The Axolotl is a most unusual animal. A salamander, it has
evolved to remain in its larval stage throughout its life.
Since it lives only in one high altitude freshwater lake -
Lake Xochimilco in Mexico City - it does not need to
metamorph into an adult to live on land and keeps its gills
and baby-like features all its life. Leucistic individuals
(centre above) are common in captivity.
Because it retains these larval attributes, it is able to
regenerate lost limbs and damaged body parts. However, it
also reproduces young itself in this larval stage.
The Axolotl is critically endangered in the wild, threats
including reduction and pollution of the lake (it also
previously lived in Mexico City's Lake Chalco before that
was drained to reduce flooding of the city), introduction of
foreign fish which eat its young and its prey, and hunting
by humans for food and the pet trade.