The Lizard’s Tale is a series of seven short films about Anolis lizard biology, produced by Day’s Edge Productions. Producers Neil Losin and Nate Dappen (lizard biologists before they switched careers to become filmmakers) worked with researchers to capture anole diversity, behavior, and science in Florida, the Bahamas, Puerto Rico, the Dominican Republic, and Costa Rica. Along the way, they produced the seven episodes of The Lizard’s Tale plus other short films for HHMI BioInteractive and bioGraphic, and ultimately created the first-ever primetime broadcast documentary all about anoles: Laws of the Lizard on the Smithsonian Channel (trailer below). The Lizard’s Tale and the accompanying videos and TV program were produced with funding from the Templeton Foundation, Howard Hughes Medical Institute, California Academy of Sciences, and Smithsonian Channel.
Anoles are lizards with an evolutionary story to tell. There are over 400 species of anoles, living all over the American and Caribbean tropics: from remote rainforests in the Greater Antilles to bustling mainland cities. In the last 50 years, anoles have become a “model organism” for studying evolution, ecology, and animal behavior. Scientists around the world have published thousands of studies on these humble lizards! Watch to find out what makes an anole an anole, and why these unassuming lizards have drawn so much attention from scientists.
The “Greater Antilles” – Cuba, Hispaniola, Jamaica and Puerto Rico – are hotspots of anole diversity. But what’s most surprising are the unexpected parallels between anoles living on different islands. Why do the anoles of Puerto Rico, with adaptations to various habitats, have a virtually identical set of lizard doppelgangers on Hispaniola? Did the lizards become specialized first, then spread from island to island? Or did they diversity in the same way several times? Testing the anoles’ physical performance and examining their DNA points to a surprising answer!
One way to understand the present day diversity of anoles, is to look back into their 60-million-year history. To do that, scientists rely on a number of techniques, from fossil hunting to DNA analysis. By reconstructing the evolutionary history of anoles, we can begin to understand how they spread in the Caribbean and the American tropics, adapted to every environment, and diversified into hundreds of modern species.
“Speciation” is the process by which one species becomes two. Many scientists define species as groups of organisms that cannot interbreed with one another. So what prevents anole species from interbreeding, and how do these “reproductive barriers” arise? One distinctive feature of anoles, the dewlap, seems to be a sort of species ID badge. And a massive new experiment may show us how natural selection can accelerate the speciation process.
Why do anole researchers favor tiny Caribbean islands for their work? Sure, they’re beautiful. But tiny islands are also relatively simple ecosystems, giving scientists a clear window into how ecological processes really work. Tiny islands in the Bahamas provide a rare opportunity to observe ecology and evolution in action, at a scale that researchers can manipulate and study. And the discoveries from these studies are changing how we think about the speed of natural selection.
Experiments on small islands show us that the presence or absence of one species can have huge effects on an ecosystem. Now, anole researchers are building on that knowledge to discover how the interactions between species have evolutionary consequences. When you add a new species into an ecosystem, how do the other species respond? And over several generations, how can their responses influence their evolution?
Some anoles are just as at home in big cities as they are in tropical forests. Understanding why may help us predict the effects of urbanization on wild animals around the world. Facing a new set of challenges – from slippery man-made surfaces to super-hot temperatures – how are anoles evolving to survive (and thrive!) in a human-dominated world? And why are some species better at coping with humans than others? New studies are revealing how some anoles are rising to their biggest evolutionary challenge yet.