Domination of the head in animal life as expressed in the physical structure; localization of important organs or parts in or near the head, in animal development.

concept that notes the development of a definitive head region at the anterior end of the body

localization of neural elements at the anterior end of a body plan. Example: planaria

"the tendency among animal groups for the major sense organs, mouth, and brain to be grouped together at the front (anterior) end of the body. These are usually contained in a specialized cephalic region - the head" (109).

The headward tendency of parts in phylogenetic development; the tendency of the centers to move forward, and of organs to become innervated from centers more anteriorly placed.

The concentration of sensory tissues in the anterior part of the body (head).

The evolution of a head (anterior) end with sensory structures and a highly specialized brain to process sensory input; a feature of bilaterally symmetric animals, especially the vertebrates.

Cephalization is an evolutionary trend, whereby nervous tissue, over many generations, becomes concentrated toward one end of an organism. This process eventually produces a head region with sensory organs. Cephalization is advantageous in that organisms with greater cephalization can analyze a new and potentially hazardous environment without moving their entire bodies into it.