This week we have the Pseudis paradoxa. It is common known as the paradoxical frog or shrinking frog. It is from South America.
The reason for the naming is because the species is abnormally large when it is a tadpole, usually up to 25cm (9.8in) long. However, when it turns into a frog, it shrinks into around 1/4 of its former length.
It is one of the only animal in the world that have babies bigger than the parents.