Why do most deep sea creatures look like they’re hell-spawns?

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Why do most deep sea creatures look like they’re hell-spawns?

In: Biology

15 Answers

Anonymous 0 Comments

At the bottom of the sea it’s both immense in both pressure and darkness and so their bodies have adapted to both of these by getting all hellspawnish and losing things like eyes and whatnot. For an even simpler explanation shits heavy down there and they have no one to impress and so they all just wear whatever works.

Anonymous 0 Comments

There are a lot of good answers here already but something I want to add (as someone who works in this field) is that I think the ‘deep sea creatures are scary and hellish’ narrative is a bit of cherry picking. [There](https://www.wired.com/2013/09/absurd-creature-of-the-week-bobbit-worm/) [are](https://www.bbc.com/future/article/20190808-why-do-sharks-attack-humans) [plenty](https://www.independent.co.uk/news/science/new-species-terrifying-looking-skeleton-shrimp-discovered-8962913.html) of scary looking animals that live in shallow regions and [there](https://www.youtube.com/watch?v=9D0eyl7-XQA) [are](https://www.youtube.com/watch?v=pxuBwfNp2wk) [plenty](https://www.nature.com/articles/d41586-018-06660-2) of cute or beautiful animals that live in deep waters.

I have a theory that everyone has at least a little bit of thalassophobia and sharing the scariest deep sea animals around helps confirm that bias.

Anonymous 0 Comments

Because they’re really far on the evolutionary tree. Seriously people like cats and dogs as pets, rarely dinosaurs (birds) or fish but we are closer to fish then fish are to octopus.

And it’s the same with insects, crabs and jelly fish.

I assure you the insectoid aliens from District 9 didn’t find lobsters that creepy.

Then there’s also the evolutionary effects on our monkey brains, so like how we’re all inexplicably afraid of snakes and spiders even at a young age, even by lookalikes.

And lastly life experience, if you don’t see that many creepy crawlers then you’re more impacted by the rare encounters, I look at the serpent handlers and aligator wrestlers in awe.

Anonymous 0 Comments

Because the physics they’re working with is different. Theres a lot of videos circulating around youtube of marine biologists who can’t readily identify even well known species on camera simply because of the way they move or contort themselves, like how gulper eels can inflate themselves and squirm around because living deep under water makes that both possible and a thing there are advantages to doing. Same for how large whales can orient themselves weirdly when they sleep or prepare for mating and sometimes their reproductive organs get taken for weird sea monsters by some sailors. Or how some fish can have asymmetrically positioned eyes or eyes that see through translucent skin.

All of these features are bizarre to us but make sense to those creatures because they play by laws of physics where moving in three dimensions is the norm, gravity matters less than the behavior of the water they’re in for movement, and the amount of oxygen and nutrients they can access varies wildly by much more than on land.

This is also why humans generally need lots of equipment that looks weird and a lot if specialized training to get very deep. The pressure of the ocean will destroy the human body a million different ways because the human body isn’t designed for that environment and even with equipment safety procedures need to be followed going down and coming up. But these weird creatures can spend most of their lives there because their bodies are adapted to handle it.

Anonymous 0 Comments

They evolved to deal with conditions that are completely alien to us. As a result, they share very few traits that are recognisable to us.

The animals that we find the most appealing, are usually the ones most similar to what we find cute. Usually, other mammals that are warm, soft, have eyes and expressions that we can imagine we see emotions in.

Deep-sea fish are not that. For instance, there’s extremely little light down there. Not enough to really see by as we do. Deep-sea fish tend to have enormous bulbous eyes. Those eyes don’t really let them see things but those huge eyes might just be enough to see other fish or animals as they pass overhead and block what extremely little light filters down from the surface.

Noticing that might make the difference between going hungry and catching prey, or spotting a predator and avoiding becoming prey yourself.

The lack of light also means the colour works very differently down there. There’s not much point in being colourful if nobody can see you. So many deep-sea fish just have that pallid corpselike absence of colour.

Others are transparent to avoid casting a shadow against the faint glow of light from above. Some fish are bright red as a form of camouflage. Low energy frequencies of light are filtered out first as you descend underwater. That’s why things quickly start to look blue-greenish.

Red is the lowest energy frequency of light. So red part of the light spectrum is the most absent in the deep. Without red light to reflect, the colour red is basically invisible. Most deep-sea fish have completely lost the ability to see red.

Speaking of prey. Without sunlight, nothing grows down there. Small animals can survive on marine snow. Basically tiny flakes of organic detritus that constantly come down from above. Slightly larger animals can eat the filter feeders that survive on marine snow. But larger animals like deep-sea fish only have one food source available. Each other.

The deep-sea is essentially a freezing cold, pitch-black desert. Everything is scarce down there, including opportunities to eat. So most deep-sea fish have maws full of long needle-like teeth. Essentially they can’t afford to let prey escape. So when they manage to grab prey, those maws full of needles make sure that prey can’t slip their grasp.

Deep-sea fish have many other adaptations to deal with the scarcity of food down there. Many fish have enormous mouths so they don’t have to pass up on larger prey. Some have incredibly stretchy mouths and stomachs to the point where they can swallow prey that is bigger than they are.

Others develop some truly alien adaptations like little bioluminescent lights to attract prey. Remember how red is essentially invisible down there because there’s no red light? There’s one predator that has its own bioluminescent red spotlight that allows it to easily find red fish in the dark.

The weirdness just keeps going. Energy preservation is very important down there so most deep-sea fish are ambush predators that don’t swim around much. As such, they don’t have the neat hydrodynamic torpedo shapes we usually associate with fish. Many are just sort of shapeless and blobby to help them deal with the pressure.

And they developed many other strange adaptations. When a male angler fish finds a female, he never lets her go. It’s very hard to find a mate in the dark emptiness after all. Instead, he bites down on her body and slowly fuses with her to become part of her. The male is nourished by connecting to her bloodstream and slowly wastes away until the male is little more than a pair of gonads attached to the female to provide sperm for her eggs.

Simply put, the deep-sea is a completely alien environment that places very unusual demands on its denizens. They look frightening and alien to us because nothing about them makes sense to us in the context we’re used to. Their proportions are bizarre, their eyes are disturbing, their teeth look like a nightmare.

But for them, those are just the tools they need to survive the world they live in.

Anonymous 0 Comments

To add to what others have said: In some cases like the [Blobfish](https://www.smithsonianmag.com/smart-news/in-defense-of-the-blobfish-why-the-worlds-ugliest-animal-isnt-as-ugly-as-you-think-it-is-6676336/), they actually have a somewhat normal appearance in their extreme deep sea environment under 1800psi of water pressure. When they’re brought to the surface at 15psi of atmospheric pressure they turn into a gross blob. You wouldn’t look so hot exposed to the vacuum of space either, and that’s 120x less of a change in pressure than poor ol’ blobby.

Anonymous 0 Comments

It really doesn’t help that a lot of the pictures you see are after they’ve been rapidly decompressed. If you see one at the surface, it’s organs have likely exploded and it’s features distorted.

Anonymous 0 Comments

Alongside what /u/Arclet__ said, the other reason why they’re so hideous is because they’re literally optimized to butcher and kill each other.

In the bottom of the ocean there’s no plants, the closest herbivore analogues being scavengers. It’s literally dog-eat-dog in a hellish environment where energy and food is scarce, so these creatures evolve to 1) spend as little energy as possible by drifting for the most part in the infinite dark, 2) have a mouth as large as possible, horrific teeth that WILL sink deep into prey to prevent escape, and jaws that unhinge and swallow in split seconds. These make the difference between life and death in the abyss.

Anonymous 0 Comments

Looks aren’t going to be selected for when things have a hard time seeing in that level of darkness.

Anonymous 0 Comments

There is no light in the depths so the guys don’t see they are mating with ugly girls. Evolution does the rest…

Joking aside, there is no need for any creature to look pretty to us. In this particular case, nobody bothers to print or talk about mundane-looking animals. They are boring. Whatever you have seen as a person who doesn’t really have a clue about marine biology is something that passed through a very high threshold of being interesting enough for mass media. This means extremes, like monster-like ugliness.

This is called selection bias.