why it's almost impossible for axolotls completely live without water during their entire lifetime

Axolotls, or Ambystoma mexicanum, are amphibians that are adapted to live in water for various reasons tied to their biological characteristics and life processes:

1. Respiratory System: Axolotls primarily breathe through gills, which are specialized structures designed to extract oxygen from water. Their lungs are relatively underdeveloped compared to their gill system, making it difficult for them to breathe air effectively for extended periods.

2. Skin Functions: Axolotl skin is permeable and plays a significant role in respiration, osmoregulation (maintaining salt balance), and excretion. Keeping the skin moist is crucial for these functions to occur properly. Prolonged exposure to air can cause the skin to dry out, potentially leading to respiratory issues, skin damage, and infection.

3. Body Structure: Axolotls have a soft, delicate body that is more suited to the buoyancy provided by water than to support their body weight on land. Without water, they would struggle to move effectively, which can lead to physical stress and injury.

4. Habitat and Behavior: Axolotls are natural bottom dwellers in aquatic environments. Their natural behaviors, such as hunting for food and mating, are adapted to their aquatic habitat.

5. Life Cycle: Axolotls lay their eggs in water. The larvae hatch in an aquatic environment and undergo metamorphosis in water. They are fully aquatic throughout their entire life cycle, with no terrestrial stage.

6. Temperature Regulation: Like many amphibians, axolotls are ectothermic, meaning their body temperature is regulated by the environment. Water helps maintain a stable temperature, whereas air temperatures can fluctuate greatly, which can be detrimental to their health.

7. Predator Avoidance: In water, axolotls have a better chance of avoiding predators and hiding from threats compared to if they were on land.

While axolotls can survive short periods out of water, they are not designed to cope with a terrestrial environment over their entire lifetime. The physiological adaptations that make them unique and fascinating creatures in the water also make it nearly impossible for them to thrive outside of it.