Dinosaurs are such a diverse group of animals that it can be a challenge to sort out who’s who. Theropoda, sauropodomorpha, ornischia…just what does it all mean? For now let’s talk about the group everyone knows and loves (but might not know it), the theropods.
For your convenience and entertainment, here are a couple of helpful Youtube videos I found. These two clips are part of a much longer course about dinosaurs, taught by paleontologist Benjamin Burger. Enjoy! 🙂
Who Were the Theropod Dinosaurs?
How Do We Group the Theropod Dinosaurs?
Warning: This one is much longer, about 30 minutes, so grab your popcorn (theropods are a ginormous group 🙂 ). If you don’t have time (because we’re all busy these days), then just scroll down for the Cliffnotes version.
Here’s the Cliffnotes version. Start from the bottom of each picture and work your way to the top.
Fun Fact: the three earliest groups here- Tawa, Coelophysidae,& Dilophosaurus, are proposed to have some sort of fur-like feathers because they are so young in the family tree. Then you don’t see very many feathers at all until Coelurosauria at the top there. Notice how we have critters like Ceratosaurus & Allosaurus here.
Since a number of critters in the middle groups have scaly skin impressions, it’s more likely that these groups were generally scaly, with limited (if any) feathering. There are one or two exceptions, but for the most part there are only bones and a few scaly skin impressions.
Coelurosauria, anything defined as more closely related to birds than Allosaurus. Pretty much everything in this group is more likely to have some sort of feathered integument. Anything from quills, hairlike filaments, or full blown assymetrical flight feathers and “peacock tails”. Yes, even T-rex, those tiny Compsognathus, and Velociraptor. 🙂
Eumaniraptora- if you saw these walking around, your first thoughts would be “bird” or “very strange bird”. Yes, Jurassic Park franchise, your “velociraptors” are supposed to be very, very birdy. We also get Archaeopteryx here, right at the base of the branch with “true birds” on it. Troodontidae are often considered a sister clade to birds. Think birds with longer tails, and teeth, and you’ve got a troodon. Possibly a bit like an owl, since they’re nocturnal, and have asymmetrical ears like owls do.
These cladograms can all be found at the University of Maryland Department of Geology website, and here’s where you can see the online lecture describing these cladograms in more detail. These cladograms are all copyright to Tom Holtz.
Bonus Question: Do you see any of your favorites here? What’s your take on the “enfluffening” of dinosaurs? I’d love to hear your answer in the comments!
PS.- I know the idea of feathered T-rex is quite the hot point for some people, but if that’s you, please remember to be kind.
I’d like to avoid the ALL CAPS AND EXCLAMATION POINTS PLEASE!!!!!1! Nobody likes to be yelled at.
Thank you for understanding. 🙂