While they won’t be pulling Santa’s sleigh anytime soon, Svalbard reindeer (Rangifer tarandus platyrhynchus) objectively could win a North Pole cuteness contest. This subspecies of reindeer is only found on Norway’s Svalbard archipelago and stands at roughly five-feet long and three-feet tall and about half the size of other reindeer. “They are actually quite morphologically unique from other reindeer. They’re shorter, they’re fatter, they’re hairier,” Samantha Paige Dwinnell, an ecologist who studies this unique subspecies in Svalbard, tells Popular Science. “Their hair is twice as long and they are the fattest of the deer family in the world.” Here are some more things to know about Earth’s smallest reindeer. Get the Popular Science newsletter Breakthroughs, discoveries, and DIY tips sent every weekday. Email address Sign up Thank you! By signing up you agree to our Terms of Service and Privacy Policy. Svalbard is like their own little paradise Svalbard reindeer have been living on this archipelago for 5,000 years. Over that time, they have been very isolated from other populations of reindeer on mainland Europe. “They don’t have any real natural predators and they evolved in an ecosystem without real predators,” says Dwinnell. “Polar bears will occasionally kill any reindeer. But since polar bears are technically a marine mammal, they just usually actually don’t have much spatial overlap.” While there are differences in individual reindeer, many are pretty calm when approached by humans and are even seen roaming towns in Svalbard. While other members of the deer family are notoriously skittish, Dwinnell says that some  Svalbard reindeer will let her and her team get within 100 feet or less. Svalbard reindeer weigh about 6.6 pounds at birth and 22 pounds once they are weaned. CREDIT: Photo by Maggie Coblentz. They are master adapters Like other reindeer and caribou, they have adaptations for their ever-shifting world. They technically live in what’s considered a high arctic desert where there is not a lot of deep snow, but it is still very cold. Summer temperatures typically only reach the mid-40s Fahrenheit. “Their hooves can essentially be zero degrees Celsius, while their core body temperature stays stable,” explains Dwinnell. The cell structure in their eyes also changes from the winter to the summer to allow them to see more of the low lights in the winter and deal with almost 24 hours of sunlight during the summer months.  Their legs are also shorter and closer to their body to prevent losing heat. As far as their added weight, it’s all about reproduction.  “With all reindeer and caribou, that’s [the fat] the currency they use for survival and reproduction,” says Dwinnell. “These animals manage to somehow be particularly fat, despite the low growing vegetation here. Basically they rely on those fat reserves to handle the long winters here.” Their hair–twice as long as any other reindeer–also serves the same purpose. [ Related: Reindeer can see UV light—and we may know why. ] A special sense–for plants Most reindeer and caribou eat lichen–a hybrid of algae or cyanobacteria that grows on bark, wood, mosses, rock, soil, peat, glass, and even human-made materials such as cloth, metal, and plastic.  “There isn’t a whole lot of lichen available to them here,” says Dwinnell. “So Svalbard reindeer are a bit unique in their diet, in that they largely eat grasses.” Since they are quite dynamic in their responses to their home, they are also quick to adapt to changes to their food sources. For example, during periods of rain-upon-snow events where the vegetation is frozen under ice, they will change where they go to find food. They will also watch for more seasonal changes  “As autumn comes and plants start to die, all of their nutrients go into the roots of the plants,” explains Dwinnell. “We found that Svalbard reindeer actually go to these places where they can dig up into the soil, then they eat the roots of the plants during these years where it’s warmer.” Male Svalbard reindeer develop large antlers from April to July and lose their antlers in early winter. Females will develop their antlers beginning in June and these bones usually stay the entire year. CREDIT: Photo by Maggie Coblentz. When the tundra froze in mid-September and there was still a lot of green vegetation above ground, Dwinnell and her team did not observe any reindeer digging to find nutrients because the nutrients were frozen into the above ground vegetation. “They have some kind of ability to gather information of where the nutritious food is, even if it’s not where the nutritious food is on the landscape, but where the nutrition within an individual plant lies,” says Dwinnell. “They’re able to target that so they’re very specific in the way that they eat in response to the conditions that they’re dealing with. ‘Flamboyant’ attempts at kicking While they are pretty docile, some of them will react when approached by a human or something it perceives as a threat.  “Svalbard reindeer do this little kick where they kind of, go up and try to kick but oftentimes they’re so fat that they barely leave the ground,” says Dwinnell. “Unfortunately for a lot of the readers that want to think that reindeer fly, they sort of disprove their ability to fly with their front legs. It’s just this very flamboyant and quite hilarious.” [ Related: Polar bears adapted to the Arctic just 70,000 years ago. ] They’re weathering climate change–for now A great deal of Dwinnell’s research focuses on how they adapt to changes in the vegetation and landscape of Svalbard. Their responses appear to be very quick and effective, but there are still some concerns.  “Not all populations have the same access to good food, and so there are some that don’t do quite as well,” says Dwinnell. One of their primary concerns is their lack of heat tolerance amidst increasingly broken high temperature records. While longer periods of warmer weather may lead to increases in vegetation, stress from heat may use energy that takes away from the gains that they get from more vegetation. Still, despite these pressures, Dwinnell considers them a hopeful species. “I think they speak to the nuances of how climate change can affect animals,” says Dwinnell. “At least for now, they seem to be doing mostly okay.” The post Shorter, fatter, and hairier: 5 fun facts about the world’s smallest reindeer appeared first on Popular Science.