Head of lettuce

On this Wikipedia the language head of lettuce are at the top of the page across from the article title. Heads develop in animals by an evolutionary trend known as cephalization. In bilaterally symmetrical animals, nervous tissue concentrate at the anterior region, forming structures responsible for information processing.

The human head is an anatomical unit that consists of the skull, hyoid bone and cervical vertebrae. Sculptures of human heads are generally based on a skeletal structure that consists of a cranium, jawbone, and cheekbone. Proponents of identism believe that the mind is identical to the brain. Philosopher John Searle asserts his identist beliefs, stating “the brain is the only thing in the human head”. Mid-sagittal section of a human skull, by Leonardo da Vinci, c.

The evolution of a head is associated with the cephalization that occurred in Bilateria some 555 million years ago. A typical insect head is composed of eyes, antennae, and components of mouth. As these components differ substantially from insect to insect, they form important identification links. Eyes in the head found, in several types of insects, are in the form of a pair of compound eyes with multiple faces.