The peacock butterfly has figured in research in which the role of eyespots as an anti-predator mechanism has been investigated.
The base colour of the wings is a rusty red, and at each wingtip it bears a distinctive, black, blue and yellow eyespot.
The peacock can be found in woods, fields, meadows, pastures, parks, and gardens, from lowlands up to 2,500 metres (8,200 ft) elevation.
[8] The butterfly hibernates over winter before laying its eggs in early spring, in batches of up to 400 at a time.
They are shiny black with six rows of barbed spikes and a series of white dots on each segment.
[3] The adult butterflies drink nectar from a wide variety of flowering plants, including buddleia, willows, dandelions, wild marjoram, danewort, hemp agrimony, and clover; they also use tree sap and rotten fruits.
[citation needed] This is due to their life cycle in which females are receptive only during an eclosion period, after overwintering.
[12] To find mates and defend their territory, Aglais io exhibits perching behaviour.
[14] The monandrous mating system has caused the evolution of a shorter life span in males of this species.
In polygynous butterflies, the male's reproductive success is largely dependent on life span.
Avian predators of the butterfly include blue tits, pied flycatchers and other small passerine birds.
[17] In contrast, the conspicuousness hypothesis posits that rather than recognition of the eyespots as belonging to an enemy, the conspicuous nature of the eyespots, which are typically large and bright, causes a response in the visual system of the predator that leads to avoidance of the butterfly.
When faced with avian predators like the blue tit, the peacock butterfly makes a hissing noise as well as threateningly displaying its eyespots.
[20] While hibernating in dark wintering areas, the peacock butterfly frequently encounters rodent predators such as small mice.
Instead, these rodent predators show a much stronger adverse reaction to the butterfly when it produces its auditory hissing signal.