Final answer:
Dinosaurs show many characteristics like birds and share a common ancestor. Birds evolved from theropod dinosaurs, as indicated by similarities in bone structure and the presence of the wishbone.
Step-by-step explanation:
Dinosaurs show many characteristics like birds, and many of their own among each species and their bigger "ancestors".
Paleontologists have recovered a fossil for an organism named Archaeopteryx, which has features in common with reptiles but also shows evidence of feathers, like birds. This supports the aspect of evolutionary theory that modern species share a common ancestor.
Birds evolved from theropod dinosaurs, which are a group of bipedal predators. This is highlighted by similarities between late theropod fossils and birds, specifically in the structure of the hip and wrist bones and the presence of the wishbone, formed by the fusion of the clavicles.