Middle Jurassic Tracks of Sauropod Dinosaurs in a Deep Karst Cave in France

Abstract

HAL is a multi-disciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers. L'archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d'enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.

A diverse Late Cretaceous vertebrate tracksite from the Winton Formation of Queensland, Australia

“…The borderline mild/moderate heteropody displayed in the AODF 904.S1 trackway is in sharp contrast to the pronounced heteropody seen in, for example, Occitanopodus gandi (Moreau et al, 2020). The short MP interautopodial distances and long PM interautopodial distances in the AODF 904.S1 trackway distinguish it from Titanopodus mendozensis (González Riga & Calvo, 2009;González Riga, 2011;González Riga & Tomaselli, 2019), wherein the PM interautopodial distance exceeds the length of the largest pes track, and from Oobardjidama foulkesi (Salisbury et al, 2017) and a referred trackway of Sauropodichnus giganteus (Calvo, 1999;Calvo & Mazzetta, 2004), wherein the PM interautopodial distance is almost equivalent to the length of an average-sized pes track.…”

“…Comparisons. The presence of a manual pollex ungual impression differentiates the AODF 904.S1 trackway from Occitanopodus gandi (Moreau et al, 2020), Oobardjidama foulkesi (Salisbury et al, 2017), Titanosaurimanus nana (Dalla Vecchia & Tarlao, 2000), Brontopodus plagnensis (Mazin, Hantzpergue & Olivier, 2017), Brontopodus pentadactylus (Kim & Lockley, 2012), Brontopodus birdi (Farlow, Pittman & Hawthorne, 1989), Sauropodichnus giganteus (Calvo, 1991;Calvo, 1999), Titanopodus mendozensis (González Riga & Calvo, 2009;González Riga, 2011;González Riga & Tomaselli, 2019) and Calorckosauripus lazari . By contrast, Polyonyx gomesi and Polyonyx isp.…”

“…The effective absence of distinct ungual impressions in the pes tracks of the AODF 904.S1 trackway distinguishes it from many sauropod tracks, such as Occitanopodus gandi (Moreau et al, 2020), Polyonyx gomesi (Santos, Moratalla & Royo-Torres, 2009), unnamed sauropod tracks from Niger (Ginsburg et al, 1966), unnamed sauropod tracks from Spain (Pascual Arribas et al, 2008;Pascual-Arribas & Hernández-Medrano, 2010), Brontopodus birdi (Farlow, Pittman & Hawthorne, 1989), Brontopodus pentadactylus (Kim & Lockley, 2012), and unnamed titanosaur tracks from the Anacleto Formation of Mendoza, Argentina (González Riga et al, 2015). Although the near absence of distinct digit impressions in the track walls is noteworthy, it is unclear whether or not this is a consequence of poor preservation, reduced pedal digits in the trackmaker, distortion caused by the movement of the pedal unguals during the step cycle, or a combination of some or all of these factors.…”

“…The pes tracks of the AODF 904.S1 trackway, which taper anteriorly and have flat to anteriorly concave posterior margins, differ from those of many other sauropod ichnotaxa. Several of these have anteriorly-broad, piriform pes tracks, including Polyonyx gomesi (Santos, Moratalla & Royo-Torres, 2009), Brontopodus birdi (Farlow, Pittman & Hawthorne, 1989) and Oobardjidama foulkesi (Salisbury et al, 2017), whereas other have subcircular to oval pes tracks, like Occitanopodus gandi (Moreau et al, 2020). Some of the sauropod pes tracks from the Briar Site in Arkansas (Pittman & Gillette, 1989) bear a distinct similarity to those of the AODF 904.S1 trackway, inasmuch as they are broadest posteriorly, tapered anteriorly (albeit to a lesser degree), and have posterior margins that are, at least in part, concave forwards.…”

Farm vehicles approaching weights of sauropods exceed safe mechanical limits for soil functioning

“…In other words, even the heaviest modern agricultural machinery applies only about half the weight of the heaviest sauropod per leg. We note that the difference between a sauropod footprint [the largest ever found is about 1.35 to 1.5 m 2 ( 45 , 46 )] and the footprint of a modern high-volume agricultural tire (about 1 m 2 ; SI Appendix , Table S1 ) is less than the relative difference in mass.…”