ecology Ecology () is the study of the relationships between living organisms, including humans, and their physical environment. Ecology considers organisms at the individual, population, community, ecosystem, and biosphere level. Ecology overl ...

, contest competition refers to a situation where available resources, such as food and mates, are utilized only by one or a few individuals, thus preventing development or reproduction of other individuals. It refers to a hypothetical situation in which several individuals stage a contest for which one eventually emerges victorious. Contest competition is the opposite of

scramble competition In ecology, scramble competition (or complete symmetric competition or exploitation competition) refers to a situation in which a resource is accessible to all competitors (that is, it is not monopolizable by an individual or group). However, sinc ...

, a situation in which available resources are shared equally among individuals. As contest competition allows the monopolization of resources, offspring will typically always be produced and survive until adulthood independent of the

population size In population genetics and population ecology, population size (usually denoted ''N'') is the number of individual organisms in a population. Population size is directly associated with amount of genetic drift, and is the underlying cause of effect ...

, resulting in stable

population dynamics Population dynamics is the type of mathematics used to model and study the size and age composition of populations as dynamical systems. History Population dynamics has traditionally been the dominant branch of mathematical biology, which has ...

. This is in stark contrast to scramble competition which can result in periodic or chaotic population dynamics. The

Beverton–Holt model The Beverton–Holt model is a classic discrete-time population model which gives the expected number ''n'' ''t''+1 (or density) of individuals in generation ''t'' + 1 as a function of the number of individuals in the previous ge ...

is often used to represent population dynamics arising from contest competition. This model, and a few other well-known population models, can be explicitly derived from individual-level processes assuming contest competition and a

random distribution In probability theory and statistics, a probability distribution is the mathematical function that gives the probabilities of occurrence of different possible outcomes for an experiment. It is a mathematical description of a random phenomenon i ...

of individuals among resources. Contest competition has been observed in a variety of species. In white-faced monkeys, ''

Cebus capucinus The Colombian white-faced capuchin (''Cebus capucinus''), also known as the Colombian white-headed capuchin or Colombian white-throated capuchin, is a medium-sized New World monkey of the family Cebidae, subfamily Cebinae. It is native to the ext ...

'', regardless of aggression, avoidance, or sex, higher ranking monkeys had higher energy intake within their group. For female '' Microcebus murinus'' groups, if the resource (fruit) could be monopolized, they would compete within their group for it. In a controlled lab experiment with three parasitic wasp species ('' Dinarmus basalis'', '' Anisopteromalus calandrae'', and '' Heterospilus prosopidis'') they found that between the first larvae in the host and the second, the larvae that would win depended on the time between them. There was also a

Nicholson–Bailey model The Nicholson–Bailey model was developed in the 1930s to describe the population dynamics of a coupled host- parasitoid system. It is named after Alexander John Nicholson and Victor Albert Bailey. Host-parasite and prey-predator systems can al ...

made to partially explain the relationship between '' Heterospilus prosopidis'' and its host ''

Callosobruchus maculatus ''Callosobruchus maculatus'' is a species of beetles known commonly as the cowpea weevil or cowpea seed beetle.Tran, B. M. D. and P. F. Credland. (1995)Consequences of inbreeding for the cowpea seed beetle, ''Callosobruchus maculatus'' (F.) (Cole ...

''. Fitness gains for the winner of the contest is not always known. For example, in mountain gorillas, ''

Gorilla beringei The eastern gorilla (''Gorilla beringei'') is a critically endangered species of the genus ''Gorilla'' and the largest living primate. At present, the species is subdivided into two subspecies. There are 3,800 eastern lowland gorillas or Grau ...

'', higher ranking females had higher average food-site resident times and higher aggression and avoidance while eating than lower ranking females. Higher ranking females have higher reproductive success, but both energy intake and the energy needed for travel to the food site do not differ among ranks. Other research in contest competition focus on what aspects are relevant for contest resolution. In a study looking at aerial wars of attrition in territorial insects, they found that the energy '' Cuterebra austeni'' got from their resources before adulthood played a role in who won. Some species have obvious gains when they win, but no morphological and/or physiological tell to determine who would win. This is the case with several species of butterflies where males hold a contest over territory. However, a study in 2010 that staged contests between male ''

Pararge aegeria The speckled wood (''Pararge aegeria'') is a butterfly found in and on the borders of woodland areas throughout much of the Palearctic realm. The species is subdivided into multiple subspecies, including ''Pararge aegeria aegeria'', ''Pararge aeg ...

'' found motivation to be a factor. The more time a male spent with a female, the more persistent they were, which increased the likelihood of the male to win the contest over the previous male holding dominance over the territory.

See also

References

Further reading