Penguins are creatures of the sea, not of the air. Look at them under water, and you will see they are as graceful as swallows. Those “useless limbs” power the birds to higher speeds than fish can manage.
The higher viscosity of water calls for narrow wings. Similarly, contrast the shape of motorboat and airplane propellers.
Penguins are creatures of the sea, not of the air. Look at them under water, and you will see they are as graceful as swallows. Those “useless limbs” power the birds to higher speeds than fish can manage.
The higher viscosity of water calls for narrow wings. Similarly, contrast the shape of motorboat and airplane propellers.