How would the human eye need to change in order to see in low light without any changes to physical appearance?

In my world there are humans who have undergone a mutation from being exposed to a certain kind of magic. They have not realized they have been mutated until they start noticing that they have the ability to see well in the dark (low light, not total darkness). Outwardly, they look the same as they did before the mutation, which is why no one noticed they had been mutated. They can also see just fine in the daylight as before.

I'd like to avoid a 'they can see in the dark because magic!' situation, and put more focus on the effects of mutation and how their eyes have changed biologically.

So, biologically speaking, how would the human eye need to change in order to see in near darkness without any major changes to physical appearance (like larger than normal pupil dilation)? Also, could this happen without jeopardizing the ability to see in daylight?

posted about 7 years ago

anwen‭

1 reputation 2 0 0 0