How to make humans… but on an alien planet

Based on a comment from my post a few weeks ago! The idea I’m exploring is how to change humans, slightly, but enough to live on a different planet (starting with Earth-like conditions). I’ll just look at places in our solar system, but in case of some like Venus or Jupiter these would be more like dramatic changes. If you would like me to make humans to live in other planetary systems, let me know… but I don’t know enough about other systems enough to do so. For those unaware, my posts are just speculations, and it's definitely not realistic, but it's a fun way to think about other ways we could live in the future. Human engineering, of course, requires a massive amount of thought, but the basic idea of how we can change to live on Earth… but what if that planet wasn’t Earth?<br><br>I’ll start with one of the closer planets/moons, and change it to the most similar to Earth humans… so the humans will change the least. Let’s start with Europa.<br><br># Europa<br><br>If humans evolved on Europa, the biggest problem we would need to overcome is staying warm - due to the lack of sunlight and lack of tectonic plates, it’s pretty cold there. The humans would need to overcome the temperature one way or another:<br><br>&#x200B;<br><br>They developed scales - cold blooded both helps regulate heat and conserves energy, but we would likely have less calories to start with. We would evolve thicker skin to keep the warmth because it is so cold out. They developed… something like what axolotls have on their cheeks (feathery features) that have blood flow through to catch what little heat happens to be available. The skin might be a bit more moist and reflective to take in as much heat as possible.<br><br>Since they have a hard time taking in heat, let’s assume they… lost their teeth. They didn’t need them, they ate whatever scraps of algae they could take from the surface or their mouths developed a sort of probiotic filter that digested whatever food came through? They also probably lost their hair and their skin developed some sort of gills because it’s an aquatic system… but they probably didn’t have the probiotic filter because it would be hard to get all the nutrients needed. We definitely lost the hair. The hair is long gone on these humans.<br><br>Similarly to the idea of axolotls, these humans never lost their gills, so they likely never developed lungs… but they would definitely need some other way of taking in oxygen because gills don’t work out of water. Let’s assume that the gills are just very… finned… and take in oxygen more efficiently than typical fish gills. Their noses are more vestigial… except… they have some sort of proboscis that is sensitive to chemicals and can detect… something… what chemicals do axolotls have in the water? Does it seem likely that the features of axolotls would be useless in this environment? Plus their eyes are probably slightly more sensitive to light… like owls. Not fully nocturnal but definitely more attuned to because it’s just so dark in that environment.<br><br>They also probably developed… webbed feet and hands of some sort, but I’m not sure if it would be enough advantage to fully form. The water is cold, so they probably wouldn’t swim much and would likely just scuttle around.<br><br>Would humans on Europa have anything like technology? There is no… wood… or plant life on their planet… so while they might be able to mine whatever minerals are on Europa… they probably wouldn’t have anything like fire to make metal… so technology is probably… hard. But maybe they have some sort of bioluminescence? Or maybe if enough ice shelves fall down from the top layer of ice, they could have wood to make wooden… boats… or something… but I don’t see it being enough to make their lives technologically advanced. They live in the dark. It’s hard to describe too much about it, but it’s definitely a distinctive society that relies heavily on echolocation and touch… like bats and dolphins. They probably developed bioluminescent vision which might reduce the brightness but increase the range of light, but it’s definitely still a very dark world.<br><br>&#x200B;<br><br>Kuiper Belt Human 1st Appearance: 78 days<br><br>Kuiper Belt Human 2nd Appearance: never, humans evolved in the Kuiper Belt