Only to the extent that they're producing offspring with other people who've continued to live in those same climates for extended periods of time. As our population becomes more mobile, that's a lot less certain. And if some generations of your family have lived in equatorial areas, and 10 generations later, they're living in five other places around the globe, you're not going to see consistent evolutionary pressures (especially considering the extent to which we mitigate those environmental pressures with modern technology). As I recall, skin tone is essentially an additive effect; there are some number of gene locii, and the more dark alleles you have between all of them, the darker your skin. I think the effects of direct heredity in that regard are going to be much, much more powerful than evolutionary selection. Given statistical distributions, there will continue to be variation, just as too people can produce a child that is either darker or lighter than them, depending on how those alleles sort out, but I think it'll gradually get closer to a normal distribution, rather than specific geographic areas that have consistently substantially darker or lighter skin. I'm talking very long-term here, obviously. Even if we all up and shuffled across the planet this minute, it'd take a while, and our interactions are still heavily within our own geographic regions, but it's been a continual process (hell, the vast majority of American citizens are examples of that), and I think it will continue in this direction pretty inevitably, barring societal collapse that stops the progressive increase of mobility.