Ichnology
Traces and behaviour
Reading traces of past activity
Organisms leave more than body remains. Footprints, trackways and other traces of activity record movements and interactions that bones alone do not preserve.
The method in practice
Ichnology describes these traces, their shapes, associations and relationships with sediment. Methods include recording, photography, casting and three-dimensional reconstruction. Ground deformation and preservation affect how the observed shapes are interpreted.
At Angeac and in regional comparisons
At Angeac, footprints are attributed to stegosaurs and sauropods, alongside other traces of biological activity. They record animals crossing surfaces that were later buried and preserved. Research distinguishes foot shape from deformation in the substrate, and a sequence of tracks from an unrelated set of depressions.
What this research reveals
A footprint can record an animal’s passage without identifying its species with certainty. Similarly, several nearby tracks do not automatically demonstrate a herd. These questions connect ichnology with taphonomy and environmental reconstruction.
Examining the evidence
Footprints preserved in three dimensions
Natural casts of sauropod hindfeet and forefeet preserve digits, striations and slip marks. Cast ANG 18-6529 even preserves the end of an ornithomimosaur metatarsal caught between two digit impressions.
The preserved three-dimensional shape records both the animal’s passage and ground deformation. The knife in panel C is approximately 15 centimetres long.
People and expertise
Jean-Michel Mazin contributes to studying and interpreting footprints. Field teams also record, excavate and compare the traces.
Further reading
Overview reference: Dinosaures, les géants du vignoble (2017), p. 49–50, 124–125, 204–207, 220–223.
Publications and results → · The book and its authors →
Scientific research on this topic
- 2021 · Formation of the deposit: a taphonomic synthesis (article)
- 2019 · Taphonomy of vertebrate macroremains from Angeac (doctoral thesis)
- 2018 · Trampling experiments in fine, soft sediments (article)
- 2018 · Integrative study of the Angeac bonebed (conference contribution)
- 2017 · Experimental taphonomy (chapter)
- 2016 · A trampling experiment in a wetland setting (conference contribution)
