Dr. Elizabeth Brannon has been conducting a study of numerical cognition in lemurs for several years now, and it involves the use of a touch screen computer. In a variety of trials that test numerical aptitude, the animals select from a series of photos on the computer screen and are rewarded for correct choices. Rather than bring the animals to the computer, the computer was installed in a mobile lemur-proof cart and it is wheeled into their cages for trials. You cannot imagine the glee in their little lemur eyes when the animals see that cart approaching. Not only are the lemurs happy, but this research has produced some fascinating results, showing that lemurs have transitive reasoning abilities, making it likely that the primate ancestor also had higher cognitive abilities than previously thought.
And let me tell you about Teres, a ring-tailed lemur whose female companion moved to another institution. He was depressed and losing weight. He then started participating in a project by Dr. Matthew O’Neill where oxygen consumption was measured as lemurs walked and ran on a treadmill to get an idea of how much energy was expended as they transitioned their gaits. Some lemurs -as some people- are much more inclined to walk on a treadmill than others. Some, in fact, just sit down and ride it to the back. Because this type of research at the DLC requires voluntary animal participation, the latter lemurs quickly earn a pass. Teres, however, took to the treadmill like a fish to water and not only provided an exceptional amount of data which allows us to better understand lemur energetics, he resumed his normal weight and is now living happily with another female, Cleomenis. It just goes to show that getting out, doing a little research, and getting some exercise can have a positive impact on your life. Even if you are a lemur.
We here at the DLC make every effort to come up with ways to make participation in research a form of animal enrichment; generally all it takes is a little creative thinking, positive animal interaction, and a handful of raisins.