Updates‎ > ‎

2016-12-09. Rapid Evolution Saved This Fish From Pollution, Study Says.

posted Dec 15, 2016, 2:43 PM by Alan Gould
By Joanna Klein, The New York Times. For GSS Losing Biodiversity chapter 4. Excerpt: The State of New Jersey says you can’t eat the fish or shellfish from the Lower Passaic River and Newark Bay. That’s because they’re living in the Diamond Alkali Superfund Site, where toxic leftovers from the manufacture of chemicals like DDT and the infamous Agent Orange oozed into surrounding waterways to be taken up by the animals that inhabited them. It’s an evolutionary miracle some of these animals are even alive. ...A fish that adapted to survive in this water shows evolution at its finest, according to a study published Thursday in Science. The Atlantic killifish is a slippery sliver of silver about the size of a fat finger and as common as the minnow. Starting in the late 1990s, researchers became aware that the fish was tolerant of the toxic waters at the Lower Passaic Superfund site and at least three other highly polluted areas along the Atlantic coastline. The new study found that over just a few decades, distinct populations of killifish independently developed similar genetic adaptations that make life possible in the most unlikely environments. The findings show that evolution doesn’t have to start in one place to be repeated. ...Normally, toxic chemicals like dioxins and polychlorinated biphenyls, or PCBs, set off a number of changes inside sensitive fish that interfere not just with the survival of adults, but also with the development of their embryos. But in the tolerant fish, the trigger for those changes is turned off, allowing some fish to survive levels of PCBs thousands of times higher than the levels affecting sensitive fish....  http://www.nytimes.com/2016/12/09/science/atlantic-killifish-evolution-pollution.html