Lek

Definition

A clustered male mating display in which multiple males aggregate in a traditional arena or swarming site to compete for female choice, without male-provided parental care or resources. Females visit solely to assess and select mates, often resulting in strong skew in male mating success. The term distinguishes this system from resource-defense or harem polygyny.

Etymology

Swedish lek, 'play, game, mating display' (originally used for bird behavior).

Example

Male goat moths (Cossidae) and certain chironomid midges form aerial leks at dusk, with females entering male swarms to select mates based on flight performance and acoustic signals.

Synonyms

• lekking site
• display arena

Related Terms

• lekking
• lek polygyny
• female choice
• Sexual selection
• lek paradox
• swarming
• lekking aggregation

Usage Notes

In entomology, 'lek' is often used more loosely than in vertebrate literature to describe any male aggregation for mating, including non-traditional swarms. Some specialists reserve the term for cases with female choice and no male parental investment; others apply it broadly to male-only mating aggregations. Contrast with 'resource-defense polygyny' (males control oviposition sites) and 'scramble competition polygamy' (no arena, widespread searching). The 'lek paradox' refers to the maintenance of genetic variance in male display traits despite strong directional selection.