31 Axolotl Facts: Regeneration, Habitat & Biology

A salamander with lasting juvenile features: facts 1–9

• 1. The axolotl’s scientific name is Ambystoma mexicanum.
• 2. It belongs to the salamanders, within the amphibian class.
• 3. Axolotls are members of the mole salamander genus Ambystoma.
• 4. They normally retain external gills as adults instead of completing the typical salamander transformation.
• 5. Retaining juvenile features into adulthood is called paedomorphosis; neoteny is the term often used for axolotls.
• 6. Those feathery structures extending from the head are gills, not decorative horns.
• 7. Axolotls can also exchange gases through their skin and have lungs.
• 8. They reach reproductive maturity despite retaining their larval-looking body.
• 9. Rare or experimentally induced metamorphosis is possible; trying to force it is not responsible pet care.

Regeneration and research: facts 10–19

• 10. Axolotls can regrow lost limbs with bone, muscle, nerves and skin.
• 11. A regrowing limb develops a blastema, a mass of cells involved in rebuilding the missing structures.
• 12. The animal can regenerate a tail as well as limbs.
• 13. Research has documented regeneration of portions of spinal cord tissue.
• 14. Studies have also examined repair or regeneration in parts of the heart and brain.
• 15. Complex regeneration is not the same as merely closing a wound.
• 16. Normal successful limb regeneration can restore structures without the prominent scarring associated with many mammalian injuries.
• 17. Nerves play important roles in limb regeneration.
• 18. The axolotl genome is roughly ten times the size of the human genome; a larger genome does not imply greater intelligence.
• 19. Genome resources help researchers investigate which genes and cells participate in regeneration.

Home, appearance and survival: facts 20–31

• 20. Axolotls are native to freshwater habitats around Mexico City, not oceans.
• 21. Their historical habitat included Lakes Xochimilco and Chalco.
• 22. Remaining wild habitat is associated with the Xochimilco canal system.
• 23. Wild axolotls are typically dark or mottled rather than the pale pink appearance familiar from captivity.
• 24. Leucistic captive axolotls can have pale bodies and dark eyes; leucism is not automatically the same as albinism.
• 25. Wild axolotls are classified as Critically Endangered.
• 26. Urban development and pollution have damaged their habitat.
• 27. Introduced fish are another pressure on wild populations.
• 28. Axolotls are carnivores, eating small aquatic prey rather than grazing on plants.
• 29. They draw food into the mouth using suction rather than chewing like a human.
• 30. Captive populations can be numerous while the wild population remains severely threatened.
• 31. Clean, cool freshwater is essential in captivity; legal ownership rules and specialist care requirements vary by location.

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