Identifying pterosaur trackmakers provides critical insights into mid-Mesozoic ground invasion

Area of Science:

• Paleontology
• Vertebrate Evolution
• Ichnology (Study of Fossil Tracks)

Background:

• Fossilized tracks offer insights into extinct animals but linking tracks to specific species remains challenging.
• Pterosaur tracks are abundant but often lack clear identification of their trackmakers, limiting ecological and evolutionary studies.
• This study addresses the challenge of identifying pterosaur trackmakers to unlock the potential of trace fossils.

Purpose of the Study:

• To directly link specific pterosaur track morphotypes to distinct pterodactyloid clades using quantitative analyses and pedal anatomy.
• To expand the known biogeographic distribution of ctenochasmatoids, dsungaripterids, and neoazhdarchians.
• To test and extend macroevolutionary and ecological hypotheses using evidence from pterosaur tracks.

Main Methods:

• Quantitative analyses of fossilized track morphotypes.
• Examination of diagnostic features of pedal anatomy in pterosaurs.
• Direct comparison of track features with skeletal anatomy of specific pterosaur clades.

Main Results:

• Three distinct pterosaur track morphotypes were reliably linked to ctenochasmatoids, dsungaripterids, and neoazhdarchians.
• This linkage extends the known geographic ranges of these pterosaur clades.
• Absence of tracks before the Middle Jurassic supports arboreal habits for early pterosaurs, while track evidence shows a radiation into terrestrial niches from the Middle Jurassic onwards.

Conclusions:

• Pterosaur tracks provide crucial evidence for understanding pterosaur evolution, biogeography, and ecology.
• Derived pterodactyloid pterosaurs successfully radiated into diverse terrestrial environments throughout the Mesozoic.
• The study highlights the evolutionary adaptability and ecological significance of pterosaurs in terrestrial ecosystems.