Science in summary!
Look at carefully to picture, and try to understand what his hypothesis is about the egg.
He thinks that this egg should give birth to a pigeon. Then he assume that this egg is a pigeon egg.
But it looks like his hypothesis wrong. This egg is more like a chicken egg not pigeon, then we expect a chicken from this egg.
He should change his hypothesis, then he has to draw his conlusions based on his findings by testing his hypothesis.