The newly-discovered theropod and sauropod footprints are a part of the Late Jurassic Majala Formation, and signify the oldest dinosaur footprints reported for Chile and the western margin of the traditional supercontinent Gondwana.
Paleoartistic reconstruction of Quebrada Huatacondo throughout the Late Jurassic epoch. Picture credit score: Nahuel Vásquez.
“The Late Jurassic fossil file reveals notable disparities within the abundance and distribution of dinosaur tracksites between Laurasia and Gondwana,” stated Dr. Marko Yurac from the Unidad de Patrimonio Paleontológico and his colleagues.
“In Europe alone, a number of websites have been documented, together with these in Italy, Croatia, Poland, Spain, Switzerland, France, Germany, and Portugal.”
“Moreover, North America hosts intensive tracksites with plentiful ichnological proof.”
“In distinction, the dinosaur observe file in Gondwana is markedly extra restricted and fragmented. Notable exceptions embody track-bearing outcrops within the Excessive Atlas Mountains of Morocco.”
“Past these, ichnological proof is comparatively scarce, with only some information from Australia.
“In South America, most dinosaur tracksites are concentrated alongside the japanese margin of the continent, significantly in Brazil, Guyana, and Uruguay, with further experiences from northern areas comparable to Colombia.”
“In distinction, the western margin of South America — equivalent to the western boundary of Gondwana — has yielded Late Jurassic dinosaur tracksites completely from Chile.”
Trackway with 4 consecutive tracks of a giant tridactyl trackmaker within the Majala Formation in Chile. Picture credit score: Yurac et al., doi: 10.1186/s13358-025-00419-9.
The paleontologists recognized a complete of 5 track-bearing ranges throughout the Majala Formation within the Quebrada Huatacondo space of Chile.
The footprints have been produced by theropod and sauropod dinosaurs roughly 160 million years in the past, throughout the Late Jurassic epoch.
“Round 160 million years in the past, northern Chile skilled cycles of flooding and drought,” the researchers defined.
“Whereas the local weather was largely dry, seasonal water accumulation created ephemeral wetlands that attracted animals of all sizes — from small theropods to large carnivorous dinosaurs.”
“As dinosaurs walked throughout damp mud close to these water sources, their footprints have been imprinted within the comfortable sediment.”
“Subsequent flooding gently lined the tracks, preserving them for thousands and thousands of years.”
The Majala footprints reveal the presence of large (lengths between 51 and 52.8 cm), giant (lengths between 43.5 and 46.5 cm) and medium (lengths between 25 and 27 cm) theropod dinosaurs.
One floor has greater than 25 footprints of minute to small theropods (footprints lengths starting from 8 to 13 cm).
“These footprints represent the smallest theropod tracks recorded thus far in Chile, and presumably throughout the complete western margin of Gondwana,” the scientists stated.
One other floor represents the only stratigraphic degree exhibiting completely sauropod tracks (probably undertracks).
“On account of their poor preservation state, quantitative measurements couldn’t be obtained,” the authors stated.
“Nonetheless, evaluation of the digital mannequin allows the inference of the presence of a minimum of 9 footprints that present an alignment which may correspond to a doable trackway.”
In line with the paleontologists, their finds signify the oldest dinosaur tracks recognized from Chile and the western margin of Gondwana.
“These footprints function the first proof for reconstructing the paleoenvironmental and behavioral dynamics of dinosaurs in northern Chile throughout the Late Jurassic, reflecting episodic occupation of semi-arid floodplain and ephemeral wetland habitats,” they concluded.
The invention is reported in a paper within the Swiss Journal of Palaeontology.
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M. Yurac et al. 2025. Higher Jurassic dinosaur tracks from the Majala Formation within the Huatacondo space (Tarapacá Basin, Chile): reappraisal of recognized localities and new tracksite discoveries. Swiss J Palaeontol 144, 72; doi: 10.1186/s13358-025-00419-9
