Theropod Foot Comparison
Another diagram for the upcoming evolution book!
The three non-avian dinosaur feet are referenced from Greg Paul diagrams; pigeon referenced from various photographs of pigeon skeletons I could find.
Two interesting points as an animal becomes more "birdlike": the hallux moves towards greater mobility, and the tarsometatarsus fuses. The tarsometatarsus of Archaeopteryx represents a unique semi-fused "transition" state between unfused and totally fused metatarsal bones.