Tuesday, August 17, 2010

The Incredible Axolotl



Here is a photo of my latest and weirdest pet: A GFP leucistic axolotl. Behind all that jargon is a fascinating story. The axolotl is a larval form of a certain salamander. Just like frogs have larval forms of tadpoles, and butterflies have larval forms of caterpillars, salamanders have larval forms which are aquatic creatures with feathery gills, a finned tail, and no eyelids. But axolotls are unique in that they are able to breed while in larval form; in fact, under normal conditions, they never metamorphose into adults.

This particular axolotl is a leucistic variety, which means that it is a mutation that lacks pigment (wild colored axolotls are dark in color). But there's something even more unusual about it. It is from a variety that has been genetically combined with GFP, a Fluorescent Green Protein from a jellyfish, which makes it glow bright green under ultraviolet light, as you can see in this picture.



Why were axolotls genetically modified in this way? It wasn't for the shtick of it. Instead, it relates to yet another amazing aspect of them. My axolotl had one his legs eaten by his tankmate. But within a few days, he had grown a new one that looked indistinguishable from the others. Axolotls were modified with the GFP protein in order that parts of GFP axolotls can be transplanted onto other axolotls and researchers can use ultraviolet light to track cellular generation - read this article for the full story.

Amazing! That's why I love the animal kingdom - there always something incredible to discover.