Compare the two theories regarding the evolution of dinosaurs and then consider the cladogram above. Although the two theories differ on the evolutionary path of dinosaurs, they agree that

they agree that dinosaurs, reptiles, and birds had belong to common ancestor.

Explanation:

The reptilians initially emerged before the dinosaurs, but after they never appeared less, the dinosaurs managed to take up the top niches in the food chain. On the other hand, the birds are in fact an evolutionary product of dinosaur diversification. The birds evolved from small bipedal dinosaurs that began to take on a new way of life and appearance in the course of time.

The dinosaurs have not evolved as a separate phylum that does not have close relationships with other animals, but rather shares a common ancestor with reptiles and bird likes.