Fish Adapts To Freshwater In Only Fifty Years

Some may think that evolution takes place over millions of years. According to scientists, a published study reveals that, in 1964, an Alaskan earthquake, which measured 9.2 in magnitude, forced tiny saltwater fish into fresh water in only fifty years.

“That is so sad that the earthquake forced them out of their usual habitat to an unknown place that was harming them,” junior Pierre Richard said.

After the earthquake happened, populations of fish were stranded by an uplift in freshwater ponds. The Threespine Sickleback fish experienced gene changes as well as changes in their visible appearance, such as eyes, shape, color, bone size, and body armor due to the change to freshwater. The fish evolved into a total of three different species.

“It is truly amazing how the Sickleback fish can adapt so quickly to stay alive,” senior Hannah Brunette said.

Thirteen thousand years ago, when glaciers receded, there were similar changes to the same species who were forced to exist in freshwater. The fish now have regions of their genomes alternatively honed for either freshwater or saltwater. This may have something to do with the fact that they are able to adapt so quickly in order to stay alive.

“It’s pretty rad that the fishies could adapt so quickly,” senior Shannon Tissera said.

“We’ve now moved the timescale of the evolution of sickleback fish to decades, and it may even be sooner than that. In some of the populations that we have studied, we found evidence of changes in fewer than even ten years. For the field, it indicates that evolutionary change can happen quickly, and this likely has been happening with other organisms as well,” a biology professor at the University of Oregon, William Cresko, said.

“It is neat that evolution allows fish to adapt so quckly,” junior Maya Stern said.

“They are quite lucky they were able to change so quickly in genes and physical appearance. Survival of the fittest!” junior Megan Majewski said.