axolotls

Axolotls, scientifically known as Ambystoma mexicanum, are a neotenic salamander native to Lake Xochimilco and the surrounding waters near Mexico City. Unlike most salamanders, axolotls retain juvenile features such as gills and an aquatic lifestyle throughout life, a condition known as neoteny.

Adult axolotls have a broad head, lidless eyes, and distinctive feathery external gills that extend from either side of the head. A dorsal fin runs from the back to the tail, and the body is typically stout. In captivity they occur in several color forms, including wild-type (dark body with speckling), leucistic, albino, and melanoid varieties.

Life cycle: In the wild they inhabit cool, oxygen-rich canals and lakes. Axolotls are aquatic throughout their life and reproduce in water. They reach sexual maturity around 12 to 18 months in captivity. Males release spermatophores; females collect them and lay eggs that adhere to vegetation. Larvae hatch with external gills and grow into adults without metamorphosis under normal conditions; metamorphosis can be induced experimentally by hormonal or environmental changes but is uncommon in nature.

Diet and behavior: They are carnivorous, feeding on small prey such as worms, insects, crustaceans, and small fish. In captivity they accept prepared pellets as well. They are generally nocturnal and tolerate a range of water conditions if kept clean.

Regeneration and research: Axolotls are renowned for their regenerative capacity, able to replace limbs, spinal cord, heart tissue, and parts of the brain. Their biology makes them valuable model organisms for studies of development, regeneration, and genetics.

Conservation: In the wild, axolotls are critically endangered, primarily due to habitat degradation, pollution, and introduction of invasive species in the Mexican highlands. They persist in small remnants of the original lake-system. Many individuals in zoos and laboratories are captive-bred; conservation programs aim to maintain genetic diversity and reintroduction prospects where feasible.