Background
The authors write that "marine phytoplankton have many obvious characteristics, such as rapid cell division rates and large population sizes, that give them the capacity to evolve in response to global change on timescales of weeks, months or decades." However, they note that "few studies directly investigate if this adaptive potential is likely to be realized." And, hence, they go on to do so, in a comprehensive review of the pertinent scientific literature.

What was done
Collins et al., as they describe it, "first provide background on global change in oceans, and then review studies aimed at understanding how marine phytoplankton communities may evolve in response to global change."

What was learned
Quoting the three researchers, "the simplest interpretation of laboratory selection experiments to date is that most taxa can evolve by genetic change within species, using standing genetic variation, mutation or both," while noting that "in natural populations, the high standing genetic variation further suggests a high potential for evolutionary responses to climate change." And they additionally note that in still more subject-focused instances "current evolution experiments suggest that some taxa can evolve in response to ocean acidification."

What it means
In the concluding paragraph of their paper, Collins et al. state that "every indication so far suggests that marine phytoplankton have the potential to evolve in response to global change, both by sorting standing variation in fitness and by using de novo mutation." And, therefore, they say that the likelihood that "large phytoplankton populations can evolve on timescales of years or decades is not surprising."