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:
“Unquiet wanderer
Draw the Glasnevin coverlet anew
About your head till the dust stops your ear,
The time for you to taste of that salt breath
And listen at the corners has not come;
You had enough of sorrow before death—”
—William Butler Yeats (1865–1939)
“But when his horse had put its hoof
Into a rabbit hole
He dropped upon his head and died.
His lady saw it all
And dropped and died thereon, for she
Loved him with her soul.”
—William Butler Yeats (1865–1939)
“The mountainous region of the State of Maine stretches from near the White Mountains, northeasterly one hundred and sixty miles, to the head of the Aroostook River, and is about sixty miles wide. The wild or unsettled portion is far more extensive. So that some hours only of travel in this direction will carry the curious to the verge of a primitive forest, more interesting, perhaps, on all accounts, than they would reach by going a thousand miles westward.”
—Henry David Thoreau (1817–1862)