Sunday, December 11, 2016

A Mutation in the Killifish Enables it to Survive in Harmful Conditions

The Atlantic killifish is native to the Atlantic coast of the United States. A large amount of killifish live in the Lower Passaic Superfund site. The State of New Jersey prohibits people to eat fish from this site because they are contaminated by toxic leftovers of DDT and Agent Orange. These chemicals are strong enough to wipe out the entire population in the area; however, plenty of killifish are still living and thriving in the area. This is because the fish are somehow tolerant to the toxins in the water. 

A new study discovered that in just a few decades, separate populations of killifish adapted a mutation to survive in abnormally extreme conditions. The scientists of the study looked at the genomes of 384 populations and found that, in all populations, "one particular genetic pathway was the source of the pollution tolerance." Typically, harmful chemicals set off changes in the fish, causing death in adults and problems in embryos. Tolerant fish are barely affected by the chemicals; they can survive in conditions that are thousands of times more polluted than what sensitive fish die in. In killifish, like in all animals, a big genome is used to their advantage. Genetic differences allow for the mutation to actually be advantageous. The fish that did not have the mutation died, and the fish that had the mutation lived and reproduced. Smaller populations that were less genetically diverse died off. 

The scientist from this study suggest that many other species can adapt to survive in extreme conditions caused by pollution and climate change. They add that while some species can adapt, many species can not. As people of the world, we must take it upon ourselves to stop pollution before it is too late. Humans are just another animal that inhabit the Earth. It is not our planet to destroy. Ignorance has got the world to close to a breaking point in global warming. We have not always known that our industries are polluting the world, but know we do. We can no longer just stand by and watch the world far apart. Clearly, no one is capable of saving the world alone. However, everyone can contribute simple things such as recycling, using less water, and conserving energy to put us on the step in the right direction.


  1. It is interesting to see how marine wildlife can adapt to the conditions of the extremely polluted water. Even though this one species is able to adapt, not all species are able to do the same, which can lead to major species dying off.

  2. This is quite interesting because of how pollution is taking our planet and how the animals need to survive they adapt themselves. Pretty sad but cool at the same time