Scientists have developed a new method using artificial intelligence to help determine which dinosaurs created specific fossilised footprints. The approach aims to provide a more objective way of identifying track makers, an issue that has challenged palaeontologists for decades.
Why dinosaur tracks are difficult to identify
Dinosaur footprints are among the most common types of dinosaur fossils. Researchers may find a single isolated print or a dense and disordered collection of tracks, but reliably identifying which dinosaur species made a particular footprint has historically been extremely difficult.
Footprints can reveal valuable information, including the type of environment a dinosaur lived in and, when multiple tracks are present, the range of species that shared the same ecosystem.
Artificial intelligence based classification method
Researchers have now developed a method that uses artificial intelligence to assist in identifying the type of dinosaur responsible for specific tracks. The system analyses eight distinct characteristics of an individual footprint.
According to physicist Gregor Hartmann, lead author of the study published in the scientific journal Proceedings of the National Academy of Sciences, the method provides “an objective way to classify and compare tracks, reducing reliance on subjective human interpretation”.
Long standing scientific debate
Palaeontologist Steve Brusatte, a co author of the study, said that matching a footprint to its maker has been “a huge challenge” and a subject of disagreement among palaeontologists for generations.
He noted that while dinosaurs left behind many types of fossil evidence, such as bones, teeth, skin impressions and eggshells, footprints are often more abundant and can offer unique insights.
Dataset and footprint characteristics
The method was refined using an analysis of 1,974 footprint silhouettes spanning 150 million years of dinosaur history. The artificial intelligence system identified eight features that explain differences in footprint shape.
These included overall load and shape reflecting foot ground contact, load position, toe splay, how the toes connect to the foot, heel position, heel load, the relative emphasis of toes versus heel, and shape differences between the left and right sides of the footprint.
Linking tracks to dinosaur groups
Many of the analysed footprints had previously been attributed to specific dinosaur types. After identifying distinguishing features, researchers documented how these features corresponded to different dinosaur groups, helping guide the identification of future footprint discoveries.
Hartmann stressed that identifying the creator of a fossil footprint remains inherently uncertain, as footprint shape is influenced by many factors beyond the animal itself.
Factors affecting footprint appearance
According to Hartmann, footprint shape can depend on the dinosaur’s activity at the time, such as walking, running, jumping or swimming, as well as the moisture and type of ground surface, how the footprint was buried by sediment and how it was altered by erosion over millions of years.
As a result, the same dinosaur could leave footprints that look very different from one another.
Size variation and rare skeletal matches
Brusatte highlighted the wide size range of dinosaur footprints, from meat eating dinosaurs with prints similar in size to a chicken’s footprint to enormous sauropod tracks comparable in size to a bathtub.
He added that only one known case exists in which a palaeontologist discovered a dinosaur skeleton at the end of the trackway made by the same animal.
Findings from South African footprints
One notable conclusion involved seven small, three toed footprints from South Africa, dated to around 210 million years ago. The algorithm confirmed earlier scientific assessments that these tracks closely resemble bird footprints, despite being about 60 million years older than the oldest known bird fossils.
Birds evolved from small, two legged feathered dinosaurs.
Brusatte emphasised that this does not prove the tracks were made by birds. He said they may have been created by previously unknown dinosaurs ancestral to birds, or by unrelated dinosaurs that simply had bird like feet.
Source: CNA – Reuters