Solitary foundation or colony fission in ants: an intraspecific study shows that worker presence and number increase colony foundation success.

Dispersal and establishment strategies are highly variable. Each strategy is associated with specific costs and benefits, and understanding which factors favour or disfavour a strategy is a key issue in ecology and evolution. Ants exhibit several strategies of establishment, i.

Experimental evidence that increased surface temperature affects bioturbation by ants.

Ants are important bioturbators that actively produce biopores and move soil particles. They could be particularly affected by global warming as they are ectotherms. Nevertheless, they can indirectly regulate their temperature, through changes in their circadian cycles and the architecture of their nests (e.

No coordination required for resources allocation during colony fission in a social insect? An individual-based model reproduces empirical patterns.

Social insects are classic examples of cooperation and coordination. For instance, laboratory studies of colony relocation, or house-hunting, have investigated how workers coordinate their efforts to swiftly move the colony to the best nesting site available while preserving colony integrity, i.e.

To have and not to have sex: When multiple evolutions of conditional use of sex elegantly solve the question in the ant genus Cataglyphis.

Organisms use an amazingly large diversity of mechanisms to pass on their genes to the next generation. Sex is ancestral in eukaryotes, where it remains the most widespread way of reproduction. By combining one's genes with those of a partner, sex entails a dilution of one's genes at each generation.

Chemical Characterization of Young Virgin Queens and Mated Egg-Laying Queens in the Ant Cataglyphis cursor: Random Forest Classification Analysis for Multivariate Datasets.

Social insects are well known for their extremely rich chemical communication, yet their sex pheromones remain poorly studied. In the thermophilic and thelytokous ant, Cataglyphis cursor, we analyzed the cuticular hydrocarbon profiles and Dufour's gland contents of queens of different age and reproductive status (sexually immature gynes, sexually mature gynes, mated and egg-laying queens) and of workers. Random forest classification analyses showed that the four groups of individuals were well separated for both chemical sources, except mature gynes that clustered with queens for cuticular hydrocarbons and with immature gynes for Dufour's gland secretions.

Social Life in Arid Environments: The Case Study of Cataglyphis Ants.

Unlike most desert-dwelling animals, Cataglyphis ants do not attempt to escape the heat; rather, they apply their impressive heat tolerance to avoid competitors and predators. This thermally defined niche has promoted a range of adaptations both at the individual and colony levels. We have also recently discovered that within the genus Cataglyphis there are incredibly diverse social systems, modes of reproduction, and dispersal, prompting the tantalizing question of whether social diversity may also be a consequence of the harsh environment within which we find these charismatic ants.

Strategies of offspring investment and dispersal in a spatially structured environment: a theoretical study using ants.

Background: Offspring investment strategies vary markedly between and within taxa, and much of this variation is thought to stem from the trade-off between offspring size and number. While producing larger offspring can increase their competitive ability, this often comes at a cost to their colonization ability. This competition-colonization trade-off (CCTO) is thought to be an important mechanism supporting coexistence of alternative strategies in a wide range of taxa.

Phenotypic plasticity and modularity allow for the production of novel mosaic phenotypes in ants.

Background: The origin of discrete novelties remains unclear. Some authors suggest that qualitative phenotypic changes may result from the reorganization of preexisting phenotypic traits during development (i.e.

Recurrent evolution of dependent colony foundation across eusocial insects.

The spectacular success of eusocial insects can be attributed to their sophisticated cooperation, yet cooperation is conspicuously absent during colony foundation when queens are alone. Selection against this solitary stage has led to a dramatically different strategy in thousands of eusocial insect species in which colonies are started by groups of nestmates and the benefits of sociality are retained continuously. Dependent colony foundation (DCF) evolved recurrently multiple times across the ants, bees, and wasps, though its prevalence in termites remains unclear.

Unequal resource allocation among colonies produced by fission in the ant Cataglyphis cursor.

How organisms allocate limited resources to reproduction is critical to their fitness. The size and number of offspring produced have been the focus of many studies. Offspring size affects survival and growth and determines offspring number in the many species where there is a trade-off between size and number.

The influence of intraspecific competition on resource allocation during dependent colony foundation in a social insect.

Organisms face a trade-off between investment in fewer, larger offspring, or more, smaller offspring. Most organisms can adjust investment through variation in the size and number of offspring in response to factors such as resource availability and competition. In some social animals, established colonies divide into groups of individuals that become autonomous, a process known as colony fission (also dependent colony foundation in social insects).

Variation in patriline reproductive success during queen production in orphaned colonies of the thelytokous ant Cataglyphis cursor.

In genetically diverse insect societies (polygynous or polyandrous queens), the production of new queens can set the ground for competition among lineages. This competition can be very intense when workers can reproduce using thelytoky as worker lineages that manage to produce new queens gain a huge benefit. Selection at the individual level might then lead to the evolution of cheating genotypes, i.

Inclusive fitness theory and eusociality.

Arising from M. A. Nowak, C.

Self-sacrifice in 'desperado' contests between relatives.

Intra-specific competition occurs in all animal species and can lead to escalated conflict. Overt fighting entails the risk of injury or death, and is usually avoided through the use of conventions or pre-fight assessments. However, overt fighting can be expected when value of the contest outweighs the value of the future, as contestants have little or nothing to lose.

Bourgeois queens and high stakes games in the ant Aphaenogaster senilis.

Background: Many animals face some form of conflict over reproductive opportunities. Queen selection in social insect colonies represents a high-stakes conflict where competition occurs among multiple queens for a few or a single reproductive role(s). The outcome of the contest is critical to the fitness of all colony individuals as most are sterile, and thus represents a conflict at multiple levels.

No actual conflict over colony inheritance despite high potential conflict in the social wasp Polistes dominulus.

Social insect societies are outstanding examples of cooperation and conflict. Individuals work together, yet seek to increase their inclusive fitness at each others' expense. One such conflict is over colony inheritance, when a queen inherits the colony following the death of the previous queen.

How many gamergates is an ant queen worth?

Ant reproductives exhibit different morphological adaptations linked to dispersal and fertility. By reviewing the literature on taxa where workers can reproduce sexually (i.e.

Direct assessment of queen quality and lack of worker suppression in a paper wasp.

Assessing a conspecific's potential is often crucial to increase one's fitness, e.g. in female choice, contests with rivals or reproductive conflicts in animal societies.

Pretender punishment induced by chemical signalling in a queenless ant.

Animal societies are stages for both conflict and cooperation. Reproduction is often monopolized by one or a few individuals who behave aggressively to prevent subordinates from reproducing (for example, naked mole-rats, wasps and ants). Here we report an unusual mechanism by which the dominant individual maintains reproductive control.