Sexual mimicry against aggression Sexual mimicry

male ficedula hypoleuca



female/juvenile ficedula hypoleuca

sexual mimicry avoid aggression seen in birds. in bird species, males have female-like plumage colour during second year of life (sy males). these sy males sexually mature , able breed, morphology differs older, after second year (asy) males. various studies have looked delayed plumage maturation (dpm) , found dpm in sy males reduces aggression asy males. female mimicry in birds first found in european-pied flycatcher, ficedula hypoleuca. when dull-coloured male in area, mature males reduce aggressiveness , behave if intruder female. dull plumage seen in younger males, due being born later in previous spring. resemblance females benefit these young males when trying occupy territory many males present because young males can gain information , access territory not accessible them otherwise.

there big cost not looking male when comes defending territory or attracting mate. females show aggression against dull-coloured males, making harder them mate. however, dpm has benefits: mentioned above, reduces aggression older males. well, these female-looking birds able access territories, mates, , food may not available them otherwise. benefit dpm provides sy birds longer lifespan; because not have compete other males, mortality rate lower. advantage, however, benefits individuals of species have longer potential lifespan and, therefore, dpm not benefit short-lived species. known breeding threshold hypothesis, , states sy males should delay breeding if there large mortality difference between sy males attempt breed , ones not.

platysaurus broadleyi

most studies addressed dpm type of sexual mimicry, done through deception: male asy birds should not able tell females or sy males apart. however, muheter et al. (1997) found territorial males perceive dull-coloured males males show less aggression because dull-coloured plumage promotes low competitive ability. referred honest signalling , not sexual mimicry. example of sexual mimicry occurs in broadley s flat lizard, platysaurus broadleyi, males mimic females. flat lizard males tend territorial , aggressive towards other males. therefore, beneficial males mimic females in order avoid aggressive encounters , move freely through male s territory, looking mates. there 2 types of males in population; she-males, mimic females, , he-males, males. she-males can visually fool he-males believing female due female morphology. however, she-males cannot fool he-males through scent, he-males can detect difference. therefore, successful she-males avoid close contact other males, thereby reducing chances of detection through chemical signals.