From the Division of Biological Sciences, University of Missouri:
It takes quick reflexes to catch small, colorful lizards called anoles. Manuel Leal has mastered the task, which involves lassoing the lizard with a dental floss noose suspended from a pole. The only quicker reaction may be that of the Division of Biological Sciences when it learned the evolutionary biologist might be persuaded to join the Mizzou community.
Leal has been studying anole lizard behavior for over two decades, with the objective of understanding the mechanisms that shape the evolution of behavioral and physiological traits, and their role in promoting species diversity. He spends a significant amount of time catching and researching lizards on the islands of the Bahamas, Jamaica, Hispaniola, and Puerto Rico, where hundreds of species of anole can be found. His studies have appeared in top scientific journals including Science, Nature, Proceedings of the National Academy of Sciences USA, Proceedings of the Royal Society of London B, The American Naturalist, as well as featured in the New York Times, The Economist, National Geographic, Der Spiegel (Germany), The Daily Mail and in a Canadian TV series “The Nature of Things” a well known series hosted by the inimitable David Suzuki and on NPR and CBC Radio.
So what was the lure of Missouri, where anoles can only be found in pet shops? Leal says he was attracted to the diversity of labs studying animal behavior and evolutionary ecology at MU. “We hope that our arrival here at Mizzou can broaden what is already an impressively broad research program in animal communication, which includes work on acoustic and vibratory signals and evolutionary ecology,” he says.
The faculty were also a huge draw for him. “My colleagues here take the same organismal approach to science that I do. They address really strong theoretical problems, but they keep in mind the natural history of the organism. It’s a group that fits well with how I enjoy doing science.”
Leal completed his doctoral studies at Washington University in St. Louis with world-renowned evolutionary biologist Jonathan B. Losos (now at Harvard). After his doctoral studies, he secured a National Science Foundation Postdoctoral Fellowship, which he conducted at Union College in New York. He then accepted his first faculty position at Vanderbilt University prior to being recruited to Duke University. In addition to his top-flight research credentials, Leal enjoys teaching courses on the evolution of animal behavior, herpetology, and sexual signaling. He officially joined MU’s faculty as an associate professor this past September.
So Many Species, So Little Time
One of Leal’s current projects focuses on the role of communication in reinforcing species boundaries in communities of anole lizards.
“Male anoles use a visual signal that consists of the display of a colorful throat fan, called a dewlap. Anole species that are found in sympatry — that is, are members of the same community — can be easily distinguished by the color or pattern of their dewlaps, which is unique to each of the species. This signal allows lizards to easily detect, recognize, and mate with members of their own species, and to avoid interbreeding and unnecessary competition with other similar species,” says Leal.
The questions he asks are, how do anoles detect and discriminate dewlap colors and patterns displayed by different species? And how do differences in habitat lighting affect these capabilities? His studies incorporate both lab and field research and span a variety of subjects, from physics and sensory physiology to cognition and computer modeling.
Leal is also interested in understanding the cognitive abilities of anoles as a possible behavioral driver of evolutionary change. In 2011, Leal captured worldwide attention when his lab showed that anoles exhibit problem-solving skills usually associated with mammals and birds. Leal found that anoles can solve novel problems, remember solutions, and “unlearn” incorrect approaches.
While many people are surprised to learn that lizards are brainier than we once thought, Leal’s response is, of course they are.
“The ability to learn or behave in a way that is advantageous should be very common,” says Leal. “It doesn’t make sense for a lizard to not be able to learn something new, because its environment is constantly changing. The alternative — that everyday they start from scratch — just makes very little sense.”
A “Boots on the Ground” Approach to Science
Results that make sense at the organismal level is important to Leal’s approach to science. His broad research program is characterized by developing an intimate understanding of his study organisms, knowledge that provides the basis for pursuing a hypothesis-driven line of research. He says he tries to teach this approach to his students.
“I tell my students that we are the boots on the ground,” Leal says. “Theoretical predictions need to be tested. In order to be tested, you need somebody that is willing to do the dirty work, somebody that wants to be working at the scale that really represents the organism and to ask, ‘okay, does this really matter?’”
A lot of Leal’s research involves documenting the behaviors of anoles in their natural environments. In practice, this means hours of filming anoles in the field, coupled with even more hours re-watching and transcribing these videos back in the lab. A fair amount of time is also spent catching anoles and collecting morphological data, such as dewlap color, body length, weight, as well as detailed documentation of many aspects of their habitat.
Leal says there are many reasons why anoles are a great system for studying evolution. There are hundreds of species, they have colonized a diversity of habitats, and they exhibit a wide range of complex behaviors. But the number one reason for him, he says, is because they are found in abundance in Puerto Rico — the place Leal calls home.
“They’re back home in Puerto Rico, and I can go back to the warm weather whenever I want,” says Leal.
Leal says he spent his Puerto Rican childhood catching all sorts of critters in the (forests or jungles), including anoles. His abilities paid off when one of his biology professors at the University of Puerto Rico, Richard Thomas, invited students to help him collect snakes with him.
“I said, I’ll go! That’s what I like to do. Then I started working with him and then I did my master’s with him,” recalls Leal.
Then, while working on his master’s degree, Leal met Jonathan B. Losos, who was so impressed with Leal’s lizard-catching abilities that he encouraged him to do his doctoral work in his lab.
“He promised me that as long as I was able to catch more lizards than him, then I would be successful at getting a Ph.D.,” laughs Leal. “The rest is history.”
Planting Seeds of Knowledge
His lizard-catching skills aside, Leal says he credits his scientific career to scientists, like Thomas and Losos, who encouraged him to pursue his interests. As the first person in his family to be lucky enough to have the opportunity to go to college, he says he didn’t really know much about academia.
“I had no idea you could make a living studying lizards. Even to this day, I often stop and think how amazing it is that someone pays me for being dirty and catching lizards. That’s cool,” he says.
Leal wants to inspire future biologists in the same way he was inspired. One way he does this is through an online blog —chipojolab.blogspot.com — where he posts regularly about his lab’s adventures in the field, their tinkering in the lab, and their latest research findings. (Chipojo is the common name given to large anoles in Cuba). Readers also are treated to plenty of stunning photographs and videos of lizards taken by Leal and his students, while also picking up a handful of Spanish words and phrases and insights into Puerto Rican culture. As his former professor once did, Leal also invites a couple undergraduates every year to join him in Puerto Rico and the Bahamas to collect data on lizard behavior.
At home and at his field sites, Leal frequently pays visits to elementary and middle school classrooms to talk to kids about lizards and about doing science; he also hosts the occasional high school student in his lab. Sharing his passion for science and for lizards with younger generations is only part of his goal.
“I want to open doors, like people did for me, and to show kids that if I can do it, then they can do it too,” says Leal.
Written by: Melody Kroll