Salamander battles threat of extinction

Dubbed the "water monster" by the Aztecs, the axolotl salamander is battling extinction in the remnants of Mexico City's ancient lake, alarming scientists, who are hoping mankind can learn from the creature's ability to regenerate organs.

The salamander, whose colors vary from milky white to black and olive green, has survived in the Xochimilco canals since most of the lake was drained during the centuries following the Spanish conquest.

But the sprawling megacity of 20 million is taking its toll on a species that can also resist cancer and reproduce complex brain tissue.

Researchers have studied the salamander's cells in hope of grasping how to regenerate the organs and body parts of people suffering from malformations or accidents.

While the female salamander can lay 1,500 eggs four times a year, only 0.3 axolotls can be found per square kilo-meter, on average, compared with 1,000 in 1996, according to a study by National Autonomous University of Mexico.

Now, university scientists under the auspices of Britain's Kent University are striving to keep the legendary animal alive. They are trying to convince local farmers to stop using harmful pesticides and avoid growing nonnative plants near canals in the southern part of the city. In return, their vegetables will get an eco-friendly label that makes them more valuable.

About 10 farmers are adopting the program, which includes making the canals cleaner using aquatic plants.

So far, about 100 salamanders have been born in three experimental canals, said Horacio Mena, the project's coordinator. Salamanders are also breeding in labs.

But the locations of the breeding grounds have been kept secret to prevent the theft and sale of the creatures as pets or for medicinal purposes on the black market.

Mexican walking fish

Just 30 centimeters long, the salamanders - or "Mexican walking fish"-are carnivores with external gills. The species remains in larval form throughout its life.

With eyes that never shut because of a lack of lids, it never morphs into adult form, even though it can live up to 20 years in captivity and six years in the wild.

According to Aztec mythology, the salamander is the last reincarnation of the god of fire, Xolotl, who took the form after refusing to sacrifice himself with other deities at the launch of the age of the Fifth Sun, the era of the creation of mankind.

Nowadays it is becoming harder to find because the water in which it thrives is contaminated by urbanization, pesticides and trash left behind by legions of visitors lounging in the canals on colorful rafts, biologist Cristina Ayala told AFP.

The salamanders also have had to contend with thou-sands of carp, a fish the government introduced to the canals over the years that have a big appetite for axolotl eggs and larvae.

Still, some experts contend that efforts to ensure the species' survival appear to be paying off.

"It is growing in many labs around the world, and in aquariums," said anthropologist Roger Bartra. "While it is preserved artificially, it lives a more modern, cosmopolitan and transnational life."

(China Daily 09/12/2014 page10)