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Remote controlled underwater vehicle with screens
Photo: Darrin Schultz / © 2021 MBARI
When Randy Prickett and Steven Haddock let their remote-controlled underwater vehicle glide over the ocean floor two years ago, the two of them stopped short.
The two deep-sea researchers from the Monterey Bay Aquarium Research Institute in the USA were actually looking for previously unknown deep-sea species.
But in front of the cameras of the small car-sized ROV (remotely operated underwater vehicle) "Doc Ricketts" suddenly an elongated, curved object lay on the ocean floor, similar to a tusk.
An unusual find.
At the time, the scientists were exploring the seabed around 3,000 meters deep, around 300 kilometers off the coast of California.
How does a tusk come from here and what animal does it come from?
Initially, the researchers only hid a small piece of the find, but only this summer did they collect the rest. As initial analyzes have shown, the discovery is even more unusual than expected. It is actually a tusk, but not an elephant's. The piece comes from a mammoth that has long since died out.
Remains of the Ice Age animals are usually found deep in the ground, and the thawing permafrost near the Arctic Circle often released them. Occasionally, remains of the prehistoric giants appeared in the North Sea. But never before in such deep waters as off the California coast. According to a report, the approximately one meter long tusk comes from a Colombian mammoth (Mammuthus columbi). It could be the oldest well-preserved mammoth tusk found in this region of North America, they say.
However, exact age information is still missing.
That is why it is now being examined by a number of different research institutions to find out when and how the tusk might have got into the deep sea - teams from the University of California and the University of Michigan are involved, among others.
It is very likely that the animal died on land, after which the remains were washed into the Pacific Ocean.
Computed tomography recordings are intended to capture the complete three-dimensional structure of the tusk.
In addition, the scientists hope for ancient DNA traces.
If they are still sufficiently preserved, sequencing could provide valuable insights into how mammoths colonized North America.
“You start to expect the unexpected when you explore the deep sea.
But I'm still amazed we met the ancient mammoth tusk, ”Haddock said.
“We are grateful to have a multidisciplinary team analyzing this remarkable specimen.
These include geochronologists, oceanographers and palaeogeneticists, ”says the researcher.
The cold, high-pressure environment of the deep sea has preserved the tusk in a unique way.
This specimen is therefore very different from others, according to the paleontologist Daniel Fisher of the University of Michigan, who specializes in mammoths and mastodons.
When the tusk could have got so deep into the sea, the aim is to find out by examining the sea sediments on the piece.
The currents on the sea floor may also provide information about the movements of the find.
joe