Let’s keep things simple two rules.
- No giving sentience, This is a no brainer issue.
- Let’s keep it to beings under the Animilia kingdom. “mutated virus/bacteria” is a common trope.
To start:
Let’s modify ants to have lungs.
Most insects are constrained by the amount of oxygen they can acquire through their exoskeleton.
Imagine how big they can get if they didn’t have that constraint?
Octopodes no longer die when they give birth, meaning they can teach their young and form societies.
Ok, take this with a grain of salt because I read about it ages ago in a dubious pop-sci book and my memory is shaky. One time, they tried to gene edit yeast to be able to survive much higher alcohol concentrations. There’s lots of good reasons to want to do this… Beer/wine is just about the strongest beverage you can make without distillation of some kind because the yeast dies. Making way higher ethanol yields just from fermentation makes biofuel way more viable. Stuff like that.
EXCEPT… It nearly escaped, and was able to survive on it’s own. Yeast is very ubiquitous in nature, so a wild yeast that can tolerate massive ethanol concentrations could conceivably have altered life on earth as we know it.
A cursory internet search isn’t turning up anything about this, but I’m pretty sure I read it in the book Everything Is Going to Kill Everybody, if anyone wants to look harder than I did.
A breed of 100+ pound Chihuahua with the same temperament as the original.
Amaranth that can grow on sand and be watered with seawater
Give any animal the ability to photosynthesize. Now animals are of course complex creatures that need a variety of nutrients to function properly, and the number of chemicals we’ve seen be able to be photosynthesized is low, but imagine only needing to nude sunbathe for like a half hour to get enough sugars to fulfill your caloric intake, including the less efficient carb->protein/carb->fat conversion and pop a pill for some vitamins. Imagine if all animals had that as a baseline and just needed to hunt/forage for nutrients and vitamins to support auxillary functions.
Overpopulation would be nearly impossible despite massive population booms, with the only real limitation being physical space and the social dynamics of any given species or interspecies interactions.
The reason you don’t really see animals that can photosynthesize (other than microbes) is because you don’t actually get that much energy per unit of area. Think about how much area a cow has to graze vs the surface area of the cow itself. And much of the cow’s surface isn’t even facing the sun.
