lowerbloods were more or less used for breeding in ancient times, while highbloods were more or less the 'hunters' or 'protectors'. The blood spectrum caste originates in this. Because of their duties, it was only natural that lower blooded trolls were more calm and stable, and due to their breeding duties and jobs of taking care of the young. Whereas highbloods, made for battle, were far more hardy and violent.

Lowerbloods were more typically female and thus had more developed nooks than highbloods, who were typically male and had more developed bulges than lowbloods. Though ever since breeding techniques have included the mothergrub, this becomes less and less prevalent. An example being that a blue blood female will have a more developed bulge than a yellow blooded female, but it would not be as developed as a male troll of the same blood caste. The same goes for males, only vice versa.