Axolotls, Nature's Superheroes, Life at the Limits, RBG Centre, Royal Botanical Garden, Hamilton, ON
Excerpt from en.wikipedia.org/wiki/Axolotl:
The axolotl (Ambystoma mexicanum) is a paedomorphic salamander closely related to the tiger salamander. It is unusual among amphibians in that it reaches adulthood without undergoing metamorphosis. Instead of taking to the land, adults remain aquatic and gilled. The species was originally found in several lakes underlying what is now Mexico City, such as Lake Xochimilco and Lake Chalco. These lakes were drained by Spanish settlers after the conquest of the Aztec Empire, leading to the destruction of much of the axolotl's natural habitat.
A sexually mature adult axolotl, at age 18–27 months, ranges in length from 15 to 45 cm (6 to 18 in), although a size close to 23 cm (9 in) is most common and greater than 30 cm (12 in) is rare. Axolotls possess features typical of salamander larvae, including external gills and a caudal fin extending from behind the head to the vent. External gills are usually lost when salamander species mature into adulthood, although the axolotl maintains this feature.[15] This is due to their neoteny evolution, where axolotls are much more aquatic than other salamander species.
Their heads are wide, and their eyes are lidless. Their limbs are underdeveloped and possess long, thin digits. Males are identified by their swollen cloacae lined with papillae, while females are noticeable for their wider bodies full of eggs. Three pairs of external gill stalks (rami) originate behind their heads and are used to move oxygenated water. The external gill rami are lined with filaments (fimbriae) to increase surface area for gas exchange. Four-gill slits lined with gill rakers are hidden underneath the external gills, which prevent food from entering and allow particles to filter through.
Axolotls have barely visible vestigial teeth, which develop during metamorphosis. The primary method of feeding is by suction, during which their rakers interlock to close the gill slits. External gills are used for respiration, although buccal pumping (gulping air from the surface) may also be used to provide oxygen to their lungs.[15] Buccal pumping can occur in a two-stroke manner that pumps air from the mouth to the lungs, and with four-stroke that reverses this pathway with compression forces.
Axolotls exhibit diverse color variations driven by mutations in their pigmentation genes. These genes play a crucial role in determining the coloration of these unique creatures.
Axolotls, Nature's Superheroes, Life at the Limits, RBG Centre, Royal Botanical Garden, Hamilton, ON
Excerpt from en.wikipedia.org/wiki/Axolotl:
The axolotl (Ambystoma mexicanum) is a paedomorphic salamander closely related to the tiger salamander. It is unusual among amphibians in that it reaches adulthood without undergoing metamorphosis. Instead of taking to the land, adults remain aquatic and gilled. The species was originally found in several lakes underlying what is now Mexico City, such as Lake Xochimilco and Lake Chalco. These lakes were drained by Spanish settlers after the conquest of the Aztec Empire, leading to the destruction of much of the axolotl's natural habitat.
A sexually mature adult axolotl, at age 18–27 months, ranges in length from 15 to 45 cm (6 to 18 in), although a size close to 23 cm (9 in) is most common and greater than 30 cm (12 in) is rare. Axolotls possess features typical of salamander larvae, including external gills and a caudal fin extending from behind the head to the vent. External gills are usually lost when salamander species mature into adulthood, although the axolotl maintains this feature.[15] This is due to their neoteny evolution, where axolotls are much more aquatic than other salamander species.
Their heads are wide, and their eyes are lidless. Their limbs are underdeveloped and possess long, thin digits. Males are identified by their swollen cloacae lined with papillae, while females are noticeable for their wider bodies full of eggs. Three pairs of external gill stalks (rami) originate behind their heads and are used to move oxygenated water. The external gill rami are lined with filaments (fimbriae) to increase surface area for gas exchange. Four-gill slits lined with gill rakers are hidden underneath the external gills, which prevent food from entering and allow particles to filter through.
Axolotls have barely visible vestigial teeth, which develop during metamorphosis. The primary method of feeding is by suction, during which their rakers interlock to close the gill slits. External gills are used for respiration, although buccal pumping (gulping air from the surface) may also be used to provide oxygen to their lungs.[15] Buccal pumping can occur in a two-stroke manner that pumps air from the mouth to the lungs, and with four-stroke that reverses this pathway with compression forces.
Axolotls exhibit diverse color variations driven by mutations in their pigmentation genes. These genes play a crucial role in determining the coloration of these unique creatures.