Turkeys are one of the animals in that general category that, knowing what we know now, you look at them and you're like "How could smart scientists not look at them and not see that they are obviously a form of dinosaur?"
The idea that birds are descended from dinosaurs is nearly as old as evolution itself, first being proposed by Thomas Huxley in 1868 (Origin of the Species dates from 1859).
The only reason there was a competing evolutionary theory is because it was erroneously thought that birds have a clavicle and dinosaurs don't, so instead it was proposed that birds and dinosaurs have a common ancestor, and that dinosaurs lost the clavicle. Now that they have excavated many more bones paleontologists have since discovered therapod clavicles.
Even their footprints look like a dinosaur track