Inheriting Those Acid-Washed Genes

Pictured: Eastern oyster (Crassostrea virginica).

Ocean Acidification Impacts Oysters’ Memory of Environmental Stress

We’re all pretty comfortable with the fact that we inherit our traits and characteristics from our parents in the form of DNA. We get a randomized half from mom, the other half from dad, and we’re the resulting mix. But that stuff is pretty set in stone – dependent on what our parents got from their parents and how the dice roll, right? Something like my mom moving from Albuquerque to NYC as a young woman isn’t going to make it more likely for my eyes to be blue – or could it? It turns out that environmental conditions experienced by our parents can impact the genes they pass on (though probably not as simply as influencing eye color). It’s all a bit complicated, so maybe we’ll get into it another time. Suffice to say it happens and it is veeerrrrry interesting to scientists at the University of Washington studying oysters.

The ocean, which you might recall is where oysters live, is changing quite rapidly. The climate crisis is not only causing the seas to heat up, but also become much more acidic. This is bad news for shellfish because it becomes much more difficult for them to grow their shells. It’s a problem that natural selection and evolution can totally handle… in hundreds of thousands of years. We’re already seeing pretty disastrous results from the current climate change so oysters have got maybe just a few decades to sort this out. Luckily, the researchers have identified at least one species of West coast oyster that is showing the kind of generational adaptation I previewed above. Given oysters can reproduce around two years old, there’s real potential for some species to get out of this bind.

In this study, researchers in Washington state exposed both Pacific oysters (Magallana gigas) and Olympia oysters (Ostrea lurida) to acidified conditions prior to spawning. The offspring of the Olympia oysters tended to fair better following their parents’ experience – displaying that generational adaptation capacity. The offspring of Pacific oysters, on the other hand, tended to fair worse. While that’s a less than ideal outcome, especially if you’re a Pacific oyster, there is a silver lining. Scientists can explore the differences between the two species to identify what might be causing the opposing impacts. Study of Olympia oysters may also aid in identifying other species of shellfish, marine animals, or animals and plants in general that possess similar capacity to adapt in the space of generations. Of course, the ideal would be for human beings to adapt how we live to be in line with a healthy planet. Fingers crossed we can be as speedy as Olympia oysters.

Johnny Venger has got his fingers crossed so hard he had to type this with his nose.