The team analyzed a small region of DNA from more than 600 different individuals to get a genetic "ID card" for each lizard. The historic home for Anolis sagrei is the Caribbean, especially Cuba, where the researchers have found that there are at least eight genetically distinct groups of the lizard. In the late 1800s, Anolis sagrei was introduced (probably through a shipment of goods) to the Florida Keys, got a toehold and, after a decades-long lag, began spreading into the Florida mainland in the 1940s, most likely from separate introductions.
Jason Kolbe, a doctoral candidate in biology at Washington University, gathered genetic samples of Anolis sagrei throughout Florida in 2003. Using a genetic database for Anolis sagrei developed in collaboration with fellow Washington University graduate student Richard Glor, he then analyzed the introduced samples in comparison to the Cuban ones, not only in Florida but also in Hawaii, Taiwan, Jamaica, Grenada and Grand Cayman.
The researchers were able to identify Florida as the source of new populations in the other countries by finding genetic variation shared by Florida and the other introduced populations. Genetic variants found in the newer locations more closely matched those of populations in Florida.
"The basic idea that drove this research was to determine where the newly introduced populations in Florida and elsewhere came from," said Kolbe. "We discovered that once an introduced species gets established in an area it can become a source for introductions elsewhere. And we also f
Contact: Tony Fitzpatrick
Washington University in St. Louis