Some species of theropods (two-legged dinosaurs) could reach speeds of 45 kmh (28 mph), according to analysis of Early-Cretaceous trackways of theropod footprints with pace lengths of more than 2 m (6.6 feet) preserved in a trampled surface at Igea, La Rioja, Spain.
La Torre 6A tracksite map with the studied trackway in blue and the other footprints in gray. Image credit: Navarro-Lorbés et al., doi: 10.1038/s41598-021-02557-9.
“Theropod behavior and biodynamics are intriguing questions that paleontology has been trying to resolve for a long time,” said Dr. Pablo Navarro-Lorbés from the Universidad de La Rioja and his colleagues.
“The lack of extant groups with similar bipedalism has made it hard to answer some of the questions on the matter, yet theoretical biomechanical models have shed some light on the question of how fast theropods could run and what kind of movement they showed.”
“The study of dinosaur tracks can help answer some of these questions due to the very nature of tracks as a product of the interaction of these animals with the environment.”
In the new research, Dr. Navarro-Lorbés and co-authors analyzed two sets of footprints, dubbed La Torre 6A-14 and La Torre 6B-1 trackways respectively.
La Torre 6A-14 trackway contains five preserved footprints, while La Torre 6B-1 contains seven footprints.
The footprints have three toes, are longer than they are wide, and are likely to have been made by the same species of theropod, although it is not possible to determine which species that is.
“The unknown species was medium sized and very agile, potentially from the spinosaurid or carcharodontosaurid families,” the paleontologists said.
The dinosaur that created the La Torre 6A-14 trackway was bigger than the one that created 6B-1.
La Torre 6B tracksite map with the trackway 6B-01 in red and the other footprints and trackways in gray. Image credit: Navarro-Lorbés et al., doi: 10.1038/s41598-021-02557-9.
Based on the angles of and distances between the footprints, the team calculated that the theropod who made the 6A-14 tracks ran at a speed between 23.4 and 37.1 kmh (14.5 and 23.1 mph), while the 6B-1 theropod ran even faster at between 31.7 and 44.6 kmh (19.7 and 27.7 mph).
“The speeds calculated for both trackways from La Torre are among the top three speeds ever calculated for non-avian theropod tracks,” the researchers said.
“Moreover, the La Torre 6B trackway at least was printed by a dinosaur with the ability to make and control substantial speed changes while running.”
“The La Torre 6A-14 and La Torre 6B-1 trackways share with other ichnofossil localities a record of two or more running theropods. Thus, it seems that some ecological conditions were conducive to medium-sized theropods moving by running.”
The findings were published this month in the journal Scientific Reports.
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P. Navarro-Lorbés et al. 2021. Fast-running theropods tracks from the Early Cretaceous of La Rioja, Spain. Sci Rep 11, 23095; doi: 10.1038/s41598-021-02557-9
Source link: https://www.sci.news/paleontology/la-torre-footprints-10361.html
