Altricial, meaning "requiring nourishment", refers to a pattern of growth and development in organisms which are incapable of moving around on their own soon after hatching or being born. The word is derived from the Latin root alere meaning "to nurse, to rear, or to nourish" and refers to the need for young to be fed and taken care of for a long duration. Species whose young are immediately or quickly mobile are known as precocial.