The Mexican salamander, or axolotl, is an especially unique amphibian in that it remains a fully aquatic creature in adulthood and retains its gills instead of growing lungs like most amphibians.
Axolotls are exceptionally easy to breed in captivity, and for this reason are studied extensively in such wide-ranging fields as heart defects and neural tube development. But perhaps the most fascinating feature is their ability to completely regenerate entire limbs, other appendages, and even brain sections when damaged.
Unfortunately, the wild axolotl’s habitat is limited to a few lakes in central Mexico, which are under stress due to rapid urban development along with the introduction of non-native predators to their natural habitat. Consequently, the axolotl has earned a categorization of “Critically Endangered” on global conservation lists.
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