Peristalsis is a series of wave-like muscle contractions that move food through the digestive tract. It starts in the esophagus where strong wave-like motions of the smooth muscle move balls of swallowed food to the stomach.
If two populations of birds stop interbreeding because of a difference in song patterns this would be described as behavioral isolation.
In some protists, genetic information is transferred from one cell to the next. This transfer is called Internal fertilization
Hope this helps!
-Payshence xoxo
