Fossil footprints reveal how dinosaur ancestors gradually shifted from sprawling to upright walking

The discovery of ancient footprints in the Dolomites, Italy, provides significant insights into the evolution of dinosaur ancestors' locomotion. The finding, led by Dr. Lorenzo Marchetti, reveals that early archosauriforms, a group that includes dinosaurs and their close relatives, transitioned from sprawling to upright walking over time. This shift is a crucial aspect of their evolution, as it would have allowed these animals to move more efficiently and potentially access new habitats and resources.

The footprints, identified as Pachychirotherium gardenaensis, date back to the early Triassic period, around 245 million years ago. This makes them some of the earliest known examples of archosauriform footprints. The fact that these footprints show a more sprawling gait, while later footprints from the same group exhibit more upright walking, suggests a gradual transition over millions of years. This gradualism is consistent with the fossil record, which often shows incremental changes in species over time.

As researchers continue to study these and other fossil footprints, they will likely gain a better understanding of the evolution of locomotion in archosauriforms. Key questions to watch next include: How did this transition to upright walking influence the evolution of other characteristics, such as body size and brain development? Did different groups of archosauriforms develop upright walking independently, or was it a single innovation that spread throughout the group? Further study of fossil footprints and other evidence will help scientists reconstruct the history of these fascinating creatures.

Originally reported by phys.org. LearningWire adds analysis for science & discovery readers.