There are clues to what Ice Age life was like tucked within remains from the time period. In a rare new discovery, one of those frozen time capsules — an ancient puppy — had an additional surprise waiting inside its belly.
Researchers recently discovered the 14,000-year-old mummified canine, which still has intact fur and teeth. Inside the stomach, scientists found the remains of another animal, complete with yellow fur.
DNA sequencing indicates that the Ice Age puppy ate bits of a woolly rhinoceros shortly before it died. A previous autopsy led to the conclusion that the megafauna-turned-meal was a cave lion, that idea is now overturned. The analysis was part of a larger study on woolly rhinos published this week Current Biology.
The finding may lead to new ideas about ancient dog populations, evolutionary history, and how a puppy managed to ingest a massive prehistoric animal.
Researcher Edana Lord, a Ph.D. student at the Center for Paleogenetics, tells Inverse that the woolly rhino discovery was "quite unexpected."
"As far as we know, it is very unusual to find tissue from another animal preserved in the stomach," Lord says, "although some studies have been done on plant remains from stomach contents."
Lord and her colleagues named the puppy mummy Tumat, after the Siberian site where it was discovered in 2011.
Preserving history — Genetic analysis of ancient dogs and rhinos is made possible by both permafrost and mummification.
Frozen soil in Siberia preserves ancient animals. It's "essentially like a giant freezer, keeping things cold for thousands of years," Lord explains. When an animal is buried quickly after it dies — for example, if it falls down a crevice — it can become mummified, she says.
The result is a sample both frozen in time and literally frozen, giving researchers a snapshot of life during the late Ice Age. That's how we end up with ancient dogs like Tumat and Dogor, an 18,000-year-old furry sample previously discovered by some of the same researchers. An analysis of Dogor's DNA put the pup somewhere between a wolf and a dog.
"Working on these sorts of specimens gives us a better understanding of what the ice age animals looked like [compared to their modern counterparts]," Lord says. Well-preserved samples provide more detailed evidence of diet and health, including a dog's final meal.
Specimens that maintain their fur and tissue are also easier subjects for DNA analysis, Lord says. They "tend to have much higher levels of DNA, so we can get more genetic information from them and even sequence their entire genomes," she explains.
"This allows us to ask a whole host of questions regarding their population and evolutionary history."
Tumat's diet sparks a perplexing question: How did a puppy manage to eat a woolly rhino in the first place? Lord muses that Tumat was perhaps part of a scavenging pack — ancient canids who worked together to take down megafauna.
It's also possible that someone else was involved in the hunt — like another carnivore or an early human. "It certainly is very interesting to speculate," Lord says.