A Pennaraptorans for Your Thoughts

A realistic illustration of dinosaurs roaming a valley.

I recently learned about Penneropterans. They are not people who like to eat penne pasta! Maybe ‘opt’ refers to optics? Nope, they are not people who want to look at penne pasta, either! No, Penneropterans is a misspelling of Pennaraptora. 

What’s a Pennaraptora?

The Pennaraptora clade refers to the group of dinosaurs who developed feathers. A clade is a group of organisms that descend from a common ancestor. I learned this word from the grandson of a friend. It does roll amusingly off the tongue. The misspelling did lead me astray for a while, though. Pennaraptora is the actual term, from penna for “bird feather” and raptor for ‘thief.”

Today’s birds are believed to be descendants of dinosaurs, specifically theropods, who developed feathers. Theropods are carnivorous bipedal dinosaurs, such as Tyrannosaurus rex and the Velociraptors. Velociraptors had feathers but couldn’t fly. Their feathers are described as being pennaceous.

A pennaceous feather has a stalk or quill. The base, called a calamus, is embedded in the skin. The feather looks similar to those made by birds today. The feathers were/are made of keratin, the same protein that makes up scales and skin (and hair and fingernails).

Close-up of a white bird feather.

The strong attachment of the feather to the body suggests that the feathers could be used for flight. Discussions on the purpose of feathers suggest the feathers were first developed for warmth and attracting mates. Using the feathered wings for flight evolved later. The best early wings could do was allow the dinosaur to parachute or glide – this has been going for about 260 million years.

Pages from Elaine's new dinosaur book showing the evolution of arms to wings.

From Dinosaurs Roamed Arizona

Are there modern flying reptiles? The agamid lizard genus Draco members have bodies modified for gliding. Their extended ribs are covered with an extended membrane to create wings. It takes real feathers to attain actual flight…unless you’re a bat.

When I give my reptile talks, people often say with a sigh, “It’s a shame dinosaurs aren’t around these days.” But they are, they are flying around outside. If you’ve ever seen a roadrunner, you do not doubt that birds are related to velociraptors. To learn more about the dinosaurs of Arizona, check out my new release, Dinosaurs Roamed Arizona.

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