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Greetings, birdbrains!
It’s me, Dino!
Jessi asked me to visit the Fort today to talk about my favorite subject in the whole
wide world: dinosaurs!
You’ve probably heard before that dinosaurs – the giant reptiles that walked the Earth
millions of years ago – are extinct.
That means they’re not around anymore.
And it’s true that most of the dinosaurs did go extinct.
But not all of them.
65 million years ago, big changes were happening in the world.
Lots of volcanoes were erupting, and then a giant asteroid collided with Earth, in a
huge explosion!
For a long time after that, the world was very dark, then very cold, and then very hot.
With no sunlight, a lot of the plants died, so the dinosaurs that ate plants didn’t
have enough to eat, so many of them died, too.
That meant the dinosaurs that ate other dinosaurs didn’t have enough food either, and a lot
of them went extinct.
So, it was a really hard time to be a dinosaur!
But some dinosaurs were clever and talented enough to tough it out.
Because, their bodies had just the right adaptations — certain traits that helped them survive
these big changes.
The dinosaurs that survived had dinosaur babies, and soon their babies had their own little
babies, all the way down the family tree.
And the animals that came from them are still living here on Earth!
We call them … birds!
That means birds like me, Dino, are descendants of dinosaurs, and dinosaurs are my ancestors
— like my great-great-great-greatgreatgreatgreat-grandparents!
I’m part of the dinosaur family tree!
And since birds are part of the dinosaur family, I’m not just a descendant of a dinosaur
… I am one!
So the dinosaurs… live!
Now, how do we know that birds are related to dinosaurs?
Well!
We have lots of clues – specifically, from theropods, a group of two-legged dinosaurs
that also included velociraptors and Tyrannosaurus rex!
Hundreds of millions of years ago, way before the earliest birds appeared, dinosaurs were
developing lots of birdlike adaptations.
Theropod dinosaurs especially, started to have a lot of birdlike traits that would later
help birds take to the skies!
Like feathers!
Lots of dinosaurs – even dinosaurs that didn’t become birds – had feathers.
Some of these feathers were more like little hairs, which probably helped dinosaurs keep
warm.
But some types of theropods wound up with bigger, fancier feathers, and even wings.
Before there were birds, fancy feathers might have been used to keep these dinosaurs and
their eggs safe and warm, or to communicate with other dinosaurs.
But even though bigger theropods, like some kinds of tyrannosaurs, had feathers, they
couldn’t just flap their arms and fly around.
To really be able to get off the ground, you need wide, powerful wings, and a small body.
While lots of types of dinosaurs were becoming gigantic, some theropods – including those
that eventually gave rise to birds – were getting smaller.
So lots of dinosaurs already looked and moved a lot like birds.
And some of the theropod dinosaurs were becoming more like birds all the time!
Getting smaller, growing wings, and developing beaks instead of teeth.
Over millions of years, all the pieces of the bird puzzle were coming together, one
by one.
By about 150 million years ago, the earliest dino-birds were in the air.
Some of them could fly, but looked very different from the birds we know today.
And some didn’t fly, but had a lot in common with today’s birds!
Millions of years later, when that asteroid hit Earth, and the volcanoes started to erupte,
and everything started changing, some dinosaurs had a hard time surviving.
A lot of the big ones, like T-rex, were so big, they had trouble finding enough food
to eat.
But the most birdlike groups of theropods were very small – only about 1 kilogram,
or as heavy as a pineapple.
That meant it was easier for them to survive on less food and to find places to live.
And because they were so small, these early birds were also able to use their wings to
take flight!
Not only did some of these flying dinosaurs survive … they really took off!
We have more than 10,000 types of birds around today!
So the next time you see one of us feathered friends flying around, you’ll be able to
point to it and say, “Hey, look!
A dinosaur!”
Thanks for joining me, birdbrains!
Do you have questions about birds, or dinosaurs, or anything at all?
Ask a grownup to help you leave a comment below, or send us an email at kids@scishow.com.
See you next time!
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