The only reason I know about this pattern is because I originally thought that my 3' male BP was a 'black back'. After sending pics to Adam Wysocki (he's around here some where, I'll let him know about this thread), I found it that he isn't because of 2 bands on him that break up the continuous black vertibral stripe. Adam said it it is rarely genetic, it just turns up. Some BPs have a brown/gold stripe on the spine instead of the black one.Originally Posted by Aza