A recent study was done on 400 Atlantic Killifish from a polluted/nonpolluted area. The study showed that they are "8,000 times more resistant" to pollution than any other fish studied (ScienceDaily). Scientist thought it could be genetic diversity but then discovered that the Atlantic Killifish already had a genetic variation for pollution, that allows them to adapt to such high polluted areas so quickly. While the other species are dying from the pollution or undergoing mutations (extra fin, 2 heads), the Atlantic Killifish comes out unharmed from all the pollution. There are not that many solutions to withstand pollution and this may be one of the limited adaptation to it.