The missing lemur link. An ancestral step in the evolution of human behaviour.

Theoretical discussion and debate are open on which part of social behavior is really exclusive of Homo sapiens and other apes, and what, instead, is rooted in the common ground of primate origins. By the time of our common ancestors, lemurs have been following their own evolutionary pathway to become “modern primates”. This process, enhanced by Madagascar’s isolation from the rest of the world, which started about 80 millions of years ago, has led lemurs to possess a puzzling combination of features. In fact, they retain ancestral traits such as a small brain and communication highly based on smell combined with biological peculiarities, such as female dominance, lack of sexual dimorphism, and strict seasonal breeding. On the other hand, group-living lemurs share basic features with social monkeys and apes such as cohesive multi-male-multi-female societies, female philopatry, and individual recognition. Belonging to the most ancestral primate group, lemurs are the ideal model to shed light onto the ‘primate behavioral potential’ in terms of conflict management, communication strategies and society building and on how much these crucial aspects of social living are similar or different from those found in monkeys, apes and humans. Part of the perceived gap between strepsirrhines and haplorrhines probably lies in the divergent research methodologies applied to these two groups. The aim of this book is to review, and expand upon the newest fields of research in lemur biology, including recent analytical approaches that, so far, have been restricted to haplorrhines.