Are birds really living dinosaurs?

Next time you see a pigeon or a chicken, look down at its feet. You will see rough, scaly skin, three toes in front and sharp little claws. Those feet look a lot like something from a picture book about long ago.

Maybe you have heard someone say that birds are living dinosaurs. It sounds like a joke, because a sparrow is tiny and a dinosaur is huge. So are birds really dinosaurs that are still alive today?

Millions of years ago, dinosaurs came in many shapes and sizes. Some were giant plant eaters with long necks. Others were small, quick hunters that ran on two back legs to chase bugs and lizards, and those small runners matter most for our question.

Nobody was alive back then to watch them, so scientists learn about dinosaurs from fossils, which means bones and prints that slowly turned into stone. Fossils are like a picture the rock has kept for a very long time.

In fossils of those small two-legged hunters, scientists found something surprising. Around the bones, the stone showed prints of feathers! The feathers kept those dinosaurs warm, the way a fluffy coat keeps you warm.

Scientists looked closely at the bones in those fossils, too. They found light, hollow bones, a wishbone at the chest, and feet with three toes and claws.

A chicken, a robin and an owl have all of these too, and feathers as well. Birds match those small feathered dinosaurs better than any other animal alive, and that match tells scientists the two are family.

Those small feathered dinosaurs are the ancestors of birds, which means the great, great grandparents of a family from long, long ago. Each new baby looked a tiny bit different from its parents. Over millions of years, those tiny changes added up to big ones. What do you think their feathered arms slowly turned into?

Wings! Little by little, the feathered arms of these ancestors grew longer. Wings helped them leap higher and escape hungry hunters. In time, the first birds flapped up into the air.

Then a giant rock from space crashed into the Earth, and the sky grew dark and cold for many years. All the other dinosaurs, big and small, died out, because they could not find enough food. Some small birds made it through, and their families kept on living.

That is why scientists say birds are dinosaurs, the only ones still alive today. A sparrow is not a small T. rex, though. The two belong to one big family, the way you and a faraway cousin do.

Fossils, ancestors. Small feathered dinosaurs were the ancestors of birds, and fossils show their feathers and bones, so birds are dinosaurs still living today.

Sleep softly, and the next time a bird hops by, give a little wave to a real living dinosaur.