Dr. Banta

Banta got tired of being the butt of jokes and decided to do his PhD.
While looking out for a unique subject to write his thesis on he saw a cockroach walking around.
Banta placed the cockroach on the table and cut one of its legs. And he said to him, "WALK!”
The cockroach moves forward.
Then Banta cut its second leg and shouted, "WALK!"
The cockroach manages to move forward.
Banta then cut its third leg and commanded, "WALK!" The cockroach manages to wriggle forward on one leg.
Finally Banta cut its fourth leg and shouted, "WALK !".
The poor cockroach could not move and lay helplessly on the table.
Banta repeated the same experiment with over a thousand cockroaches. And he found all results matched.
Banta was jubilant, "Now ! My thesis is ready!"
He proceeds to write down the subject: "When All Four Legs of A Cockroach Are Cut it becomes Deaf !"