gonna look into it too but what were some specific adaptations of modern day dinosaurs from their dinosaur ancestors that can be seen?
I know their lungs would obviously have to have some shifting going on. And from what we can tell, the beaks also was another change over time
It is probably hard to a hundred percent tell because of not having all the organs. but still, with the knowledge we know, what some of these organs may have been like off of skeletal shapes
but yeah, just different adaptations from around the start of the transition into non avian to avian dinosaurs (with the oldest known fossils)
well, for one, the fact that they have legs directly underneath their bodies. that's just dinosaur legs.
they also have four toes, which, theropod dinosaurs also only had four toes - the fourth one was often off the ground, which many living birds share today, having three toes on the ground. Those toes end in claws in most birds, just like in their nonavian ancestors.
Feathers themselves are a dinosaur trait. Well, an Ornithodira trait. But they were common in dinosaurs. Same with warmbloodedness.
Saurischia is where we see the evolution of the avian lung system.
We see the gradual reduction of the hand into the bird hand from the start of Theropoda through to Euornithes
Beaks evolved multiple times in multiple clades. The beak that is homologous with bird beaks started in Euornithes - so, excluding opposite birds/Enantiornithines.
the complex vocal organs seem to be a dinosaur thing based on that ankylosaur larynx specimen
wins start showing up in maniraptoriformes and are fully formed by paraves, so Gallimimus and Deinocheirus had baby wings and Velociraptor had full wings
Flight shows up in Paraves
so,,, yeah. technically everything birdie is dinosaur, but those are the things that show up before Neornithes. Only the full beak is a Neornithine-only trait.