In Peru, a team of paleontologists found something astonishing in the Ocucaje desert. There were fossils (and nearly complete ones) of an extinct species of porpoises (which are close relatives to dolphins). These animals lived between 8 and 12 million years ago, around the Miocene.
They found it in Ocucaje, which is an arid part of the central coast that today is far from the sea, but in the past it was actually part of the Pacific. There is now the Pisco Formation, a time capsule that’s preserving many cetaceans and other marine species.
The skeleton is about 3.5 meters long, and it was presented in Lima by the Geological, Mining, and Metallurgical Institute of Peru (INGEMMET). Reuters reported the news, and then BBC Newsround explained it for a younger public.
According to the paleontologist Mario Urbina, the Peruvian coast was a kind of “big hotel” for marine life because of the calm waters and nutrients it has.
It’s a very important discovery , actually; it helps understand marine life, the Pacific of the past, and cetacean evolution. It shows how the ocean has been changing for millions of years.
A great discovery in a great place
The skeleton is a relative of the extant porpoises, and it has transitional features between the ancient dolphins and the modern ones. It was very well preserved: its skull, spine, and parts of the fins were there. This can allow the experts to study the way it could swim or what it ate.
The Ocucaje desert, in the south of Lima, used to be under the Pacific, and all the sediments that accumulated there saved skeletons from whales, sharks, seals, penguins, and other animals. Fossils there are highly valuable. It’s the story of an entire ecosystem. In fact, scientists are studying the animal’s teeth and inner ears to know if it would hunt alone or in troops, what prey it preferred, and how it moved on the water. This information points to the Miocene, when the weather and geography were also changing strongly and were pushing evolution in many marine species.
What happened to Ocucaje?
Now, it seems like the animal was found in a desert, but geology explains that very easily because Peru’s coast was submerged for about 45 million years. And at that time the Pisco Formation formed. Today it shows fossils, but Mario Urbina tells us that the mountains parallel to the mountains used to protect these waters, which made that place the perfect spot to get food and reproduce. That’s why he talked about a natural “big hotel.”
When the team presented the findings to the Geological, Mining, and Metallurgical Institute of Peru, they had excavated about 350 kilometers south of the capital. Reuters and BBC took care of explaining after the discovery and how these fossils help us understand the porpoises and dolphins and the change that happened in the Pacific.
But this region has many other big registers, like the one in 2024 where they announce the finding of the skull of the largest river dolphin known in the Amazon. And in 2023, a prehistoric shark in Ocucaje.
What the Ocucaje fossil teaches us today
Peru is a great place for paleontology, not a single doubt about it. And this skeleton proves, once again, that the window of that Pacific is not the same anymore.
A fossil in Ocucaje tells us how the ocean was, who lived in there, and why it mattered. It helps us reconstruct the cetaceans history and their role in the ecosystem. And understanding old ecosystems can eliminate actual ocean challenges, like global warming or the loss of so many habitats.