Axolotl Introduction

The axolotl, sometimes called the Mexican walking fish, is a type of salamander native to two lakes in the vicinity of Mexico City. What makes the axolotl especially unique among amphibians is that it is neotenic. This means that, unlike other salamanders, the axolotl remains in a kind of larval stage for the duration of its life. Because it never undergoes metamorphosis, it keeps its frilly exterior gills and lives an aquatic lifestyle. Although they do develop small lungs, they are unable to live out of the water for any extended period of time. Because of their larval-like appearance, Axolotls are sometimes confused with young tiger salamanders, but they are a completely different species. The native habitat of the axolotl is diminishing rapidly due to draining and contamination, this threatens the axolotl and makes it difficult to study this unique animal in the wild. Most of what scientists know about axolotls comes from studies of lab population or pets. A four-month search was conducted in 2013 that found no living axolotls in the wild, but it is suspected that there are small and elusive axolotl populations, and axolotl shelters have been built to help provide adequate habitat. In terms of appearance, axolotls have wide faces with branching gill stalks on either side. Their body ends in a long flat tail which enables them to swim through their watery home. Their legs appear underdeveloped compared to other salamanders. While wild axolotls are dark greenish grey in colour, captive axolotls have been bred for lighter hues, and are often pinkish white with darker gills. A relatively young species, the axolotl has many strange and fascinating features that make it a puzzle for scientists. Axolotls do not heal by scarring and instead are able to regenerate their limbs, tails and even more complex tissue. To study this strange superpower, scientists have sequenced the entirety of the axolotl’s genetic code—the longest animal genome sequenced so far. Their many interesting and alien features make them an appealing pet for many people, but care must be taken to ensure that their unique needs are met in captivity.