Intrepid imaginaut (1970940): "Why do you think neanderthals had dark hair and brown eyes? Doesn't it seem a little odd that the only place you can find blonde hair, red hair, blue or green eyes and white skin also happens to be the same location that the neanderthals were mostly last seen in?"
Because
"A team at the University of Copenhagen have tracked down a genetic mutation which took place 6-10,000 years ago and is the cause of the eye colour of all blue-eyed humans alive on the planet today. [...] Originally, we all had brown eyes”, said Professor Eiberg from the Department of Cellular and Molecular Medicine. “But a genetic mutation affecting the OCA2 gene in our chromosomes resulted in the creation of a “switch”, which literally “turned off” the ability to produce brown eyes”. The OCA2 gene codes for the so-called P protein, which is involved in the production of melanin, the pigment that gives colour to our hair, eyes and skin. The “switch”, which is located in the gene adjacent to OCA2 does not, however, turn off the gene entirely, but rather limits its action to reducing the production of melanin in the iris – effectively “diluting” brown eyes to blue."
From http://www.sciencedaily.com/releases/2008/01/080130170343.htm
"Neanderthal extinction hypotheses are plausible explanations on how Neanderthals became extinct around 30,000 years ago."
From http://en.wikipedia.org/wiki/Neanderthal_extinction_hypotheses
So, the Neanderthals died out some 20,000 years _before_ there were blue eyes.
And no, the large dinosaurs like T-Rex weren't around at that time either.