Defecation is the final act of digestion by which organisms eliminate solid, semisolid or liquid waste material (feces) from the digestive tract via the anus. Humans usually defecate from three times a week, up to three times a day. According to the Mayo Clinic, the healthy rate of normal defecation is one bowel movement per day, less or more frequent movements probably indicate an unhealthy condition, such as lack of fiber or toxic constipation Waves of muscular contraction known as peristalsi… (More on Defecation)