DNA Reveals Enormous Adaptive Potential of Marine Microalga

Algae are some of the most successful species on our planet. Now, scientists may have discovered why one microalga has had such global success. They've sequenced the genome of the calcified alga Emiliania huxleyi and have learned more about its enormous adaptive potential.

The alga is tiny--only five thousandths of a millimeter in size. In fact, it looks a bit like a ball with pineapple rings stuck to its surface. While it may not look like much, though, this microalga is one of the most interesting organisms in the oceans. It helped create the chalk cliffs of Dover--the calcified remains of this alga built up over time to form the stunning landscape that we see today.

Yet this microalga doesn't just change landscapes. It also may be keeping Earth cool. The alga absorbs a prodigious amount of carbon from the atmosphere through photosynthesis and through the production of their calcified platelets.

So what did the researchers find when they sequenced the genome of this tiny, but vastly important species? It turns out that the genome was more of a surprise than they expected.

"The Ehux genome is incredibly variable. For example, if the genetic information of two humans is compared, an agreement of about 99 percent is found," said Uwe John, one of the researchers, in a news release. "However if, for example, we take two Ehux strains from different ocean regions, we find a degree of similarity of only 70 or 80 percent."

These findings suggest that while all of the algae possess a certain basic set of genes, there are supplemental genes which are interchangeable to a certain extent. These "extra" genes allow the algae to adapt to different climates and situations.

"Ehux can live almost everywhere at the ocean surface because the entirety of all genetic information of this species is huge as compared to other unicellular organisms, and this is probably the reason why it is able to quickly adjust to many possible conditions and to be successful in virtually all oceans of the world," said Klaus Valentin, one of the researchers, in a news release.

The findings help explain how this species has been so successful over the years. Currently, researchers plan to investigate the alga further, finding out how it reacts to different living conditions.