Regeneration, Experimentation, & Conservation
Apart from being amazing pets, axolotls are important to humans in a variety of ways. First, they can regenerate body parts. This trait likely evolved as a counter to their cannibalistic nature. High population density and low food levels often lead them to turn on each other - a behavior we can observe even in captivity. Often legs and parts of tails are lost, and eventually regrow (although not always perfectly). This, of course, has great ramifications for the medical field. Research is currently underway that attempts to unlock the axolotls' secrets of regeneration in hopes of treating people who have lost limbs.
Like most amphibians, axolotls are very sensitive to environmental change. They are the proverbial canaries in the coal mines - if a habitat is affected negatively, they are the first to suffer. Worldwide, amphibians are declining due to increased chemicals in the environment, invasive species, human encroachment, land development, and climate change. Axolotls are near extinction in their native habitat, and thus serve as a warning. Unless we become more careful of how our actions affect the environment, more species will disappear as well.