When you swallow food, it doesn't just drop down into your stomach. Muscles contract in a wave-like motion to move the food along through the esophagus. This muscle movement is called, peristalsis, or peristaltic waves. These peristaltic waves contract behind the food bolus pushing it along the digestive tract.
Answer:
Homology
Explanation:
Homology refers to the presence of similar or shared body structures, body parts, gene sequences, proteins, etc. among various lineages. It represents divergent evolution of these lineages from a common ancestor.
Presence of various similar structures in human and salamander reflects the fact that these two species have shared a common ancestor during their evolution. The shared ancestry between human and salamander led to the presence of various homologous body parts and identical gene sequences in them.
