Arguments of human uniqueness emphasize our complex sociality, unusual cognitive capacities, and language skills, but the timing of the origin of these abilities and their evolutionary causes remain unsolved. Unlike the largely solitary ancestral mammals, the first primates are thought to have maintained social networks, communicating via vocalizations and scent marks. These networks may have facilitated selection for increased cognitive and communicative abilities at the very emergence of the primate order by providing a medium for kin selection (selection caused by behavior benefiting kin). Unfortunately, the mechanisms by which ancestral primates might have recognized kin are unknown. This study will be the first test of vocal recognition of kin in a species used to model ancestral primates, the grey mouse lemur. Innovative, sophisticated methodology includes marking wild lemurs with transponders and conducting playback experiments at feeding platforms containing transponder readers.
With respect to intellectual merit, this project is multidisciplinary, encompassing socioecology, anthropology, bioacoustics, conservation, and field methodology. The project will have great theoretical value for reconstructions of primate origins and will investigate the feasibility of developing novel conservation tools using vocalizations to monitor kin groups of small, nocturnal mammals.
The broader impacts are in conservation, education and international collaboration. These lemurs are vulnerable, not only because forest degradation in Madagascar is estimated to have exceeded 90% since the arrival of humans, but also because they are not well understood. Increased knowledge of their social systems will help tailor conservation plans to their needs. The co-PI will integrate this project into science education by creating a webpage so her NSF GK-12 students can follow the research as it progresses. The project will develop new collaborations between German, Malagasy, and American researchers. It will train a field assistant and a Malagasy student in skills vital for launching careers in research, conservation, or park management.
Humans have amazingly complex social systems, unusual cognitive capacities, and unique language skills, but the origins of these abilities are not well understood. This project reconstructs the social systems of ancestral primates, helping us understand how those origins may have set the stage for the subsequent human lineage to evolve into the extraordinarily social species we have become. Genetic, fossil and theoretical evidence suggests that the most common ancestor of primates had a small body size and small brain, was nocturnal, and foraged, most likely solitarily, for fruit and insects. Because mouse lemurs today are similar, we use them as a model for ancestral primates, and test whether they can recognize their kin via vocalizations. Data analysis is still in progress, but, if they can, it will suggest that a similar ancestral primate would probably have had the same cognitive and communicative abilities. This is exciting, because it means that such vocal communication could have been a crucial part of the foundation from which more complex forms of kin-based social systems evolved in primates. Data was collected during 2010 and 2011 in Ankarafantsika National Park, Madagascar on wild grey mouse lemurs and data analysis is still ongoing. The data collected will not only answer this question, but also contribute to the long-term monitoring and conservation of the mouse lemur populations in the park. The broader impacts of this project include international collaborations with the University of Veterinary Medicine Hannover in Germany and the University of Mahajanga in Madagascar. In addition to funding the Co-PI’s PhD research, this project also enabled a Malagasy Master’s student to collect, analyze, and write up data for her Master’s thesis and provided an undergraduate student with research experience that will lead to her Bachelor’s thesis. The Co-PI is committed to mentoring and improving science education for younger students, and during 2010, she collaborated with Lowell Elementary School in Phoenix, Arizona, to integrate her research into the fifth and sixth grade science curriculum. This involved creating an interactive website where the students could follow the research as it progressed and communicating with the students directly via SKYPE calls from Madagascar. As data analysis progresses, the findings will also be disseminated at scientific meetings and through publications in scientific journals.
