Genetic polymorphism for chemical tags in leaf-cutting ants
Lead Research Organisation:
University of Leeds
Department Name: Inst of Integrative & Comparative Biolog
Abstract
Although social groups most obviously exhibit cooperation, they are also often the scene of conflict. Unless group members are clones, their reproductive interests will differ and individuals may benefit by exploiting the cooperative efforts of other group members. Cheating is therefore predicted to arise in all non-clonal systems, but is not thought to occur in one of the classic examples of cooperation, the rearing of brood by social insects. Adult workers would benefit by preferentially rearing brood to which they are more related into reproductive queens rather than sterile workers. Although the chemical recognition tags (cuticular hydrocarbons) are well known to differ between colonies, they are not thought to differ between genotypes. Workers are thus believed to lack the necessary information to distinguish larvae genotypically and so are unable to act nepotistically when rearing brood. Only two studies have tested this prediction, however, with one finding genetic polymorphism for chemical tags and the other not. The project will test the prediction in a leaf-cutting ant system that facilitates the detection of genetic polymorphism and which has an intriguing genotypic variation in caste propensity, with certain 'royal' genotypes that tend to develop into queens. By comparing the chemical tags of both adults and larvae of different genotypes, the project will test the evolutionary theory that there is not the necessary genetic polymorphism for nepotism to occur. It will also compare the tags of royal and normal genotypes to determine if the former have any special tag that tells nursing workers that they are royalty.
People |
ORCID iD |
William Hughes (Principal Investigator) |
Publications
Nehring V
(2011)
Kin-informative recognition cues in ants.
in Proceedings. Biological sciences
Description | Although social groups most obviously exhibit cooperation, the reproductive interests of group members will differ and cheating is therefore predicted to arise. However, such cheating is not thought to occur though in one of the classic examples of cooperation, brood rearing by social insects. This is believed to be because adult workers are unable to distinguish the genotypes of larvae, and thus unable to nepotistically bias larval caste destiny. Social insects are well known for their ability to distinguish nestmates based upon complex profiles of cuticular hydrocarbons (CHCs), but these CHC tags are believed to be indistinguishable between genotypes. In addition, the occurrence of nepotism based on genotypically distinct recognition tags should in theory select for the erosion of the very polymorphism upon which the nepotism is based. This project used polyandrous leaf-cutting ants to investigate whether CHC tags are genetically polymorphic, and thus whether the information necessary for nepotism is present. Within all of the colonies we examined, we found that at least some patrilines differed significantly from one another in the composition of their cuticular hydrocarbons. As individuals from different patrilines within a colony share the same maternal genotype on average, maternal cues and environmental rearing conditions, they differ only in their paternal genotype and differences between patrilines are therefore evidence of genetic polymorphism. Theory predicts that genetic polymorphism for recognition cues should not be present within social insect colonies, but our results demonstrate that it is. |
Exploitation Route | None This was fundamental 'blue skies' science without potential exploitation |
Sectors | Agriculture, Food and Drink |
Description | International collaboration with Copenhagen |
Organisation | University of Copenhagen |
Country | Denmark |
Sector | Academic/University |
PI Contribution | We contributed expertise and resources to the collaboration, and provided training to researchers at the partner organisation |
Collaborator Contribution | The partner contributed expertise and resources, and provided training to members of my research team. |
Impact | Nehring, V., Evison, S.E.F., Santorelli, L.A., D'Ettorre, P. & Hughes, W.O.H. 2011. Kin-informative recognition cues in ants. Proc R Soc Lond B 278:1942-1948. Frost, C.L., Fernandez-Marin, H., Smith, J.E. & Hughes, W.O.H. 2010. Multiple gains and losses of Wolbachia symbionts across a tribe of fungus-growing ants. Mol Ecol 19:4077-4085 |
Start Year | 2007 |
Description | International collaboration with D'Ettorre |
Organisation | International Fine Particles Research Institute Ifpri |
Country | United States |
Sector | Charity/Non Profit |
PI Contribution | Contributed expertise and resources, and provided training to researchers in the partner organisation |
Collaborator Contribution | Contributed expertise and provided training to members of my research team |
Impact | Nehring et al. 2011 Proc R Soc Lond B paper |
Start Year | 2009 |
Description | Discovery Zone exhibit |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | Local |
Primary Audience | Schools |
Results and Impact | Discovery Zone exhibit None |
Year(s) Of Engagement Activity | 2009 |