The Law of Superposition.
The Law of Superposition states that each layer is younger than the one beneath it.
The defecation reflex involves two postive feedback loops. these loops are the stretch receptors in the rectal walls and the sacral parasympathetic system. Defecation reflex empties the rectum by peristaltic movements push fecal matter from the sigmoid colon into the rectum. Then this distension of the rectal walls stimulates stretch receptors which results in defecation.
The answer is continental rise that is what I found!!!!! I hope this helps!!!!!!