Zoology test

A young college student had stayed up all night studying for
his zoology test the next day. As he entered the classroom,
he saw ten stands with ten birds on them with a sack over
each bird and only the legs showing. He sat on the front row
because he wanted to do the best job possible.The professor
announced that the test would be to look at each of the
bird's legs and give the common name, habitat, genus,
species, etc.

The student looked at each of the birds legs. They all
looked the same to him. He began to get upset. He had stayed
up all night studying and now had to identify birds by their
legs. The more he thought about it, the madder he got.
Finally, he could stand it no longer. He went up to the
professor's desk and said, "What a stupid test! How could
anyone tell the difference between birds by looking at their
legs?"

With that he threw his test down on the professor's desk and
walked to the door. The professor was surprised. The class
was so big that he didn't know every student's name; as the
student reached the door, the professor called out, "Mister,
what's your name?"

The enraged student pulled up his pants legs and said, "You
guess, buddy! You guess!"