Global climate changes are typically connected to negative impacts on the Earth's ecosystems, but a new Florida State University study reveals that it may actually be setting up the Pacific Northwest for greater species diversity, which can be both positive and negative, depending on the species in question.

Scientists have been closely monitoring the effects of increased carbon dioxide levels in our water, which has been linked to climate change, and the current team further explored these effects by examining old experiments on species diversity and the nature of the competition between them.

These analyses led to the recognition of physical changes in algae skeletal structures, prompting the team to see if continued ocean acidification, which refers to the increase of carbon dioxide in water, affected species interactions; the results showed that it does.

"Ocean acidification is promoting competition and no one is dominating," said Sophie McCoy, who headed the study.

McCoy and her team examined types of coralline algae, a hard skeletal algae that is important for the proper functioning of marine ecosystems and a food source for numerous sea creatures such as sea urchins and mollusks. These species were an ideal choice due to the wealth of historical data available on them, allowing the team to closely examine changes over time.

The results revealed that over time, as carbon dioxide levels have grown, so too has competition among species, leading to an increase in diversity. Furthermore, the historical data revealed that these increases in competitive interactions developed over a long period of time, as opposed to suddenly.

What does this mean for ecologists and conservationists? Future studies should look at early signs of changing interactions, and if these changes look to have negative effects in the future, they should start looking at potential corrective measures.

"If you're looking for these early warning signs, you might see these changes in interactions and catch it before a big change happens," McCoy said. "I think it's important to understand that there are changes in how ecological communities are being put together or how they function, to be aware that how we think of communities working or responding to stress is changing.  This could lead to reduced ability of a community to buffer change."

The findings were published in the Mar. 2 issue of the Proceedings of the Royal Society B: Biological Sciences.