With its long, fluffy coat and golden hue, you might be forgiven for thinking this was some kind of exotic hamster from the Siberian wastelands.
In fact, this is the world's first "woolly mouse", a genetically engineered pioneer that was bred by scientists to have the woolly mammoth traits of shaggy fur, and the ability to withstand the cold.
The breakthrough marks a step on the path to bringing back the mammoth from extinction, and has been created by Colossal, the US de-extinction biotech company, which is also trying to resurrect the dodo.
"I was mostly surprised by how adorable they are," said Dr Beth Shapiro, chief science officer at Colossal.
"I mean, they're just mice, I guess, and mice are always a little bit cute, but they are these really adorable, golden haired, long, fluffy haired animals, and I think they're pretty spectacular."
To make the mice, scientists studied the genomes of dozens of mammoths to find out how their DNA differed from modern elephants, and worked out which genes coded for thick, fluffy coats and adaptation to cold.
Credit: Colossal Biosciences
Once the genes were found, the team then needed to narrow down the list to those that were also carried by mice.
They eventually found 10 genes that crossed over both species and related to hair length, thickness, texture and colour, as well as fat metabolism.
Scientists then made eight edits to the mouse genome, to modify seven genes. The changes included an edit in the gene FGF5, which alters hair growth cycles, leading to hair that could grow as much as three times longer than normal for the species.
Similarly, loss of function in genes FAM83G, FZD6 and TGM3 gave the mice woolly hair texture, wavy coats and curled whiskers through changes to hair follicle development and structure.
The team also chose a gene that would make the mice coats turn a golden colour, to match the mammoth mummies unearthed in the Arctic.
The mice are a test-bed to find out which gene tweaks will be needed in elephant genomes to bring back the mammoth, a task that Colossal wants to achieve by the end of the decade.
Dr Shapiro added: "You have to say, okay, so which of these genes are the ones that I would need to change if I want to take an Asian elephant cell growing in a dish in a lab and genetically alter it so that when it's turned into a mammoth or has these mammoth-like traits?
"The way that one might test this is to put those changes, a few at a time, into an animal and see what they look like.
"Here comes a problem. Elephants have a 22 month gestation, and then it takes another more than a decade to reach sexual maturity, which is not a really awesome timeline for testing scientific hypotheses about what you want to do.
"Our mammoth mice, however, have a 20 day gestation, and they are also mammals, and so even though there's 200 million years of difference between them, there's still a lot of similarities in their genomes."
She added: "This is also testing whether or not we can make multiple changes to the genome simultaneously, which is something that we're going to have to do if we want to change an elephant genome into a mammoth genome.
"There are actually eight edits in those mice because one of the genes has two different targets in it, and we get these beautiful, healthy, super cute, little woolly mice."
The team used the genomes of 59 woolly, Columbian, and steppe mammoth genomes ranging from 3,500 to 1.2 million years old and compared them to dozens of modern day elephants.
Mice were also engineered with a gene carried by mammoths called "fatty acid binding protein 2", or FABP2, which helps them store fat and put on weight, crucial for surviving in frozen climates.
Experts are hopeful that successful engineering of traits that help animals survive in colder or hotter weather could help preserve species as the climate changes.
"The Colossal woolly mouse marks a watershed moment in our de-extinction mission," said Ben Lamm, co-founder and chief executive of Colossal Biosciences.
"By engineering multiple cold-tolerant traits from mammoth evolutionary pathways into a living model species, we've proven our ability to recreate complex genetic combinations that took nature millions of years to create.
"This success brings us a step closer to our goal of bringing back the woolly mammoth."
British scientists said that the new research offered "an exciting opportunity" to test ideas about extinct animals, but warned it also raised ethical questions about mammoth revival
Commenting on the research, which was released as a pre-print ahead of publication, Dr Louise Johnson, an evolutionary biologist at the University of Reading, said: "Seeing these mice is a bit like looking back at the past, but with a highly selective telescope.
"The result does show that it is possible to genetically engineer many genes at once and still produce some live mice at the end of the process, though. The researchers have succeeded in nudging the mouse genome in the direction of a mammoth genome, which is a first.
"This technology offers an exciting opportunity to test some of our ideas about extinct organisms."
Prof Dusko Ilic, professor of stem cell science at King's College London, added: "This raises critical questions: How many elephant cows would need to undergo experimental pregnancies to give birth to a 'woolly elephant'?
"And how long would it take before the first such hybrid is born?"