This article from the Sioux City Journal is a must-read. It describes the work of Jason Kolbe, a graduate student who studies the brown anole (Anolis sagrei), a lizard native to the West Indies that is showing up in Florida, Hawaii and even Taiwan (.pdf file). Jason even spent a month in Cuba with fellow researchers, collecting skin samples or tails from lizards across the island. Using molecular tools, he can then compare the DNA of brown anoles from all over the world, to determine how the species has spread from one place to another. While brown anoles are not yet considered a problem in most areas where they have been introduced, they are thought to be outcompeting the native green anoles (Anolis carolinensis) in Florida. Bonus points to the Journal for using the lizard's scientific name.