Bird-Hipped Dinosaurs: Evidence of Dinosaur to Bird Evolution?


Dinosaur-to-bird evolution is a famous example of macroevolutionary change that is continually heralded by its evolutionary adherents within the popular media. Stemming from this belief in the popular-level science community is that because certain types of dinosaurs are called Bird-hipped dinosaurs that it “proves” evolution from dinosaurs to birds. In this article, I address this issue.


There are two major divisions we use to classify dinosaurs based on their hip structure, being Lizard-hipped Dinosaurs (Saurischian) and Bird-hipped Dinosaurs( Ornithischian). The Lizard-hipped Dinosaurs are those like T. rex, Allosaurus, and Velociraptor, known as Theropods, and Sauropods (long necked dinosaurs), while Bird-Hipped Dinosaurs are the Ceratopsians (Triceratops), etc., basically all the dinosaurs besides the Therapods and Sauropods.

britannica dino hips (2)
“dinosaur pelvis structure”. Illustration. Encyclopædia Britannica Online. Web. 15 May. 2017.

                                            2008 Encyclopædia Britannica Inc.

First, I would like to point out a problem with the idea that the Bird-hipped dinosaurs “prove” dinosaur-to-bird evolution because of their hip structure. Modern evolutionary thought is that dinosaurs like Velociraptor evolved into birds. However, dinosaurs like Velociraptor are Therapods, Lizard-hipped dinosaurs, not Bird-hipped dinosaurs. So here we have an argument based on terminology, not real facts.

Second is their overall hip structure. Both the Bird-hipped Dinosaurs’ and Lizard-hipped Dinosaurs’ hip structure are completely different then birds’ hip structure, but they also used them slightly differently. Birds have a nearly horizontal femur, or thigh bone, made stationary by connection to the rib cage, which supports their respiratory system. This makes them walk by moving their knees instead of their hips. However, dinosaurs, like ourselves, moved with their hips. Therefore, birds are “knee-walkers” while dinosaurs were “hip-walkers”. This makes the evolution of dinosaurs to birds impossible.


In conclusion, dinosaurs’ hips and birds’ hips are different in structure and very different in use. The argument for dinosaur-to-bird evolution based on the Bird-hipped dinosaurs’ name is one based on terminology and not facts.