Continuing from this discussion: Why might it be desirable to engineer aquatic humans? In a society in which humans have been bio-engineered for a partially marine lifestyle (I mentioned otters and seals in the description, but penguins and freshwater turtles occupy a similar niche), what adaptations would be most helpful for this? Let's assume that these people are living on a planet which is Earthlike except for a higher sea-to-land ratio.
There are a number of evolutionary treats that would make humans more better suited for aquatic life. Some ideas are:
- Losing all hair (or most of it) and developing a smooth body would make them more aqua dynamic and that would make them faster for escaping predators and "hunting" under water.
- More hemoglobin in the blood, this is actually what allow seals to last longer under water that and myoglobin that is a very similar cell that lives on the muscles. Those two cells allow for a more efficient oxygen management in the body, so in turn there is no need for bigger lungs.
- Echolocation, like whales. Since you are engineering them you could make this possible. Visibility under water is very limited so echolocation would be a big advantage.
- Membranes in hands and or feet, this a classic i don't think i need to explain it.
Some more wild ideas are that you could even give them gills so they can breath and with them a sense of smell like the sharks. You could make possible for them to produce their own light or even electricity inside their bodies.