The lizards that biologists just found thriving in the Hancock Park neighborhood of Los Angeles aren't a new species: they're the extremely well-studied green anole. But as the Los Angeles County Natural History Museum's Lila Higgins reports, the discovery marks the first confirmed established population of the common reptile in Los Angeles County, and scientists are curious as to what effect the little lizards may be having on native wildlife.

Green anoles are native to the southeastern U.S. and nearby islands, where --- ironically they're in trouble due to competition from exotic reptiles. Hancock Park isn't the first beachhead green anoles have made in the state: a population has been established in San Diego's Balboa Park for many years, and reptile watchers also report a thriving colony of the sleek lizards in and around Temecula. Individual green anoles have been documented in places like Northridge and Chino Hills.

And according to Higgins, Hancock Park neighbors have told Natural History Museum herpetologist Greg Pauly that the anoles have been there as long as they can remember.

It's been most baffling, given the amphibians' complex immune systems, not far off from the immune complexity of humans and other mammals.

"There's been a big question in terms of why the amphibian immune system hasn't been able to respond to this nasty skin infection," Louise Smith-Rollins, an associate professor of pathology, microbiology and immunology at Vanderbilt, tells Popular Science. "The question is, if it's a failure to recognize the pathogen, what's the defect?"

Rollins-Smith has been studying this immune response for more than 10 years, and she and her team have found another clue as to why amphibians can't clear this fungus. This week in Science, a paper she co-authored brings in new information to understanding the answer to that question. The study, led by Vanderbilt graduate students J. Scott Fites and Jeremy Ramsey, shows that it may be the second line of immune defense where the breakdown occurs.

The first line of defense, antimicrobial peptides produced in the skin, seemed to be effective at producing an immune response. But during the next stage, something happened to stop the usual inhibiting response.

"It appears that the defect is that the fungus itself is able to release factors that target vulnerable lymphocytes and induce them to commit suicide," Rollins-Smith says. "Mediators that should be regulating and calling in the troops, they're stopped right there."

It's been our experience that those who would spend two decades or more working closely with fishermen to understand and protect sea turtles typically have the best interests of both people and nature in mind, although sometimes they are called "turtle-huggers" or scapegoated over another competing agenda.

Back in the early 1990’s when we learned about the mass mortality of loggerhead sea turtles off the Pacific coast of Baja from geographers Serge Dedina and Emily Young, we responded immediately.

Here’s how Dr. Dedina describes what they found:



"We first started noticing the mortality of loggerheads on Magdalena Island on the trip out to Cabo San Lazaro in the Spring of 1994 when we noticed a few animals stranded on the beach. But as summer progressed we saw more and more. What was fascinating was to see the correlation between stranded loggerheads and the abundant coyote population who fed on the animals as they washed up. There were literally dozens of coyotes sitting in the dunes apparently satiated after a night of feeding.

By July 1994, on one return trip from San Lazaro, we counted more than 224 dead loggerheads, so many, that the fishermen we were with were clearly embarrassed. They all knew that the turtles were being caught in gill-nets. In fact we had been out shark fishing with fishermen in the spring and had seen the problem ourselves."