Algae Found Living in Salamander Cells

Numerous monocles popped from experts' eye sockets when a research team announced the discovery of living algae inside cells of equally-alive salamanders. Arguably, this is the most advanced type of symbiosis ever discovered in vertebrates.

The discovery was made in the common spotted salamander, which wasn't especially remarkable for anything until now. Researchers never discovered this advanced degree of cross-species fusion in animals more complex than invertebrates.

The reason for this is actually very simple. Vertebrates, and higher animals in general, have immune systems that are programmed from birth to destroy invaders. Lower lifeforms, such as invertebrates, do not have this protective system, and this allows them to live in symbiosis with similar creatures.

According to the new research, it would appear that the algae in fact live within their salamander hosts since before the latter are even born. This raises the even more monocle-popping possibility that parent salamanders give birth to offspring that are already outfitted with the microorganisms.

“A large number of algae cells go inside the embryo. That was something we didn’t expect,” explains expert Ryan Kerney, who holds an appointment as a biologist at the Dalhousie University, in Canada.

The fact that algae lived with salamanders was well known since the 19th century. What was hidden from scientists was that the small organisms apparently endured within the embryos, and not outside them, as previously thought.

Other researches have shown that algae grow in symbiosis with baby salamanders during the earliest stages of embryo development. Scientists even managed to make sense of the collaboration – algae contribute to oxygenating the environment in which the amphibians grow.

Without the presence of algae, the embryos develop deformities, which endanger the evolutionary success of the salamanders. Therefore, from an evolutionary perspective, the symbiosis makes perfect sense, Wired reports.

What the new research team found was that algae did not only exist in the nutrient-rich environment surrounding the embryos, but rather inside the actual salamander as well. The microorganisms have their own distinct glow, which Kerney observed.

The initial discovery was announced in summer 2010, but it's only now that the experts are finally publishing all the details of their study. The paper appears in the April 5 issue of the esteemed journal Proceedings of the National Academy of Sciences (PNAS)