Archaeopteryx brain anatomy was reconstructed using the scan. The reconstruction showed that the regions associated with vision took up nearly one-third of the brain. Other well-developed areas involved hearing and muscle coordination. The skull scan also revealed the structure of its inner ear. The structure more closely resembles that of modern birds than the inner ear of non-avian reptiles. These characteristics taken together suggest that "Archaeopteryx" had the keen sense of hearing, balance, spatial perception, and coordination needed to fly. "Archaeopteryx" had a cerebrum-to-brain-volume ratio 78% of the way to modern birds from the condition of non-coelurosaurian dinosaurs such as "Carcharodontosaurus"
Specimens of Archaeopteryx — limiting its ability to perch on branches and implying a terrestrial or trunk-climbing lifestyle. This has been interpreted as evidence of theropod ancestry. In 1988, Gregory S. Paul claimed to have found evidence of a hyperextensible second toe, but this was not verified and accepted by other scientists until the Thermopolis specimen was described. "Until now, the feature was thought to belong only to the species' close relatives, the deinonychosaurs." The Thermopolis Specimen was assigned to "Archaeopteryx siemensii" in 2007. The specimen is considered the most complete and well preserved "Archaeopteryx" remains yet. This specimen first came to light