Okay I understand that the sun might be responsible for the evolution of human skin color, but how do you explain the change from brown to green to blue eyes? And how about black, brown and blonde hair? Not to mention frizzy to straight hair? How did this change? The sun has nothing to do with eye color, hair color, except that a lot of sun can make hair lighter but that actually contradicts the statement, and hair texture? Please give suggestions. Thank You.
I'm not an expert on this(I'm 16) and have asked myself the same question many times. I believe it largely depends on not only the environment but also sexual preference among the population. When a mutation first presents(for example, lighter eyes or hair), it is in only one or two people and is unique to their genetic code. If this is found to be more attractive and does not effect their survivability(as albinism would in a desert environment), the person with these traits has a high chance of passing this mutated gene to their offspring. If they too present this physical trait and it continues to be appealing to others, it will spread throughout the gene pool even if recessive. Overtime, each isolated group of people develops unique traits and genes. Though I don't believe this is the sole reason behind the differences in hair and eye colour, I believe it has had a big effect on them despite there being so many other variables. One must also look at how isolated a population was, if their culture tolerated marriage to foreigners, etc.
over a very long period of time people have evolved and now we have many different coloured skins, eyes, hair ect. this is because people from different countries are born with different colours. in one place of the world people have eveolved with dark skin and dark eyes, in places like africa, and in other countries people have eveolved with fair skin and light coloured eyes, in places like australia and stuff. this is widly due to the enviroment we live in. and also when people from different races/countries breed. its also down to genes. a mother and father could both have dark hair and brown eyes but have a baby with lighter hair and say blue eyes. because one or both of them were carrying the blue eyed genes. this is something that dosnt always happen though and can skip a generation or a few. which is why one family could have all brown eyed chilldren and then a blue eyed child as well.its basically all do to with our genes and the enviroment that weve evolved into.
It could be all due to the environment that the parents live in or the genes in the parents' bodies might play a part in determing which eye color or hair color the child has. Strong sunlight or no sunlight may also darken the skin or lighten the skin and even the hair, thus it is based on many environmental factors or genetic factors.
it's the same thing as skin. A thing called melanin decides the darknes of skin, hair and eyes. the more melanin you have, the darker you are.
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