Night Vision
This species possesses good night or scotopic vision. Its eye includes two different kinds of ommatidium; each contains nine light sensitive cells, of which seven contain a pigment whose absorption spectrum peaks in the green part of the spectrum, but in one type the remaining two receptors have peak absorption in the blue and in the other type they have peak reception in the ultra violet. The moth therefore has the cellular prerequisites for trichromatic colour vision. Adults have been shown to be capable of making colour discriminations at night-time levels of illumination, and they sustain these discriminations despite changes in the spectral content of the incident light; that is, they show colour constancy.
Read more about this topic: Deilephila Elpenor
Famous quotes containing the words night and/or vision:
“O sovereign mistress of true melancholy,
The poisonous damp of night disponge upon me,
That life, a very rebel to my will,
May hang no longer on me. Throw my heart
Against the flint and hardness of my fault,
Which, being dried with grief, will break to powder
And finish all foul thoughts. O Antony,
Nobler than my revolt is infamous,
Forgive me in thine own particular,
But let the world rank me in register
A master-leaver and a fugitive.”
—William Shakespeare (1564–1616)
“And taken by light in her arms at long and dear last
I may without fail
Suffer the first vision that set fire to the stars.”
—Dylan Thomas (1914–1953)