Mate choice

For other uses, see Mate.
Mate choice is highly visible in lek mating. Here, black grouse males gather in a quagmire and the females then arrive and observe the male before choosing one.

Mate choice is one of the primary mechanisms under which evolution can occur. It is characterized by a "selective response by animals to particular stimuli" which can be observed as behavior.[1] In other words, before an animal engages with a potential mate, they first evaluate various aspects of that mate which are indicative of quality—such as the resources or phenotypes they have—and evaluate whether or not those particular trait(s) are somehow beneficial to them. The evaluation will then incur a response of some sort.[1]

These mechanisms are a part of evolutionary change because they operate in a way that causes the qualities that are desired in a mate to be more frequently passed on to each generation over time. For example, if female peacocks desire mates who have a colourful plumage, then this trait will increase in frequency over time as male peacocks with a colourful plumage will have more reproductive success.[2] Further investigation of this concept, has found that it is in fact the specific trait of blue and green colour near the eyespot that seems to increase the females likelihood of mating with a specific peacock.[3]

Mate choice is a major component of sexual selection, another being intrasexual selection. Ideas on sexual selection were first introduced in 1871, by Charles Darwin, then expanded on by Ronald Fisher in 1915. At present, there are five sub mechanisms that explain how mate choice has evolved over time. These are direct phenotypic benefits, sensory bias, the Fisherian runaway hypothesis, indicator traits and genetic compatibility.

In the majority of systems where mate choice exists, one sex tends to be competitive with their same-sex members[4] and the other sex is choosy (meaning they are selective when it comes to picking individuals to mate with). There are direct and indirect benefits of being the selective individual.[5][6][7] In most species, females are the choosy sex which discriminates among competitive males,[4] but there are several examples of reversed roles (see below). It is preferable for an individual to choose a compatible mate of the same species, in order to maintain reproductive success.[8] Other factors that can influence mate choice include pathogen stress and the major histocompatibility complex (MHC).

  1. ^ a b Bateson, Paul Patrick Gordon. "Mate Choice." Mate Choice, Cambridge University Press, 1985
  2. ^ Petrie, Marion; Halliday, Tim; Sanders, Carolyn (1991). "Peahens prefer peacocks with elaborate trains". Animal Behaviour. 41 (2): 323–331. doi:10.1016/s0003-3472(05)80484-1. S2CID 53201236.
  3. ^ Dakin, Roslyn; Montgomerie, Robert (2013). "Eye for an eyespot: How iridescent plumage ocelli influence peacock mating success". Behavioral Ecology. 24 (5): 1048–1057. doi:10.1093/beheco/art045.
  4. ^ a b Andersson, Malte (1994). Sexual Selection. Princeton University Press.[page needed]
  5. ^ Cite error: The named reference :6 was invoked but never defined (see the help page).
  6. ^ Cite error: The named reference :7 was invoked but never defined (see the help page).
  7. ^ Cite error: The named reference :8 was invoked but never defined (see the help page).
  8. ^ Halliday, T. R (1983). "The study of mate choice". In Bateson, Patrick (ed.). Mate Choice. Cambridge University Press. pp. 3–32. ISBN 978-0-521-27207-0.