilst on the brink of death. Dying ants will leave their nest hours or in some cases days before their death. The behavior is exhibited both in the presence of fungal infection as well as when experimentally exposed to 95% CO2, causing the ants to die in the absence of an acting pathogen. [1] This indicates that the ants are in fact behaving in an altruistic manner, rather than experiencing behavioral manipulation as a result of pathogen influence. The action is altruistic because it reduces the risk of infecting other ants in the colony. This in turn minimizes the risk of transferring the infection to kin and thus likely results in a higher inclusive fitness for the socially withdrawing individuals. [2]
Ant colonies exhibit altruistic behavior through the suppression of selfish egg-laying behavior on behalf of worker ants by means of “policing;” this is accomplished either through aggression or through direct disposal of the eggs. In a study entitled Policing Effectiveness Depends on Relatedness and Group Size, researchers found the efficacy of colony policing to improve under conditions of decreased relatedness and decreased group size. [3] The effectiveness of policing was shown to decrease in the presence of increase relatedness, because selfish behavior on behalf of kin increases the inclusive fitness of the policers, which presents a disincentive to intervene. The efficacy of policing is also influenced by the relative costs and benefits to the inclusive fitness of the actor engaging in policing behavior. In large colonies, there is less of an incentive to police selfish behavior because the costs associated with intervention outweigh the benefits to the inclusive fitness of the policer. Policing is therefore most likely to be effective in small colonies where there is low relatedness. [4]
T. unifasciatus are susceptible to being taken on as a host-species by parasitic slave-making ants which commandeer brood of other ant species to expand their colony’s own work force. Research indicates that the parasitic slave-making ants accomplish the enslavement of the ants through interference during the very early experiences of the potential host ants. T. unifasciatus are thought to use odor to identify fellow nestmates early on in development. By intervening during this stage of development, slave-making ants deceive T. uniasciatus ants into believing they are kin and thereafter do not question their presence. This is supported by a French experiment which presented a comparative analysis of parasitic slave-making species of ants and the species which are vulnerable to becoming hosts; the study found that species susceptible to become hosts were more influenced by interactions early in development than species which were not susceptible to becoming enslaved. Another difference between the species of ants that are susceptible to being enslaved as compared to non-susceptible species was that the species which were not enslaved participated in more social grooming, or allogrooming. Scientists theorize that allogrooming behavior is more common in the slave-making species because they are groomed by the ants they enslave. [5]
Kin selection is the evolutionary strategy that favours the reproductive success of an organism's relatives, even at a cost to the organism's own survival and reproduction. Kin altruism can look like altruistic behaviour whose evolution is driven by kin selection. Kin selection is an instance of inclusive fitness, which combines the number of offspring produced with the number an individual can ensure the production of by supporting others, such as siblings.
Behavioral ecology, also spelled behavioural ecology, is the study of the evolutionary basis for animal behavior due to ecological pressures. Behavioral ecology emerged from ethology after Niko Tinbergen outlined four questions to address when studying animal behaviors: What are the proximate causes, ontogeny, survival value, and phylogeny of a behavior?
Group selection is a proposed mechanism of evolution in which natural selection acts at the level of the group, instead of at the more conventional level of the individual.
In evolutionary biology, inclusive fitness is one of two metrics of evolutionary success as defined by W. D. Hamilton in 1964:
Carpenter ants are large ants indigenous to many forested parts of the world.
In biology, altruism refers to behaviour by an individual that increases the fitness of another individual while decreasing the fitness of the actor. Altruism in this sense is different from the philosophical concept of altruism, in which an action would only be called "altruistic" if it was done with the conscious intention of helping another. In the behavioural sense, there is no such requirement. As such, it is not evaluated in moral terms—it is the consequences of an action for reproductive fitness that determine whether the action is considered altruistic, not the intentions, if any, with which the action is performed.
The gyne is the primary reproductive female caste of social insects. Gynes are those destined to become queens, whereas female workers are typically barren and cannot become queens. Having a queen is what makes a "queenright" hive, nest, or colony of eusocial insects. A colony with multiple queens is said to be a polygyne form, whereas one with only one is a monogyne form.
The East African lowland honey bee is a subspecies of the western honey bee. It is native to central, southern and eastern Africa, though at the southern extreme it is replaced by the Cape honey bee. This subspecies has been determined to constitute one part of the ancestry of the Africanized bees spreading through North and South America.
Harpagoxenus sublaevis is a species of ant in the subfamily Myrmicinae. It is found in Austria, France, Germany, Italy, and Switzerland.
Polyergus breviceps is a species of ant endemic to the United States. It is a social parasite of other ants, namely of Formica gnava but also of Formica occulta and Formica argentea. Polyergus is an inquiline parasite, having lost its ability to take care of its young and themselves. "The workers do not forage for food, feed the young or the queen, or even clean up their own nest". To survive, Polyergus workers raid Formica nests to steal the pupae—which, once hatched, become workers of the mixed nest. This sort of relationship is not unique, of the approximately 8,800 species of ants, at least 200 have evolved some form of symbiotic relationship with one another. What makes Polyergus special is the way a newly mated queen can, all by herself, take over a Formica nest and start a new colony.
Temnothorax americanus is a species of slave-maker ant in the genus Temnothorax. The ants are 2–3 mm in size, and endemic to the northeastern United States and adjacent Canadian regions. They do not forage for food, but instead 'scout workers' from the colony seek out nearby host colonies of ants, steal larvae and bring them back to their own colony. A small T. americanus colony could consist of a queen, two to five workers and thirty to sixty slaves.
Formica sanguinea, or blood-red ant, is a species of facultative slave-maker ant in the genus Formica characterized by the ability to secrete formic acid. It ranges from Central and Northern Europe through Russia to Japan, China, the Korean Peninsula, Africa and also the United States. This species is coloured red and black with workers up to 7 mm long.
Eusociality, the highest level of organization of sociality, is defined by the following characteristics: cooperative brood care, overlapping generations within a colony of adults, and a division of labor into reproductive and non-reproductive groups. The division of labor creates specialized behavioral groups within an animal society which are sometimes referred to as 'castes'. Eusociality is distinguished from all other social systems because individuals of at least one caste usually lose the ability to perform at least one behavior characteristic of individuals in another caste.
Nasutitermes corniger is a species of arboreal termite that is endemic to the neotropics. It is very closely related to Nasutitermes ephratae. The species has been studied relatively intensively, particularly on Barro Colorado Island, Panama. These studies and others have shown that the termite interacts with many different organisms including a bat that roosts in its nest and various species of ants that cohabit with the termite.
Worker policing is a behavior seen in colonies of social hymenopterans whereby worker females eat or remove eggs that have been laid by other workers rather than those laid by a queen. Worker policing ensures that the offspring of the queen will predominate in the group. In certain species of bees, ants and wasps, workers or the queen may also act aggressively towards fertile workers. Worker policing has been suggested as a form of coercion to promote the evolution of altruistic behavior in eusocial insect societies.
Temnothorax is a genus of ants in the subfamily Myrmicinae. It contains more than 350 species.
Slave-making ants are brood parasites that capture broods of other ant species 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 parasite workers only concentrate on replenishing the labor force from neighboring host nests, a process called slave raiding.
Inclusive fitness in humans is the application of inclusive fitness theory to human social behaviour, relationships and cooperation.
Social immunity is any antiparasite defence mounted for the benefit of individuals other than the actor. For parasites, the frequent contact, high population density and low genetic variability makes social groups of organisms a promising target for infection: this has driven the evolution of collective and cooperative anti-parasite mechanisms that both prevent the establishment of and reduce the damage of diseases among group members. Social immune mechanisms range from the prophylactic, such as burying beetles smearing their carcasses with antimicrobials or termites fumigating their nests with naphthalene, to the active defenses seen in the imprisoning of parasitic beetles by honeybees or by the miniature 'hitchhiking' leafcutter ants which travel on larger worker's leaves to fight off parasitoid flies. Whilst many specific social immune mechanisms had been studied in relative isolation, it was not until Sylvia Cremer et al.'s 2007 paper "Social Immunity" that the topic was seriously considered. Empirical and theoretical work in social immunity continues to reveal not only new mechanisms of protection but also implications for understanding of the evolution of group living and polyandry.
Temnothorax lichtensteini is a Mediterranean species of ant in the genus Temnothorax.
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