The North Pole lying in the Arctic region is one of the harshest environments in the world. Amy Hall introduces 3 animals with unique adaptations permitting their survival.
The North Pole isn’t just a fictional place with Santa, reindeers, and snowmen. It is a real place on Earth that sits right in the centre of the Arctic Ocean. This means it is part of the Arctic region, alongside parts of Canada, Northern Finland, Iceland, Northern Norway, Russia, Northern Sweden and parts of the United States. All of this land inside the Arctic Circle, makes for an incredibly unique place on Earth.
Researchers at the North Pole. Image Credit: Daniel Fatnes on Unsplash.
Sitting in the middle of the Arctic Ocean, the North Pole is considered the most northern point on Earth. During winter in the Arctic there is absolutely no sunlight, and in the summer there is no darkness. It is also classed as a desert, which is bizarre as there are recorded temperatures here as cold as -70C. This means wildlife has to be very well adapted to live in the Arctic region.
The Arctic circle. Image credits: CIA World Fact Book on Wikimedia Commons.
Arctic reindeer (Rangifer tarandus)
Of course, since it’s December, we’ve got to talk about Arctic reindeer, or as they’re known in America, caribou. You either see these flying over your house on Christmas eve, or the rest of the year they spend their time in the Arctic Tundra - open plains of the Arctic. As mentioned before, the Arctic is incredibly dry and cold, this means the air isn’t pleasant to breathe. Therefore, reindeers have nasoturbinal bones in their noses. These bones support thin tissue filled with warm blood, so that when air passes through their nose, the warm tissue heats the air up before it travels into their lungs.
An incredible new discovery for the reindeer is that they have UV vision. They haven’t been blessed with being at the top of the food chain and compared to most of their predators they haven’t got any camouflage against the white snow. But seeing UV light means that their predators will show up as dark silhouettes due to absorbing UV, whilst the snow reflects it. This gives reindeers a bit of a head start to get away from being eaten.
Reindeer/ Caribou. Image credit: Deigo Delso on Wikimedia Commons.
Narwhals (Monodon monoceros)
My first experience of narwhals was watching my favourite christmas movie of all time, Elf. Known as unicorns of the sea, these animals are already unique and almost mythical. Interestingly, the obvious tusk that makes them so unique, is only usually present in males and around 15% of females and technically is just an elongated canine tooth. For a long time, scientists didn’t really know what the point of it was. You’d assume it was for fighting, as it could definitely cause some serious damage if narwhals wanted it to. However, they’ve now discovered it’s predominantly there for sexual selection. Essentially the bigger the tooth, the more attractive the narwhal.
Being part of the cetacean family (dolphins, whales, etc), some adaptations are to help them dive deeply and for long periods of time as they are warm blooded, and have to surface to breathe air through their blowhole. They have also adapted to be able to slow down their heart rate. When they’re diving and oxygen is limited, the heart slows down, sending oxygen only to the vital organs such as the brain and heart so that it can be conserved. The official term for this is bradycardia.
As well as this, narwhals have an abnormal amount of myoglobin. Similar to haemoglobin, they’re both large molecules that carry oxygen around the blood. The more myoglobin they have, the more oxygen they have. These, along with many other adaptations, mean that narwhals can dive up to 4,900ft for up to 25 minutes.
A pod of narwhals. Image credit: Dr. Kristin Laidre, Wikimedia Commons.
Arctic tern (Sterna paradisaea)
The Arctic tern is also definitely worth mentioning. It's occasionally spotted in the UK while passing from one pole to the other to enjoy a never ending summer. This in itself is an adaptation, in my previous article ‘wings of change’ I spoke about how most birds follow where the food is. Spending time in the Arctic during the Arctic summer and migrating to the Southern pole when the Antarctic is coming into summer, means that the Arctic tern will be in both places when their food is at the highest abundance.
Arctic terns must eat a large amount of high energy food, usually very oily fish, which they then burn to produce heat. This is an adaptation of many birds that live in colder climates and explains why the Arctic tern always needs a constant supply of food.
As you can imagine, flying from one side of the Earth to the other is no easy feat. That’s why, they’ve got versatile tail feathers that can change shape to suit the activity, hollow bones to make them lighter and tiny legs to make them aerodynamic (although not quite as useful when they land).
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