So as we all (may or may not) know, evolution takes place when something is necessary to survive or better live more convenient/comfortably (for lack of better terms). For instance we developed the ability to speak for better communication. Before being able to speak we had movements of hands and limbs and the emission of 'meaningless' sounds - over a period of time we evolved the ability to add meaning to these sounds, and these sounds became words. (We also developed something called a 'hyoid bone' - this is a horseshoe shaped bone in our mouth under our tongue that is not attached to any other bones which allows us to better articulate words when speaking them.)
We developed hair for obvious reasons, to keep warm during colder temperatures. What happens to animals during the summer and/or warmer months of the season? We shed our hair. (Yes, humans are animals too by definition and technicality!) Why? Well, obviously to keep cooler!
We have developed a plethora of abilities and natural defenses to protect us and react to the environment around us over the many many years we have been on this planet, and we see to this day that we are evolving and still developing other abilities/defenses to help us better survive and live in the environment that surrounds us.
This is just how life works, not just humans.
All of this being said, I would like to ask the question, do you think we will ever develop the need to see in the dark - ergo leading to the development of 'night-vision'? Or do you think as long as we have the sun and the 12 hours of light every day we will never require the ability to see in the dark, and just retain our current abilities?