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Some fish will never win any beauty pageants, but they still deserve our admiration, respect, and love, especially since their “ugly” traits are actually incredible examples of evolutionary innovation.

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When we think about residents of our oceans, lakes, and rivers, we often focus on beautiful ones, like colorful angelfish or the invasive but stunning lionfish, but what about the fish that are a bit, well, homely?  Things like blobfish or wolf eels certainly aren't winning any beauty pageants, but they still deserve our admiration, respect, and love, especially since their "ugly" traits are actually incredible examples of evolutionary innovation.

Their strange shapes or creepy appendages help them win over mates, find food, and generally live their best lives in unique and sometimes surprising ways.  Besides, they're not trying to impress us, so let's give seven of these not-so-stunning fish their moment in the underwater spotlight.

1) Blobfish

When you think of an ugly fish, the blobfish is probably the first one that comes to mind.  I mean, it was voted the ugliest animal in 2013 and it's just so pink and fleshy.  Basically, the embodiment of how people feel when they hear the word 'moist', but that description is pretty unfair.  These deep sea fish from the Southwest Pacific live in a world where there is a lot more pressure and that squeezes their gooey tissues into a much more respectable fish-shape.  In fact, the specimen we're all familiar with is a decade-old fish that was preserved in alcohol and any of us would look a bit squishier after that.

Blobfish tissues are gooier than average, though, and for good reason.  It helps them survive the pressure of living in the deep.  Bones and other rigid support structures are too prone to cracking under such intense pressure, so the blobfish has gone soft everywhere.  Plus, the goo likely helps them hover near the bottom.  See, many fish have a gas-filled swim bladder that they can use to regulate their bouyancy.  It's basically the same idea as those inflatable vests scuba divers wear.  

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Add more air into the bladder and the fish rises.  Release some air and they sink, but air pockets are too hard to inflate in the deep.  The blobfish's jelly-like tissues, on the other hand, can withstand the squeeze and they're probably a little less dense than sea water, which would allow them to float just above the sea floor while they wait for a tasty morsel to come by.  Plus, they're cheaper to make than regular muscles, which matters if you live in the cold depths where food is scarce, and all that jelly may even help them swim more efficiently.  As studies suggest, it could reduce drag along the fish's tail.

2: Stargazers
Oh, boy, where do I begin?  Are they ugly because of their upturned eyes or their comically large goofy mouths?  Well, both are awesome adaptations to their hunting strategy of, well, not actively hunting.  These sneaky fish can be found along the Atlantic coast of the US, but they're not easy to spot because they use their pectoral fins like shovels to bury themselves in the sea floor.  Then, they sit and wait for an unlucky morsel to swim overhead. 

Since they end up largely underground, it's helpful that their eyes and mouths are more on top of their bodies and the large size of their mouths is also perfect for insta-gulping.  When they quickly open it, it creates a vaccuum that sucks in any small critter swimming by, but it's not just their appearance that's unusual. 

According to a 2015 study, members of the stargazer family, uranoscopidae, have a lot more bile in their bodies than expected.  This increased bile may help them absorb calcium in their gut so they can build unusually strong bones, specifically, their craniums.  We don't know why they need such tough skulls, though.  It'd be tempting to think that it's to withstand the pressure of a misplaced heel.  It's not like you'd see them before you stepped, but of course, there aren't a lot of heavy things walking around on the ocean floor and even if there were, these amazing fish have another way of dealing with assaults from above. 

They have an electric organ in their head that lets them shock things, so they can zap any potential predators that get too close for comfort or a clumsy foot.

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Hey buddy, you got a little something--oh wait, no, that's your nose, isn't it?  Yes, bristlenose catfish have shnozzes only a mother could love, or another catfish.  Turns out those nasal projections aren't feelers, and they are much more prominent in males and that's probably because they're a sexual signal.  The bristlier, the better, according to females. 

Biologists aren't 100% sure why females are so enamored with the bristles, but they have a couple of ideas.  It may be because they kind of look like the catfish's babies, which is a good thing.  See, males of these Amazonian catfish species create and protect nests for their future young.  Females decide who to spawn with based on these nests, and multiple females may lay their eggs in the same one.  In fact, females seem to prefer males whose nests already contain eggs, so it's possible males with more bristles look like they're successful daddies, even when they're not or the tentacles may actually help a male be a better dad.  Some research suggests they produce a gooey substance which could be used to nurture their young.  Either way, a nice, bristley mom makes a male catfish irresistible to potential mates, so it doesn't really matter to him that some gangly apes think he'd look better with a shave.

4. Bumphead Parrotfish
The giant bumphead parrotfish looks like it recently swam headfirst into a wall, and that's not actually far off.  I mean, the bumps aren't bruises.  They're hard and bony, but ichtheologists do think they're used for headbutting, specifically by large males in dominance displays that secure them mates and territory.  Researchers studying these fish in the Indo-Pacific waters they're native to have observed male bumpheads crashing into each other at great speeds.  This makes a distinctive loud thwack.  Imagine two big rams but underwater, and after impact, the fish circle each other, attempting to bite each others' backs.  Then, they swim a short distance apart and face off for the next round.  This explains why the bumps are so much bigger in males, though females do have them, too.  Of course, that head bump isn't the fish's only unattractive trait.

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Its mouth is also a bit of a nightmare, because the teeth are fused together into a big solid beak.  They use those to basically eat rocks.  Like all parrotfish, bumpheads eat by scraping off chunks of rock and coral.  Any living bits from coral tissue to algae are the real food.  Then, they grind up the inedible stuff and poop it out as sand.  Lots of sand, potentially hundreds of pounds of sand each year.  Just think about that the next time you're walking on a beautiful white sand beach, and even though they can eat corals, they're actually really good for reefs.

That's because their scrapes keep algae in track and open up real estate for coral growth.  Plus, the tend to consume fast-growing species, which gives slow-growing species more room to expand.  

5. Redlipped Batfish
The redlipped batfish, which is native to the Galapagos, looks like it's aiming to be the next big beauty vlogger or maybe sewer dwelling clown, and in addition to that namesake red mouth, it's got a whole suite of less than adorable traits, like those appendages that look like crouching bat wings and that big horn-like number protruding from its head.  There is a lot to unpack here, so first, let's talk about those lips. 

Scientists actually aren't sure why this fish has a pout bolder than Miranda Sings, though it's possible it plays a part in attracting a mate, as males are redder than females.  As for those weird appendages, they let these fish stroll along the sea floor and they could help us understand how our ancestors crawled onto land.  It's not entirely clear why fish would wanna walk instead of swim, mind you, but a number of bottom dwellers do it and redlipped batfish can swim in short bursts, but most of the time, they use their pseudo-legs to scuttle around, kind of like a crab, or grab on to something and stay perfectly still.  That's helpful when you're trying to sneak up on a snack, which brings us to the last but not least weird trait of this fish: that thing on its head.

It's called an illicium, and it seems to be important for feeding.

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Studies on related species suggest it's useful for digging around in the sand for buried meals, though in general, it's thought to act as a lure.  It's not clear if it looks yummy, though.  Researchers think it might draw in curious fish by vibrating just the right way, and it might even secrete a chemical to tempt its prey closer.  

So while you might not find this fish attractive, what it eats probably does.  

6. Wolf Eels

Wolf eels made this list in large part thanks to their pointy canine-like chompers.  Those are where the wolf moniker comes from, but not all of their teeth are sharp like that.  In the back, they just have these domed nubs.  Having such different teeth allows them to nab pretty much whatever they want.  The pointy canines in the front can pierce and therefore grip onto all sorts of fleshy meals that might otherwise slip out of their mouths.  Meanwhile, the fish retain the ability to crush hard things, because those nubs in the back are well-shaped for withstanding pressure without cracking, so they can snag fish and squid and the like and also consume things like crabs, sea urchins, and sand dollars. 

Also, they're not actually eels, just long, skinny fish.  That length comes in handy in a couple of ways.  After spawning, they can wrap their long bodies around their eggs to protect them, which is kind of sweet, and when they're not guarding offspring, that eel-ish shape allows them to back into tight spaces while leaving their heads out to catch prey.  You might have noticed those heads are also a bit oddly shaped.  One of the big reasons for that is that they house really strong jaw muscles, muscles which ensure the fish can crush whatever they catch, and if that happens to be your finger or toe or something, well, you definitely regret talking smack about wolf eels.

7. Ocean Sunfish
Ah, the mola mola.  In the immortal words of those Boston fishers, is it hurt?  Is it a baby whale?  Is it something we ain't never seen before, kid?  Whatever it is, it looks like it might be missing the back part of its body, but it's not.  That bizarre shape lets it glide all around the world.  Also known as the ocean sunfish, the mola mola is one of the heaviest bony fishes.  

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We're talking about a whole ton when fully grown.  Still, people originally thought they just drifted along in the currents.  Then, satellite tracking revealed that these massive fish dive to depths 450 meters or more and swim all over the place, probably looking for food, and those weird fins that look like stubby wings, some scientists have pointed out that they're actually very efficient for cruising.   

When the fish moves its fins together, it creates lift-based thrust, much like a penguin does when it flaps its wings underwater, and like the first fish we talked about in this list, the ocean sunfish body also contains a lot of gelatinous tissue.  That helps it remain neutrally bouyant, without relying on a traditional swim bladder, which would be prone to over-inflating when the fish ascends from its deep dives.

So there you have it.  Seven not-so-pretty fish but whose ugly traits actually make them awesome, and the best part of all this is that these are just a taste of the wonderful weirdness living below the waves.