Peacock
Reference: Indian peafowl
The animal everyone is actually picturing when they picture a being covered in eyes. Roughly 150–200 ocelli — Latin ocellus, “little eye” — and not one of them can see.
Scored on every axis
Two hundred eyes, zero vision
The train is not the tail. It is the upper tail coverts, feathers that overlie the true tail, and each carries an ocellus: concentric rings of structural colour produced by photonic crystals in the barbules rather than by pigment. Tilt the feather and the colour shifts, because it is interference, not paint.
The bird itself sees with two ordinary, laterally placed, tetrachromatic avian eyes — one more colour channel than a human, as covered on the vision axis. The two hundred on its back are display organs. An eyespot is an eye built to be looked at, not to look.
The same trick runs across unrelated groups: the great argus pheasant (Argusianus argus) carries rows of ocelli shaded like spheres lit from one side — Darwin singled out that “ball-and-socket” shading in The Descent of Man as the best case he knew of selection producing a deliberate optical illusion — and the peacock butterfly, owl butterflies and Io moth snap eyespots open to startle predators, a behaviour called deimatic display.
Why this bird keeps turning up in theology
Greek myth explains the ocelli directly: Hera takes the hundred eyes of the slain giant Argus Panoptes — “all-seeing” — and sets them in the peacock’s tail (Ovid, Metamorphoses I.622–723). The argus pheasant is named for the same giant.
Christian liturgy went further and built the bird into an object. The Eastern churches wave a ripidion or hexapterygon — “six-winged one” — over the Eucharistic gifts, made in the shape of a six-winged seraph with eyes on its wings; the Apostolic Constitutions (Book VIII, 4th c.) specify the deacons’ fans as thin membrane, fine cloth, or peacock feathers.
So the link between this bird and the many-eyed order is not an art-historical guess. It is a liturgical object that was literally made out of the animal.