If you enjoy your salmon meaty, or your battered cod to be the size of your arm, it might be time to start taking the bus instead of driving everywhere. A new study shows that increasing water temperature across the world are leading to smaller and smaller fish.

It is all to do with gas solubility in water—those who can remember GCSE chemistry will remember that the solubility of oxygen decreases as water temperature rises. As the ocean temperatures rise, there is less oxygen in the water for the fish to filter through their gills. On top of this, the warmer water also increases the metabolism of the fish—they burn through their energy quicker. The combination of both of these means that fish simply do not have the capacity to function as they get larger; they are using up more oxygen than normal, and there is less of it in the water to replace it. To combat this, fish are getting to a certain size, and then simply not getting any bigger.

This also has an effect up the food chain—the fish at the lower end of the food chain aren’t getting any bigger, and so the fish feasting on them are having to do with increasingly smaller meals, which unsurprisingly, stunts their growth.

The effect of humans on wildlife, both directly and indirectly, should be something that students hoping to study Biology or Natural Sciences B are aware of and reading about. Students thinking about studying Chemistry should look at solubility curves and understand the differences between solid and gas solubility. HSPS students should look at current political drives towards global warming, and how important America’s contribution to it is. 

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