The unexpectedly high tide may have temporarily frustrated Brusatte’s efforts to track down more ichthyosaur fossils to throw more light on these relatively poorly understood predatory marine reptiles, but the team’s discovery of large numbers of footprints more than made up for the disappointment.

They were fossil hunting in the bay just south of the Duntulm Castle ruin close to the northern tip of Skye and were about to call it a day when Brusatte and his colleague Tom Challands came across some large lumps of rock sticking up from the rocky foreshore. With the sun dipping and casting long shadows, protrusions off to one side of one of them looked very much like claws and digits. Dinosaur footprints can sometimes occur in positive relief if sediment falls into the original impression and surrounding material is eroded away.

The pair then examined some nearby depressions in the rock and realised they were negative relief footprint impressions. Further inspection revealed these occurred as multiple consecutive footprints, or trackways, on different rock layers. Challands describes the moment as “an epiphany”.

The size of the footprints - up to 70cms across - their shape, and their distribution, means they could only have been left by plant-eating sauropods. There are only a handful of other known Middle Jurassic sauropod trackways in the world, including major sites in England, Portugal, Mexico, Morocco and the US.

While fossilised dinosaur bones might look more impressive, footprints can often be more useful to palaeontologists, especially “in situ” ones that are discovered where they were left, rather than in rocks that have been detached from their original site. They can help reveal what environments the animals lived in, what they ate, how they interacted with each other, their size and weight and potentially how they changed over time.

Brusatte and Challands say they appear to have been made by primitive sauropods with narrow gauge locomotion, large thumb claws and feet with straight digits. They stress that more work will be needed to be sure of the identities of the dinosaurs that made them, but they most resemble those in the Breviparopus and Parabrontopodus groups.