Say hello to Gorbachev, a highly unusual Australian lungfish.
Lungfish are, in themselves, a peculiar animal which retain their prehistoric ability to breathe air. And the Australian lungfish is the most peculiar of all the lungfish - which live only in Africa, South America and Australia - because while its counterparts have two lungs, the Australian lungfish only has one.
If you think that's some strange stuff, then wait until you meet Sydney Aquarium's Gorbachev. Gorbachev is estimated to be at least 20 years old. He came to Sydney Aquarium when it first opened and lived with all the other typically grey lungfish. However, at around five years old, something strange began to happen - Gorbachev started to turn yellow.
This continued over the next ten years until he became the brilliant colour he is now - an unusual occurrence rarely sighted or documented the world over!