Hello, human. Well, I’m guessing you’re a human. Most organisms browsing the internet are (I apologize to any super-intelligent cats out there reading this right now. Forgive me.). As humans, we’re pretty lucky. We have eyes that can see a spectrum of colors. We have brains that can invent spaceships. We have arms that can throw balls really fast. We have taste buds that can enjoy french fries (MMMM FRENCH FRIES). For all of these traits, we have nature to thank. Thanks, nature. Over millions of years, evolution has provided us humans with all of these amazing abilities we get to enjoy. These, nowadays helpful abilities we possess, millions of years ago were just tiny DNA mutations in our ancestors. But over the 4.6 billion years, since the beginning of planet Earth, nature has had some mysterious survival traits up her sleeve. And not all animals have been quite as evolutionarily lucky as us. From the perspective of humans, some animals have traits that seem way less cool than what we got. Traits that may even think seem unkind, unnecessary, or unfortunate. Before we jump into the animals, know this: nature and evolution are never actually unkind to any species. Nature can’t be unkind. Nature just is. All traits that these animals possess provide some sort of biological advantage in the animals natural environment. So however strange it seems, they actually do work out for the animal in the long run. So take a moment before reading on and be thankful that you’re a human!
Horses are filled with biological issues. And maybe it’s because humans have artificially created the modern horse through selective breeding. But even still, it’s tough to know where to start when we’re talking evolutionary challenges. First of all, horses can’t breathe through their mouths. Almost every other mammal has the ability to breath orally if their nose becomes clogged. It’s an alternate survival method to retrieve oxygen. Another trait that poses a challenge is that horses can’t throw up. And I don’t mean that they just don’t like throwing up (honestly, who does?). It’s physically impossible for horses to throw up. For most vertebrates, the ability to immediately rid your stomach of toxins is an essential evolutionary advantage. If you’re not able to vomit, you have no way quick way to remove toxins from your body. Horses stomach muscles are built in a way that prevents vomiting. The valve from their stomach to esophagus so strong that it cannot physically open to remove contents from the stomach. Many horses that ingest toxins require intense and immediate surgery or they’ll end up passing away. Ok, but there has to be some evolutionary benefit to this lacking ability. So why can’t horses throw up? Scientists still aren’t too sure. The leading theory states that horse stomachs are built this way to prevent vomiting while trotting at high speeds. The trotting motion may induce vomiting which would cause predators to easily prey on horses that had to slow down to throw up.
2. Giant Isopods
Imagine living your entire life in a completely dark room and only eating decaying animals that drop from your ceiling. If that sounds like a party to you, try dressing up as a Giant Isopod for Halloween next year. Or hoping you’re reincarnated as one in your next life. These seafloor dwellers can live up to 8000 feet under the ocean where there is absolutely zero sunlight. In these dark, ice cold waters, they survive by feasting on the dead animals and fish that float to the bottom of the ocean. What’s the evolutionary benefit? Giant Isopods actually have a pretty good setup, relatively speaking. They have limited competition this far under the ocean and it’s pretty much guaranteed that fish and animals are going to keep dying and falling to the ocean floor.
3. Adult Luna Moths
You’ve probably met a Luna Moth (specifically of the Saturniidae family) or two in your day. But don’t get too attached. These little buggers might be hard to keep as a pet. These large beautiful moths live most of their lives as caterpillars. Then once they emerge into a moth, they have no mouths and no internal digestive track. Not a great recipe for longevity. Adult Luna Moths fill up on food when they’re in the caterpillar stage, just so they can reproduce as soon as they become a moth. Then they make their grand emergence and die a few days later. Major downside of not having a mouth. Why, nature? Why? From nature’s point of view, it’s actually pretty efficient. Why waste all that time and energy creating a mouth and digestive tract when you’re already on your way out? Better find a mate and pass on those genes quickly, though!
We all know how slow sloths can be. Even in the animated movie, Zootopia, DMV workers are portrayed as sloths moving paperwork at an insanely slow pace. These slow tree dwellers had to make the list. How could an animal this slow still be surviving on our planet? Surprisingly, sloths have been on earth for over 60 million years, so they must be doing something right. Their slowness is actually an incredibly efficient survival tactic. They conserve energy better than almost any animal on the planet, so they don’t have to eat much food at all. Since they move so slow, they are often undetectable to predators like big cats or large birds. Sloths slow pace allows them to slip right by the visual radar of these animals. Along with their slowness, sloths also have a strange pooping ritual. Instead of pooping from the trees (which seems pretty efficient), sloths spend tons of time and energy going all the way down to the forest floor to relieve themselves. It exhausts almost all of their daily energy and makes them more susceptible to predators. Why do they do this? Scientists have theorized that this daily pooping ritual may be a social activity among sloths. Since they descend the tree together as a group, it may be a time for sloths to catch up with each other and hear how life is going. Another theory is that it may be a survival tactic to lessen the noise as opposed to releasing their droppings from the treetops.
At first glance, it might seem cool to be a bee. You can fly. Most plants owe you big time for spreading their seeds. All that importance could go to your little bee head. One challenge that bees face is that they produce a deliciously tasty substance. This tasty substance, also known as honey, also known as bee vomit, is one of the sweetest naturally occurring foods on earth. And it just so happens that large apex predators like bears, enjoy slurping down an entire hive of honey (bees included) whenever they have the chance. When this happens, bees only defense to save their hives is to sting the bear. A defense which is only mildly irritating to the bear, but is deathly to the bee as the bee’s internal organs as ripped out of its body and is left to die. Rough. Thanks, nature.
6. Sea Louses
You might remember being checked for lice in middle school. But did you know that some lice exist in the sea? Nature has given the female sea louse a rough go. They deserve an award for Best Mothers of The Last Billion Years. The tiny little crustaceans have a rough going when it comes to reproduction. First of all, the male sea louse drags up to 25 females at a time into his special dungeon. After being impregnated, the weight of the babies is so heavy for the mother that she has no other option but to stay in the dungeon until she has her babies. And we’re talking live louse babies, no eggs that hatch later on. But here’s the roughest part for Mama Louse: the babies are born by chewing their mother from the inside out. UGH. Sounds like the start of a horror Stephen King novel.
The moral of the story? Be glad you’re human. That’s all.