Upper Paleozoic to Lower Mesozoic Tetrapod Ichnology Revisited: Photogrammetry and Relative Depth Pattern Inferences on Functional Prevalence of Autopodia

Abstract

In recent years photogrammetry has become an essential tool in the study of tetrapod footprints. Morphological analyses of footprints are interpretative; thus, researchers should use as much information as possible in order to eventually provide an objective conclusion. In this regard, photogrammetry is an extremely helpful tool to avoid potential biases and to better present ichnological data. We review the use of this technique in several Permian and Triassic tetrapod ichnological studies, with considerations on (1) ichnotaxonomy, (2) track-trackmaker correlation, (3) locomotion and/or behavior, (4) substrate induced effects, and (5) preservation of the fossil record and heritage. Furthermore, based on the available three-dimensional (3D) data on Permian and Triassic material, we present a first qualitative interpretation of relative depth patterns and the related functional prevalence (most deeply impressed area) within footprints. We identified three main groups: (1) anamniote, captorhinomorph/parareptile tracks (medialmedian functional prevalence), (2) diapsid tracks (median functional prevalence), and (3) synapsid tracks (median-lateral functional prevalence). The use of 3D photogrammetric models brings new light to the tetrapod footprint record, helping to better understand tetrapod communities throughout the late Paleozoic (and the end-Guadalupian and end-Permian extinctions) and the tetrapod recovery during the early Mesozoic.

A captorhinid-dominated assemblage from the palaeoequatorial Permian of Menorca (Balearic Islands, western Mediterranean)

“…Photogrammetry is a technique that has recently become widespread in ichnological studies (e.g., Falkingham 2012;Mujal et al 2016Mujal et al , 2020, making it possible to collect and save information that would otherwise be lost to erosion in the case of big, unmovable rock surfaces. Moreover, it provides an alternative to the confection of artificial casts, which are sometimes hard to make in open environments that are difficult to reach.…”

Extending the footprint record of Pareiasauromorpha to the Cisuralian: earlier appearance and wider palaeobiogeography of the group

“…This latter feature is the opposite in Dimetropus (see also discussion in Mujal et al . 2020). Also, the trackway pattern is different from both Dimetropus and Amphisauropus .…”

“…2019e; Mujal et al . 2020). Also, the characteristic semi‐circular basal pad arrangement of digits well‐separated from the digit tips and forming paw‐like impressions observed in therapsid tracks does not occur in material here assigned to P. ollieri comb.…”

Evidence of large terrestrial seymouriamorphs in the lowermost Permian of the Czech Republic

“…(2020) assigned a medial–median functional prevalence to Amphisauropus tracks, together with other stem‐amniote and early amniote tracks (Mujal et al . 2020, fig 7a). However, it is clear that the manual digits III and IV and their corresponding metaphalangeal pads represent the deepest part of the manus imprint of MZM Ge 32749 (Fig.…”

“…2016; Mujal et al . 2020). The reliable spatiotemporal record of Seymouriamorpha, as documented by Amphisauropus , includes the lower–upper Permian deposits of the Czech Republic (Boskovice Basin: Pabst 1905, 1908 a , b ; Krkonoše Piedmont Basin: Geinitz 1861; Geinitz & Deichmüller 1882; Fritsch 1895, 1901; Haubold 1971), Germany (Thuringian Forest Basin: Haubold 1971, 1996; Voigt 2005; Wetterau and Saar‐Nahe Basin: Voigt 2012), Poland (Intra‐Sudetic Basin: Voigt et al .…”