Scientists know birds' eggs are different - round, potato-shaped and . People once believed eggs contained male , but that was wrong. A new says that the shape makes the bird fly better. A said birds have changed to lay eggs that have shapes. They are all different in shape - from a round owl's egg to a pointy sandpiper .
The put about 50,000 eggs from 1,400 different bird into a . They looked at the shape, length and of the eggs. They also looked at oval the eggs were. Birds with the most-oval-shaped eggs were the fliers. The team was shocked to find that egg shape affected how birds fly. Hummingbirds have the most--shaped eggs; owls have the roundest eggs; and birds have the pointiest eggs.