Salamander embryos go green
I found out today that some salamander embryos have symbiotic algae. The algae use the salamander’s waste products as fertiliser, and the baby salamander (probably) benefits from the oxygen they produce by photosynthesising. That’s pretty cool, but it’s not really news, since the association was discovered about 120 years ago.
What is new is a finding by a Canadian & American group, that the algae actually get inside the salamander’s cells. That apparently makes it the first known case of a vertebrate having a symbiont inside its cells. People had suggested that vertebrate immune systems were too protective to let that happen. Salamanders’ immune systems aren’t that advanced by vertebrate standards, though, which might be why the symbiotic algae can get in. Or it might be because the immune systems of the embryos are still developing.
The researchers also found some hints that the algae can be passed down from the mother, but they’re not so confident about that.