Remember that train in the old western with the villain stoking the fires in the engine room as the locomotive heads towards the cliff. Well, in a sense, that may be just what’s on track for the world’s oceans due to a bizarre response to climate change exhibited by a key group of ocean bacteria known as Trichodesmium.
Trichodesmium, referred to by scientists as Tricho, are one of the few organisms in the ocean that fix atmospheric nitrogen gas and make it available to other living things. This makes them crucial to every form of sea life that requires nitrogen, everything from Algae to Orcas.
But a study from reasearchers at USC and the Woods Hole Oceanographic Institution (WHOI) shows that increased carbon dioxide in ocean water due to climate change could eventually send the tiny Tricho into unbridled reproductive overdrive consuming all the available resources they, and most life in the ocean need to survive.
By breeding hundreds of generations of the bacteria over the course of nearly five years in the high-carbon dioxide ocean conditions predicted for the year 2100, researchers found that the Tricho first grew more rapidly and produced more nitrogen and then, inexpicably, failed to return to their regular growth and consumption rates even when returned to normal conditions. This apparently irreversible adaptation was obviously alarming for the marine biologists.
“Losing the ability to regulate your growth rate is not a healthy thing,” said David Hutchins, professor at the USC Dornsife College of Letters, Arts and Sciences. “The last thing you want is to be stuck with these high growth rates when there aren’t enough nutrients to go around. It’s a losing strategy in the struggle to survive.“