Genome complexity: raid epigenetic changes in fish (Introduction)

by David Turell , Wednesday, December 16, 2015, 01:07 (3045 days ago) @ David Turell

Environmental challenges have caused the stickleback fish to change and adapt. Same species but obvious changes in 50 years:-http://www.sciencedaily.com/releases/2015/12/151214165724.htm-"Evolution is usually thought of as occurring over long time periods, but it also can happen quickly. Consider a tiny fish whose transformation after the 1964 Alaskan earthquake was uncovered by University of Oregon scientists and their University of Alaska collaborators.-"The fish, seawater-native threespine stickleback, in just decades experienced changes in both their genes and visible external traits such as eyes, shape, color, bone size and body armor when they adapted to survive in fresh water. The earthquake -- 9.2 on the Richter scale and second highest ever recorded -- caused geological uplift that captured marine fish in newly formed freshwater ponds on islands in Prince William Sound and the Gulf of Alaska south of Anchorage.-***-"'And this is not just a plastic change, like becoming tan in the sun; the genome itself is being rapidly reshaped," she said. "Stickleback fish can adapt on this time scale because the species as a whole has evolved, over millions of years, a genetic bag of tricks for invading and surviving in new freshwater habitats. This hidden genetic diversity is always waiting for its chance, in the sea.'"-Comment: As with guppies, alterations can be quite rapid.