The vast majority of these vertebrates move by flying. Birds have a unique cover – feathers. These consist of a special substance called keratin which gives birds extraordinary skills. Birds are extremely old animals. First birds lived 140 million years ago! These days there are approximately 8 600 different birds’ types which live and fly all around the world.
Anatomy: Their skeleton is completely bony and aerodynamically suitable for flying. Long bones are tubular and therefore extremely light. The skull is fixed to the backbone only with one vertebra just like in the Reptilia Class. A beak is created by prolonging the upper and the lower jaw. A neck is quite long and very movable. A chest bone is wide with a number of muscles, especially those responsible for flying, are fixed to it. Even the bone in the wings is attached to the chest bone. The birds’ body is covered with feathers. It is extremely light and on the other hand it is also a thermal isolation. Feather lies in two layers.
Anatomy: Their skeleton is completely bony and aerodynamically suitable for flying. Long bones are tubular and therefore extremely light. The skull is fixed to the backbone only with one vertebra just like in the Reptilia Class. A beak is created by prolonging the upper and the lower jaw. A neck is quite long and very movable. A chest bone is wide with a number of muscles, especially those responsible for flying, are fixed to it. Even the bone in the wings is attached to the chest bone. The birds’ body is covered with feathers. It is extremely light and on the other hand it is also a thermal isolation. Feather lies in two layers.
Birds
Birds
Birds
Birds
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