Scientists search for DNA of an endangered salamander in Mexico City’s canals

MEXICO CITY (AP) — Sixty years ago, residents of a canal-crossed borough in Mexico City could pluck axolotls — the large salamander reminiscent of a tiny dragon — out of the water with their hands because they were so plentiful. Now it’s almost impossible to find them in the wild.

That’s why scientists from Mexico’s National Autonomous University are filtering Xochimilco’s murky waters for traces of the endangered creature’s DNA .

“We all shed DNA along our path across the world and that can be captured by filtering air or water,” said biologist Luis Zambrano, from the university’s ecological restoration lab.

As they try to monitor the axolotls’ dwindling numbers, scientists increasingly rely on this technique as their nets come back empty during periodic surveys of the population, whic