Evidence of 118-million-year-old animal tracks suggests that the Catoca diamond mine in Angola was once a vastly different environment. It's likely that a shallow freshwater lake in the area served as the watering hole for a raccoon-size mammal — an extraordinary large mammal for that time — a crocodile and a dinosaur, according to the track marks. [Read full story on the ancient animal tracks]
Rocky outcrop
In 2010, geologist Vladimir Pervov found 118-million-year-old footprints belonging to prehistoric animals at the Catoca diamond mine in northeastern Angola, shown here. (Photo credit: Octávio Mateus.)
Track map
An overview of the locations of the mammal and sauropod track ways at the Catoca diamond mine in Angola. (Photo credit: Octávio Mateus.)
Trampled surface
The researchers found about 30 track marks from a mammal that lived during the time of the dinosaurs during the early Cretaceous 118 million years ago. It's likely that the mammal was going to drink at a shallow, nearby lake that no longer exists. (Photo credit: Octávio Mateus.)
High five
The mammal has five distinctive digits, with a long middle digit and a thumb that goes off to the side. The prints, which are 1 inch by 3.7 inches (2.7 by 3.2 cm), on average, suggest that the animal was about the size of a modern-day raccoon.(Photo and drawing by Vladimir Pervov.)
Crumbling print
A crumbling track mark left by the early mammal in Catoca, Angola. Unlike this animal, most mammals that lived during the early Cretaceous were only about the size of a squirrel or a mouse. (Photo credit: Marco Marzola.)
Pretty in purple
A 3-dimensional scan of the mammalian footprint. Nowadays, researchers only have a few teeth and bone fragments from these ancient mammals, making these track marks a unique find. (Photo and 3D photogrammetry by Marco Marzola.)
Walk this way
A crocodylomorph, member of a group that encompasses both current and extinct crocodiles and their relatives, left these 118-million-year-old four-digit track marks at the Catoca diamond mine, the fourth-largest diamond mine on Earth. The mine's owners agreed to suspend activity at the sector of the mine for eight months until paleontologists could study the animal prints. (Photo credit: Octávio Mateus.)
Strolling along
A photo and a drawing of the path taken by the crocodylomorph during the early Cretaceous. (Photo by Marco Marzola, drawing by Octávio Mateus.)
Dinosaur footprints
A large dinosaur, likely a sauropod, left circular footprints measuring 20 inches (51 centimeters) across. (Photo credit: Octávio Mateus.)
Skin impression
One of the dinosaur tracks left a well-preserved skin impression. This fossil gives paleontologists a good idea about the texture of the underside of the dinosaur's foot, said Marco Marzola, a paleontologist with the PaleoAngola Project, an international group of researchers that has looked for vertebrate fossils every summer in Angola for the past 10 years. (Photo credit: Octávio Mateus.)
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