In anatomy, the head of an animal is the rostral part (from anatomical position) that usually comprises the brain, eyes, ears, nose and mouth (all of which aid in various sensory functions, such as sight, hearing, smell, and taste). Some very simple animals may not have a head, but many bilaterally symmetric forms do. Heads develop in animals by an evolutionary trend known as cephalization. In bilaterally symmetrical animals, nerve tissues concentrate at the anterior region, forming structures responsible for information processing. Through biological evolution, sense organs and feeding structures also concentrate into the anterior region, which collectively form the head.
Read more about Head: Human Head
Famous quotes containing the word head:
“It is better to have your head in the clouds, and know where you are ... than to breathe the clearer atmosphere below them, and think that you are in paradise.”
—Henry David Thoreau (1817–1862)
“I marvel thy master hath not eaten thee for a word, for thou art not so long by the head as honorificabilitudinitatibus.”
—William Shakespeare (1564–1616)
“Standing on the bare ground,—my head bathed by the blithe air, and uplifted into infinite space,—all mean egotism vanishes. I become a transparent eye-ball; I am nothing; I see all; the currents of the Universal Being circulate through me; I am part and particle of God.”
—Ralph Waldo Emerson (1803–1882)