Put another way, the next time you have that turkey sandwich or enjoy a chicken cutlet, you’re actually eating a dinosaur!
Dinosaurs ruled our planet from approximately 230 million to 65 million years ago when a catastrophic series of volcanic eruptions and a six-mile wide asteroid slamming into the Gulf of Mexico near modern-day Yucatan wiped out nearly 75 percent of all life on Earth. The twenty-five percent that remained evolved into every living thing that we see today, including the relatives of all contemporary plants, fish, mammals, and birds.
Dinosaurs were divided into two primary groups, the Saurischian and the Ornithischian.
The Ornithischian dinosaurs were made up of three groups, all of whom were herbivores. Stegosaurus, Triceratops, and so-called “duck-billed dinosaurs” are probably the most familiar. https://en.wikipedia.org/wiki/Ornithischia
The Saurischians were comprised of two types—the large, plant-eating four-legged sauropods like Brontosaurus and Titanosaurus and the two-legged meat-eaters called theropods such as Tyrannosaurus, Allosaurus, and the various raptors made famous in the Jurassic Park movies.
It is from the Theropods, especially the raptors like Velociraptor and Oviraptor, that modern birds evolved. We now know that all Theropods—including T-rex—had feathers. Indeed, the common ancestor of ALL dinosaurs seems to have had feathers, which means that even large sauropods and the Ornithischian dinosaurs may have had some kind of feathering. Most of these animals (especially the large ones) were non-avian dinosaurs, meaning that they didn’t fly. Over millions of years, those dinosaurs that survived the great extinction of 65 million years ago developed the ability to fly. (Some pre-extinction dinosaurs developed gliding skills but not the kind of sustained flight that we associate with post-extinction dinosaur/birds.)
ALL THEROPOD DINOSAURS had these bird-like characteristics:
3. Hollow or honey-combed light-weight bones
4. Three-toed feet (often with a claw-like "hind toe")
5. Furcula (wishbones)
6. Brooding on eggs in a nest
Here are some web resources that you can check out that really make this topic come to life:
DINOSAURS WITH FEATHERS: A great YouTube video that gives you a wonderful overview. It’s from a terrific series called SciShow. You get most of what you need to know in a little less than five minutes. It’s a crash course that makes the whole topic easy to understand: https://www.youtube.com/watch?v=msk6qabQgPA
MORE DINOSAURS WITH FEATHERS: This is a short video from the Discovery Channel that gives a nice overview of how (and why) birds evolved from larger dinosaurs.
FLYING DINOSAUR, the MICRORAPTOR. About 125 to 120 million years ago, the Microraptor made an evolutionary leap: it began to fly. This 4 minute BBC video shows you via beautiful animation what this remarkable forerunner of modern birds looked like: https://www.youtube.com/watch?v=-fyxUxGdrns
CITIPATI, a dinosaur that thrived about 80 million years ago.