Background
The authors write that "both ocean warming and acidification have been demonstrated to affect the growth, performance and reproductive success of calcifying invertebrates." However, they say that "relatively little is known regarding how such environmental change may affect interspecific interactions."

What was done
In exploring one example of a marine inter-species relationship - specifically, a predator-prey relationship - Landes and Zimmer separately studied green crabs (Carcinus maenas, the predators) and periwinkles (Littorina littorea, the prey) under conditions that mimicked either ambient seawater or warmed and acidified seawater (both separately and in combination) for a period of five months, after which the predators, their prey and the predator-prey interaction were screened for any differences that might have developed among the individuals exposed to the different treatments.

What was learned
The two researchers determined that "acidification negatively affected the closer-muscle length of the crusher chela and correspondingly the claw-strength increment in C. maenas," while "the effects of warming and/or acidification on L. littorea were less consistent but indicated weaker shells in response to acidification." And as might have been expected on the community level in light of these observations, they found "no evidence" that this specific predator-prey relationship would change in the future.

What it means
In light of their several findings, Landes and Zimmer conclude that "marine communities that are based on calcifying invertebrates may be less affected by warming and acidification than would be expected from species-specific responses to environmental change."