Evolutionary biology: Green beard as death warrant

  title={Evolutionary biology: Green beard as death warrant},
  author={Alan Grafen},
  • A. Grafen
  • Published 6 August 1998
  • Biology
  • Nature
'Green beard' genes are theoretical constructs that cause their bearer to display a distinctive trait, fancifully named a green beard. Bearers of the gene can recognize other individuals with it and, in keeping with selfish-gene thinking, act accordingly. Now it seems that such a gene has been found in the red fire ant. In this case, if queen ants lack the gene they are executed by workers that carry it. 

Green beards in the light of indirect genetic effects

This work uses models of indirect genetic effects (IGEs) to find the minimum correlation between the signaling and altruistic trait required for the evolution of the latter, and shows that this correlation threshold depends on the strength of the interaction, as well as the costs and benefits of the altruistic behavior.

Red ants with green beards

Keller and Ross (1998) have produced what appears to be the first experimental evidence for a green beard gene in polygynous colonies (colonies with many queens) of the so called red fire ant, Solenopsis invicta.


Using a combination of simulation modeling and mathematical extension of Hamilton's rule, it is demonstrated how altruism can emerge and be sustained in a coevolutionary setting where relatedness depends on an individual's social environment and varies from one locus to another.

Étude de quelques populations structurées : processus de coalescence et abondance d’une stratégie

This paper derives the corresponding condition in the case of a phenotype space of any finite dimension obtained in the limit of a large population size by applying a perturbation method to study a mutation-selection equilibrium under weak selection.

Mechanisms: Social Recognition and Social Organisation

Social organisation in animals takes many forms. It includes assemblages of territorial animals, dominance hierarchies and social groups, among other things. The basic tenet that underlies these

Evolution of cooperation without reciprocity

Computer simulations are used to show that cooperation can arise when agents donate to others who are sufficiently similar to themselves in some arbitrary characteristic, or ‘tag’, which can be a marking, display, or other observable trait.

Effects of experience and social context on prospective caching strategies by scrub jays

It is shown that jays with prior experience of pilfering another bird's caches subsequently re-cached food in new cache sites during recovery trials, but only when they had been observed caching.

Cooperation through communication: Agent-based models and experimental results

This research looks at communication as a mean to establishing and enforcing cooperation among people, and modelled the effects of two kinds of social evaluations: namely Image (direct evaluations) and Reputation (reported evaluation).

Cooperation as a signal of genetic or phenotypic quality in female mate choice? Evidence from preferences across the menstrual cycle.

The results here consistently show that female fertility had no effect on perceptions of cooperative behaviour, and that such traits were considered more important for long-term relationships, providing strong evidence that cooperative behaviour is important in mate choice as predominantly a signal of phenotypic rather than genetic quality.

Parasitic exploitation as an engine of diversity 641

Research relevant to the relationship between parasitic exploitation, within species-polymorphism, and speciation in some of the major arenas in which such exploitation has been studied is reviewed.



Selfish genes: a green beard in the red fire ant

It is shown that BB queens initiating reproduction are killed by workers, and that it is primarily Bb rather than BB workers that are responsible for these executions.

Gestational drive and the green-bearded placenta.

  • D. Haig
  • Biology, Psychology
    Proceedings of the National Academy of Sciences of the United States of America
  • 1996
Green-beard effects have many formal similarities to systems of meiotic drive and, like them, can be a source of intragenomic conflict.

The genetic control and consequences of kin recognition by the larvae of a colonial marine invertebrate

Results of field experiments show that sibling planktonic larvae of the sessile colonial ascidian Botryllus schlosseri settle in aggregations that are much stronger than expected from dispersal distance effects alone, and this kin recognition mechanism promotes co-settlement of histocompatible individuals.

… genetics …

A possible genetic aetiology to CSVT, provides reliable risk estimates and allows accurate comparison with genetic risk in other vascular conditions is supported.

Are green beard genes outlaws?

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