Dinosaurs have captured people’s imagination ever since their bones and teeth were first scientifically described in 1822 by geologist and palaeontologist Gideon Mantell in England.

Dinosaur bones have taught us a great deal about these animals from the “age of dinosaurs”, the Mesozoic Era, which stretched from approximately 252 million years ago to 65 million years ago. However, there’s something especially appealing about a different kind of dinosaur fossil: their tracks, which show researchers what the animals were doing while they were alive.

Ichnology is the study of tracks and traces and, since 2008, the Cape South Coast Ichnology Project has documented more than 370 vertebrate tracksites on South Africa’s southern coast. These sites are from the Pleistocene Epoch, which stretched from approximately 2.6 million years ago to 11,700 years ago, much more recent than the Mesozoic.

We knew that this coastline contained Mesozoic sedimentary rocks, some of which include non-marine sediments that could potentially preserve dinosaur tracks. We are both familiar with dinosaur tracks from our research in Canada, so we decided to investigate the possibility of tracks in South Africa’s Western Cape.

We found some – and, once we knew what to look for, it was evident that the tracks were not rare. In a new paper published in the journal Ichnos, we describe our findings in detail, presenting evidence of tracks of sauropods (enormous plant-eating dinosaurs) and possibly ornithopods (another group of large herbivorous dinosaurs).

The tracks were found in a rugged, remote, breathtakingly spectacular coastal setting. They were made by dinosaurs in a variety of estuarine settings. Some were walking on sandy, inter-tidal channel bars. Others walked on the bottom of tidal channels, their feet sinking down into soft mud forming the bed of the channel. Other vague “squishy” structures were formed by dinosaurs wading, or even wallowing in the muddy fill of abandoned channels.

These tracks are around 140 million years old, from the very beginning of the Cretaceous period when the African and South American tectonic plates were starting to pull apart. Southern Africa has an extensive record of Mesozoic vertebrate fossils, but that record ends at around 180 million years ago in the Early Jurassic with the eruption of voluminous lava flows. To the best of our knowledge, all the southern African dinosaur tracks known until now are from the Triassic and Jurassic periods, so they pre-date these eruptions.

That means these tracks are not only the first from the Western Cape. They also appear to be the youngest – that is, the most recent – thus far reported from southern Africa.