Killifish: How This Mutant Fish Evolved to Survive in Toxic Polluted Waters

Despite the consequences of modern human civilization, nature still finds a way to adapt and survive. A team of researchers from the University of California, Davis has found that the Atlantic Killifish has evolved to adapt to estuaries containing toxic polluted waters.

According to the study published in the journal Science, the researchers have observed that populations of Atlantic killifish have adapted to live and survive in four urban estuaries, where the water has levels of pollution that's deadly to normal fish.

To identify how the Atlantic killifish has done it, the answer lies on their genes. The scientists examined 384 killifish from the four estuaries to determine how this species have changed genetically in order to survive in their habitat.

Results showed that the killifish showed has a "high degree of genetic variation" compared to any vertebrate -- even humans. EurekAlert notes that the higher the genetic diversity a species contains, the faster it can evolve and quicklu adapt to its environment. And in the case of the Atlantic killifish, they are 8,000 times more resistnat to lethal levels of pollution than any other kinds of fish. This shows that this species can adapt and survive in radically changing environments.

"If we know the kinds of genes that can confer sensitivity in another vertebrate animal like us, perhaps we can understand how different humans, with their own mutations in these important genes, might react to these chemicals," said lead author Andrew Whitehead, associate professor in the UC Davis Department of Environmental Toxicology.

Whitehead further says that despite this discovery, it is still unfortunate that the species that need more protection or preservation does not have high levels of genetic diversity to evolve and adapt quickly.

"This study shows that different populations of Atlantic killifish exposed to toxic pollution evolve tolerance to that pollution through changes in one molecular pathway. This pathway may play a similar role in many animals exposed to pollutants, with slightly different adaptations in response to different toxicants," said George Gilchrist, program director in the National Science Foundation's Division of Environmental Biology.