A ritual is a repeated, structured sequence of actions or behaviors that alters the internal or external state of an individual, group, or environment, regardless of conscious understanding, emotional context, or symbolic meaning. Traditionally associated with gestures, words, or revered objects, rituals also occur in non-human species, such as elephant mourning or corvid object-leaving. They may be prescribed by tradition, including religious practices, and are often characterized by formalism, traditionalism, rule-governance, and performance.