User blog comment:Lord Loss/Monster Hunter Theory... Blog/@comment-4775842-20120602160611/@comment-98.239.119.38-20120602225341

its even BETTER explained by agnaktor and barroth who have physical differences compared to their non subspecies cousins, the larger crown for the barroth sub and the beak/body size for the agna sub as well as elemental weaknesses and coloration showing the adaptation of these subspecies to their new environments

as far as monsters like gypceros and purple gypceros or yian kut ku and its blue brother, they're probably just pallette swaps made by lazy folk