Read through all of these comments if you have the time: blah blah blah. If not, a key piece of evidence was an interview with Shinkawa, the character designer of Snake, saying that Snake dyes his hair. Here's a Shinkawa drawing of Snake with his natural hair colour: the original design for Pliskin in MGS2.
Now people also state, in regards to number two, that Snake dyes his hair so he would not be mistaken as Liquid Snake. He DID cut his hair in Metal Gear Solid because of this. However, while he does request a pair of scissors in the Metal Gear Solid briefing and cuts his hair, he doesn't ask for any hair dye.
Solid Snake's hair colour is debated to be blonde, brown, or black Solid Snake's hair colour has been the subject of much debate among fans of the Metal Gear series, with some arguing that his hair is blonde, while others claim it is brown or black. besides Snake looking like he has long blonde hair, Colonel Campbell says outside of skin tone, Solid and Liquid are exact duplicates He also has a black hole for a dick and a grey submarine has red walls. The briefing doesn't show the real colors of s***.
You can look like an exact duplicate of someone while having a different hair color. Hair color is superfluous in war, so it can be left to chance during the process of Genetic Artificial Alteration. In these way liquid is the superior/dominant clone in soldier genes term but still be blonde while snake is recessive/ "inferior".
Remember have a recessive gene do not means it's a flaw. Snake's hair colour has been the subject of much discussion among fans of the Metal Gear Solid series. Some claim that Snake is a natural blonde, citing early concept art and his appearance in MGS1's briefing as evidence.
However, others argue that Snake's hair is actually brown or black and that the lighting in certain scenes or the art style of the briefings made it appear blonde. It has. In the post I made about Shinkawa's Q&A, he says that Snake does dye his hair brown/black, but says that Plisken's hair color would be his natural hair (mild brown).
Snake Brothers' Natural Hair Color? Has anyone done out the punnet squares for the snake brothers' hair? I think that canonically, naked snake has to have one blonde gene and one brown hair gene, right? So, if Liquid has his dominant genes, he must be naturally brown haired, but dyes his hair blonde for fun, right? But he's already blonde in MGS5? About this item A highly luxurious natural snake hair oil which is has many benefits for your hair. Snake oil softens the hair in addition to fighting against dandruff, activate the hair growth. And I don't tell you about the gorgeous smell it emits! A real delight! Real Ginseng - this powerful ingredient helps to improve blood circulation, strengthen the immune system, and reduce hair loss.
It was an artistic choice to make up for the monochrome color scheme. The fact that any time after that, which is strictly optional to watch, by the way, Solid Snake appears with dark hair aside from when he ages prematurely should put this debate to rest. Snake has dark hair, end of story.