In Mexico, the volcano axolotl, a species of amphibian salamander, is in critical danger of extinction as rivers where they develop are drying out. An environmental group has launched a fundraising effort to save them. In Mexico, the volcano axolotl, a species of amphibian salamander, is in critical danger of extinction as rivers where they develop are drying out. An environmental group has launched a fundraising effort to save them. NBC News Science