When the Aztecs established the Valley of Mexico in the 13th century, they discovered a vast salamander dwelling in the lake around the island where they erected their capital, Tenochtitlán. The Aztecs gave the salamander the name “cute axolotl ” in honor of Xolotl, their deity of lightning and fire. Xolotl was thought to have turned into a salamander, among other forms, to escape being sacrificed so the sun and moon could move in the sky. He was finally arrested and executed.
In the same line, cute axolotls were routinely slain for food by the Aztecs and are still consumed today in Mexico. As a result of their low maintenance requirements and charming personalities, they’ve become one of the most popular pets in the world. The organisms’ unique regenerating powers have made biologists a fascinating research topic. But in their natural environment, the salamanders have practically gone.
Axolotls (Ambystoma mexicanum) are amphibians belonging to the solitary extant genus of the family Ambystomatidae. The Ambystoma genus, which includes the mole salamanders, has about 30 different salamander species.
Cute Axolotl Appearance
The axolotl seems unearthly, like a cartoon dragon sans wings. It has six fluffy exterior gills that jut out around the head like a crown. A largemouth and tiny, lidless eyes on an otherwise featureless face give A. mexicanum a look of eternal happiness. In sum, they’re charming little animals.
While they need specific care requirements, these amphibians are resilient and straightforward to raise. They’re not only novelty pets but fantastic creatures to care for and enjoy.
Cute Axolotls can grow on average to 9 inches (20 centimeters). However, some have grown to more than 12 inches (30 cm) long. In captivity, the salamanders survive on average for 5 to 6 years, although some have lived for up to 17 years, according to the University of Liverpool’s The Animal Ageing and Longevity Database.
Over time, the form gets more froglike, and legs emerge. As it grows, the tadpole becomes ever more reliant upon gulps of surface air until its portions are wholly formed, and the tail recedes and is no longer discernible. The tadpole subsequently exits the water, either lingering about its edges as a small frog or venturing further away as a juvenile toad. Besides evident physical changes, there are unique physiological changes that occur. A tadpole’s gills go, and lungs form. Its digestive system also transforms, from a long coil system capable of breaking down and subsisting on algae to a more expanded system that can digest meat and insects.
Salamanders and newts are likewise amphibians, and they undergo a similar metamorphosis. In reality, the familiar tiger salamander (A. tigrinum) belongs to the Ambystoma genus and resembles the cute axolotl in its juvenile form. However, salamander larvae seem superficial, more like adults, and their transformation is less dramatic. Many salamander larvae have entire legs, while other species acquire them later. A critical distinction between frog tadpoles and salamander larvae comes in the shape of big, visible, external gills. Looking at a tadpole, the gills are not prominent, but in most species of salamander larvae, they are. As the salamander larvae age, their gills evaporate, and other physiological changes occur, including the reproductive system’s development.
In certain salamander species, the larvae may stay in the water for several years if circumstances on land are not favorable. In a few of these species, they may also reach a stage termed neoteny, which means “extended youth.” In this example, people maintain their “youthful” features—precisely, gills—yet reproduce. This is partial neoteny, in which individuals appear pretty similar to the adults but nevertheless maintain some of their larval traits (e.g., a salamander with short gills), or total neoteny, in which the individual is virtually suspended in a larval state yet capable of reproduction. The specific mechanisms that generate neoteny in salamander larvae are unknown; some individuals will develop into this stage while others will not.
There are a few documented cases in which mature forms never appear. Instead, juveniles retain their gills and other juvenile traits as they develop into a reproductive adult that is an exact replica of the child, although much more significant in stature. The axolotl is the most well-known (A. mexicanum).
Is There a Wide Variety of Cute Axolotls to Choose From?
There is no specific or defined quantity of color variants for this beautiful species.
In the wild, you may often find brown or tanned cute axolotls with some golden particles, occasionally with a greenish undertone. Axolotls in the wild are becoming rarer, which is a real shame. In fact, in 2010, they were believed virtually extinct!
Intelligent genetic engineering is responsible for a wide variety, and most of them are produced under laboratory conditions. There are now several mutant kinds and morphs to choose from as a consequence.
Due to increased demand from pet owners, mutant morphs are becoming more widespread. You may discover unusual or uncommon colors and even some sporadic color variants.
Why Do Axolotls Have Such a Wide Variety of Colors?
What, therefore, accounts for this wide range of variance among cute axolotls species? To answer that, you have to go a little further into genetics.
The pigment cells called chromatophores determine the color of an axolotl. To produce various shades of color pigmentation, chromatophores may be divided into three categories:
Black or brown pigmentation is caused by the melanophores, which contain Eumelanin.
Xanthophores: Contains Carotenoids and Pteridines, creating a yellow and red coloring.
Crystallized purines in iridophores provide a coloration like a soap bubble (Iridescence).
Chromatophores, pigment cells, have 14 sets of 28 chromosomes apiece, each from the mother and the father. Various and unusual axolotl color types may be formed with innovative crossover activity.
That’s why we may encounter such uncommon variations of axolotl mutant these days.
Where do axolotls live?
Wild axolotls dwell solely in the marshy remains of Lake Xochimilco and the canals leading to it on the southern fringe of Mexico City. Axolotls formerly resided at Lake Chalco, another of Mexico City’s five “big lakes” where the ancient Aztecs dwelt. According to NBC News, except for Xochimilco, all of these lakes had been drained by the 1970s to avoid floods and allow urban growth.
Because of their carnivorous diet, axolotls have long been considered the top predators in their ecosystems. They grasp everything they can snatch: Mollusks, fish, and arthropods like insects and spiders. You may find them eating each other. Although a JSTOR Daily story claims that in the 1970s and 1980s, the UN Food and Agriculture Organization introduced tilapia and carp fish to the salamander habitat to give local residents more protein, These fish prey on baby axolotls and pose a danger to the salamanders since they are invasive.
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The axolotl mating dance
Axolotl reproduction begins with dancing — literally. According to the University of Michigan’s Animal Diversity Web, salamanders dance in a circle after nudging and stroking one another’s urogenital entrance, known as the cloaca. Next, the male makes his exit by shuffling his tail in the air, which attracts the female’s attention. As the two dance partners step together, the male drops a tiny white capsule filled with sperm called a spermatophore. With the female in tow, the male goes ahead till the female barely skirts over the spermatophore and takes it up with her cloaca.
Axolotls go through this courting yearly, often from March through June. With the courting dance behind her, the female axolotl will individually attach her 100-300 jelly-coated eggs to water plants or rocks. Around 10 to 14 days later, the eggs hatch, and the young fend for themselves. Axolotls reach sexual maturity after approximately a year of development.
Unlike other amphibians, axolotls never metamorphosis into lung-breathing, terrestrial adults. American evolutionary scientist Stephen Jay Gould defined salamanders as “sexually mature tadpoles” because they eternally preserve their juvenile characteristics: A totally aquatic existence, a finned tail, and frilly gills. This evolutionary feature of “everlasting youth” is termed paedomorphosis or neoteny. Axolotl metamorphosis may be induced in the laboratory by administering thyroid hormones to the animals, although this seldom happens in the wild.
Are axolotls endangered?
cute Axolotls are listed as severely endangered by the International Union for the Conservation of Nature and Natural Resources, and their number is in decline. Surveys in 1998 and 2008 indicated that the population density has declined from around 6,000 inhabitants per square kilometer to 100 individuals per square kilometer. A more recent study in 2015 revealed roughly 35 persons per square kilometer.
The extinction of the species has been exacerbated by pollution. Poor waste restrictions and increased tourism in Mexico City mean that garbage, plastics, heavy metals, and excessive amounts of ammonia leaked from waste-treatment facilities choke the waterways where the salamanders reside.
A sizable captive population occurs in research facilities across the globe, amounting to several thousand people. But these salamanders originate from 33 individuals sent to Paris from Xochimilco, Mexico. Therefore the population is significantly inbred.
Cute Axolotls in research
Among the cute axolotl’s specific skills is its capacity to regenerate practically any bodily part — feet, legs, arms, tails, even pieces of the heart and brain. Their regenerative abilities don’t end there. All types of organs, including eyeballs, maybe transplanted between axolotls without rejection by the recipient body’s immune system. In 1968, researchers revealed that they could even transplant the skull of one axolotl to another axolotl, and it functioned correctly. The combination of these qualities made axolotls excellent model organisms for scientists.
In 2018, researchers uncovered another mystery about axolotls: Their vast genome. It is estimated that the cute axolotl genome contains roughly 32 billion pairs of DNA nucleotides, dwarfing the human genome, which is about a factor of ten smaller. Researchers delve into the DNA to unearth the mysteries underlying the cute axolotl’s healing ability.
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