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Mole salamander

life science Maturity 7-9 Next article →

Mole salamanders belong to the genus Ambystoma. They are a group of advanced salamanders found only in North America.

Mole Salamander (Ambystoma talpoideum) (39994300015)
Mole Salamander (Ambystoma talpoideum) (39994300015)

These animals are very important to biological research. The axolotl is a famous member of this group. Scientists study it to understand how bodies change and grow. Other species, like the tiger salamander, are very common. In fact, the tiger salamander is the official amphibian for four US states.

Barred Tiger Salamander Tennoji
Barred Tiger Salamander Tennoji

Most adult mole salamanders live a life on land. They spend much of their time in underground burrows. They might dig these holes themselves or use abandoned ones. They are solitary animals that eat various invertebrates.

Blue Spotted Salamander (Ambystoma laterale) (44133419344)
Blue Spotted Salamander (Ambystoma laterale) (44133419344)

While adults live on land, they must return to water to breed. All mole salamanders are oviparous, which means they lay eggs. They lay these eggs in large clumps within the water.

The life cycle of a mole salamander involves several stages. It begins with aquatic larvae that are branchiate. This means they have three pairs of external gills behind their heads. These larvae also have large caudal fins. These fins extend from the head to the tail and the cloacae. As they grow, they develop limbs with specific toe counts. Forearms have four toes, while hind legs have five toes.

Ambystoma barbouri 1
Ambystoma barbouri 1

Their eyes are wide-set and do not have true eyelids.

Many species undergo metamorphosis to transition from water to land. During this process, the gills and fins disappear. The skin, limbs, and tails become much thicker. The eyes develop eyelids to protect them on land. The lungs also become fully developed to allow for breathing air. However, some species are neotenic. This means they keep their larval forms even as adults.

Ajolote 1
Ajolote 1

The axolotl is the most famous neotenic example. These animals cannot produce thyroxine on their own. They can only undergo metamorphosis through an outside injection of this substance. This process usually shortens their lifespan.

There is also a unique group of all-female salamanders. These are known as unisexual populations. They are found across the Great Lakes and northeastern North America. These females use sperm from related species to start egg development. This process is called gynogenesis. They may also use a method called kleptogenesis. In this case, they incorporate parts of the sperm's genome into their offspring.

Ambystoma phylogeny
Ambystoma phylogeny

Their DNA can include parts from up to five different species. This includes the blue-spotted, Jefferson, small-mouthed, streamside, and tiger salamanders. Because of this, they are considered a cryptic species. This means they look very similar to the species they live near.

Scientists have studied the history of these animals for a long time. Johann Jakob von Tschudi named the genus Ambystoma in 1839.

Some people thought the name meant "to cram into the mouth." Others thought it was a mistake for the word "Amblystoma." There are currently 32 known species in the genus. One of the newest species discovered is A. bishopi. Researchers are still working to classify many of them. For example, they are still studying the tiger salamander complex. They want to know if certain groups are separate species or subspecies.

One of the most amazing things about mole salamanders is regeneration. The axolotl is a primary model for studying how limbs regrow. When a limb is lost, the animal forms a blastema. A blastema is a mass of highly proliferative cells. These cells are low in differentiation, meaning they are ready to become many things.

During this growth, the cells must repair their own DNA. They use a process called homologous recombination to fix double-strand breaks. This incredible ability helps scientists understand how cells repair themselves and build new body parts.

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🖼️ Images & Media (34)
File:Exhibit Museum of Natural History, Ann Arbor - IMG 9137.JPG
Exhibit Museum of Natural History, Ann...
File:Barred Tiger Salamander Tennoji.jpg
Barred Tiger Salamander Tennoji.jpg
File:Ambystoma phylogeny.jpg
Ambystoma phylogeny.jpg
File:Ambystoma altamirani cropped.jpg
Ambystoma altamirani cropped.jpg
File:Fl_mammals_en.svg
Fl_mammals_en.svg
File:Fl_mammals_cr.svg
Fl_mammals_cr.svg
File:Ambystoma andersoni.jpg
Ambystoma andersoni.jpg
File:Ringed Salamander (Ambystoma annulatum) (24088441718).jpg
Ringed Salamander (Ambystoma annulatum)...
File:Fl_mammals_lc.svg
Fl_mammals_lc.svg
File:Ambystoma barbouri 1.jpeg
Ambystoma barbouri 1.jpeg
File:Fl_mammals_nt.svg
Fl_mammals_nt.svg
File:Fl_mammals_vu.svg
Fl_mammals_vu.svg

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