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The ability to breathe is something that we share with practically every creature on the planet.
We all need to harness and process oxygen and turn it into energy, but it’s not as simple as sucking in air, delivering it to the lungs and distributing it via the bloodstream. The animal kingdom has a baffling, remarkable and innovative number of ways to deal with respiration. Here are just a small number of the most amazing…
Glass frogs are astonishing for a whole host of reasons. Not only is their skin translucent, so some of their internal organs are visible (scientists have only recently deduced this is almost certainly for camouflage reasons), but they also have three completely separate respiratory surfaces. They obtain oxygen through their skin when they're submerged in water, they also have a breathing membrane on the lining of their mouth that can extract oxygen and they practice the traditional mouth/lung method as well. Meanwhile, the Bornean flat-headed frog has decided to do away with lungs altogether. It gets all its oxygen though the skin.
While I’m sure you’ve encountered the occasional person whose breath appears to have some connection to their hind quarters, birds actually use areas in their rumps to breathe. Our avian pals need to efficiently process oxygen to obtain enough energy to get them into the air. This is especially important for high-altitude birds, such as vultures, who soar over 30,000 feet where oxygen is scarce. To achieve this, birds have air sacs throughout their bodies, including their rear ends, which then transfer the air to their lungs. When the next breath is taken, this air is moved from the lungs to the air sacs and then the carbon dioxide released. This two-breath system means fresher air continually reaches the lungs and subsequently the bloodstream.
Did you know your left lung is slightly smaller than the right one? Why? It’s so there’s enough room to accommodate our heart. This is a trait we share with snakes who, in certain species, have given up on two lungs altogether and just have the one. The right lung is fully formed, while the left is just a small sac. As the snake evolved, their tubular bodies required longer, thinner organs. Where pairs of organs still remain, such as the kidneys, they are stacked on top of each other, rather than sitting side by side. So why bother having a vestigial left lung at all? In aquatic snakes, it is utilised as a buoyancy aid, but with land snakes… it’s all a bit of a mystery.
It comes as no surprise that the fastest living land animal, the cheetah, is purposefully built for speed. This includes the respiratory system, which is designed to get oxygen to the muscles as efficiently as possible, ensuring the big cat can reach its top speed of 60 miles an hour in only three seconds. Their respiration rate rockets from 60 to 150 breaths per minute, double that of humans, to fuel this massive expansion of energy. If the cheetah manages to catch its prey, it will take 30 minutes for the cat to catch its breath and consume the thing it’s caught.
Some animals seem to be asking for trouble when it comes to respiration. Take the humble sloth. For reasons best known to itself, it spends a massive amount of time hanging upside-down and doing… well, not very much really. As you may be aware, if you have spent any amount of time upside down yourself, it’s quite an uncomfortable position to find yourself in. Internally, your organs press up against your diaphragm and lungs causing breathing to be difficult. So how does the sloth manage it so successfully? Scientists have discovered that the creatures have developed the ability to ‘tape’ their internal organs to their skeleton using fibrous tissue to prevent them from moving when inverted. This saves the sloth much needed energy required for their non-energetic existence.
This wouldn’t be the animal kingdom without a curveball – and just when things appeared to be so nice and simple! As we’ve seen, there is a wide variety of ways for different animals to breathe (including butt use). You could even assume breathing is one thing all animals have in common – all except for one awkward customer. Scientists have discovered what they believe to be the first non-breathing creature. It is an ocean-dwelling, jellyfish-like parasitic blob called Henneguya salminicola, also known as ‘Milky Flesh’ and ‘Tapioca Disease’, which latch onto deep-sea dwelling fish. Unlike every other animal scientists have studied so far, the parasite has no respiratory component in its DNA. So how does it survive without taking oxygen onboard somehow? So far scientists are slightly flummoxed.
Featured image by © Westend61 | Getty