Evolutionary conflict

A divergence between the outcomes favoured by selection on different individuals, replicating lineages or genetic elements. Conflict can exist without overt fighting.

Conflict among genetic elements whose transmission or expression favours different outcomes despite residence in one organism. Organismal performance alone is not the relevant fitness currency for every element.

Transmission distortion favouring an element over the Mendelian expectation. In a strict usage this acts during meiosis; broader usage also includes biased survival of gametes.

Biased transmission associated with centromere differences during asymmetric meiosis, where only some meiotic products contribute to the next generation.

A modifier reducing a driver’s transmission advantage or harmful consequences. Selection depends on linkage, background and the costs of suppression.

Deviation in inherited allele proportions from the Mendelian expectation. Embryonic viability selection can also distort offspring counts and must be separated from gametic transmission bias.

A genetic element that can spread through a transmission or replication advantage even when it imposes costs on the organism carrying it.

Differences in the outcomes favoured by selection on males and females, for example over mating, fertilization or parental care. Shared benefits from reproduction do not imply identical optima.

A seminal protein studied in Drosophila melanogaster whose transfer affects female physiology and behaviour. Its evolutionary costs and benefits depend on mating regime and measured time horizon.

Conflict mediated by interacting traits encoded at different loci in the sexes, including manipulative traits and resistance.

Different sex-specific optima for a trait influenced by shared genetic variation. Sex-limited expression can reduce the conflict without requiring all genetic effects to become independent.

Reciprocal evolutionary change in traits of the sexes arising through opposed reproductive effects. Correlated morphologies alone need not prove historical reciprocal selection.

Competition among offspring over resources, care or other opportunities. It can interact with parent-offspring conflict by redistributing a fixed supply and altering total parental provisioning.

A decline in the number of surviving offspring within a brood, often associated with limited provisioning. The occurrence of brood reduction alone does not establish an adaptive parental or offspring strategy.

Killing of a sibling, whose ecological and evolutionary explanations depend on resource limitation, asymmetry and the consequences for survivors and parents.

Contingent communication among siblings about their willingness to contest a resource, potentially reducing unnecessary competitive costs.

Differences between parental and offspring strategies favoured by selection, including allocation and duration of care. Costs imposed on other offspring have different weights in the parties’ fitness accounts.

Behaviour or control that reduces the success of selfish actions by other group members. Selection on policing depends on its costs, effects on productivity and genetic or direct benefits to the policing party.

Suppression of worker reproduction by other workers, including discriminatory removal of worker-laid eggs. Genetic incentives and effects on colony productivity can both matter.

Conditional reduction of benefits to a partner that supplies a poor service, potentially changing the returns to exploitation. An immediate physiological response and its evolutionary explanation should be distinguished.