Majiki are human. Majika abilities have never manifest in Gill people, even though they share the same DNA.
Majiki are about 80 percent female. Magic abilities have the potential to be in equal number of men and women, so it is thought that many men do not recognize these abilities and/or develop them.
Magic abilities manifest from birth; ignored abilities are often lost or go dormant.
Elemental Majiki are rare, and are 4 of 5 majiki born on the same date at the same time. The 5th one is the controller/king/queen, who the other 4 report to and who they ultimately work for. The past two controllers have refused the job, and one of the 4 elemental's has taken up the cause, with dire consequences to all of them. Without a seperate controller, the elementals become trapped. The existance of Atlantis does not suffer, but the world as a whole does. Global impacts are slow to make significant problems, but if it happens again, many more will suffer.