Also, since the blood in your body is a lot darker, the veins appear darker. You may also notice that different sized blood vessels appear to be different colors. Another thing it can depend on is how you see color and how your brain perceives certain color against the color of your skin.
In 2015 the very popular name Allison, ranked the 39th Most Popular Girls Name in the United States. Presently one of the top 50 most popular, Allison has been less popular than the top 1000 in the past. It reached its highest popularity RANKING of #30 in 2009. However, the name was bestowed upon the greatest number of babies in 1994 with 8,150 occurrences.
How popular is Allison? Allison is a very prominent first name for females (#228 out of 4276, Top 5%) and also a very prominent last name for both adults and children (#590 out of 150436, Top 1%). (2000 U.S. Demographics)