If I asked you, “What is a bird?” What would you say? For most of us (at least for me) the first things that come to mind are feathers, a beak, and usually flight. Oh yes, and lays eggs. If you look out your window, go on a hike, or visit the zoo, it’s easy to recognize birds for what they are.
But what if we went back in time a few million years? It may be harder to pick out the bird from the…not bird, than you think.
Let’s say you’re picking your way through the thick undergrowth of a pine grove. You hear twittering from a branch above you, and you look up to see the tiny singer. It looks like a bird, it acts like a bird, but when it opens its beak to sing you notice tiny teeth.
Is it a bird?
Let’s try another one. Another place, another time.
You look up when you hear the sound of flapping wings above you. At first glance it looks like a bird, but then you notice those long tail feathers are not just feathers. Instead of a long train like a parrot or peacock, this fan is supported by a long tail. A closer look and you notice that this bird has claws on its wings, and a beakless snout with tiny teeth.
Is it a bird?
Let’s take a look at one more.
In another place, another time, we peak through the branches to look out into a clearing. Pecking at the undergrowth is something that looks a bit like an ostrich, or maybe an emu. Shaggy feathers, a toothless beak, and feather-duster wings all look like a big, flightless bird. But no bird has a long tail like that. That tail looks like it belongs on a lizard, if only it wasn’t covered in feathers.
Is it a bird?
At first glance, all three look very much like birds.
- The first is an early bird called Sulcavis, which lived around the same time as T-rex, in China.
- The second is Archaeopteryx. More dinosaur than bird, and from a much earlier time in Germany. It’s often reported as the first bird, but there are earlier cousins that are more bird than dinosaur.
- The third is Gallimimus. If you’ve ever seen the original Jurassic park, these are the featherless “ostrich dinosaurs” that stampede around the heroes. Fossils now tell us that these dinosaurs would look very much like emus and ostriches with tails. 🙂
So how do we know which is which? We can’t define it based on feathers, eggs, or flight. In fact, paleontologists argue quite a bit on exactly what makes something a bird or a dinosaur.
The best answer I have on this insanely complicated subject (because let’s face it, I’m no expert. I’m just a couch enthusiast 😛 )…
All birds, past and present, are dinosaurs. But not all dinosaurs are birds. 😉
Even this handsome guy. I love the thought of dinosaurs running around my yard and giving me eggs.
Quick Question: What do you think about the relationship of birds and dinosaurs? The discovery of more and more dinosaurs with feathers has turned into a rather hot topic, with passionate feelings on both sides.
Me? I think our entire natural world (and our place in it) is amazing beyond words, so I’m cool with anything the latest research has to dish out. Birds jumping on the dinosaur wagon just adds a whole new dimension of awesome. 😀
I’d love to hear your thoughts in the comments! 🙂