The past decade has seen a steady increase in studies oflemur behavior and ecology. As a result, there is much novel information on newly studied populations, and even newly discovered species, that has not yet been published or summarized. In fact, lemurs have not been the focus of an international symposium since the Prosimian Biology Conference in London in 1972. Moreover, research on lemurs has reached a new quality by addressing general issues in behavioral ecology and evolutionary biology. Although lemurs provide important comparative information on these topics, this aspect of research on lemurs has not been reviewed and compared with similar studies in other primate radiations. Thus, as did many in the field, we felt that the time was ripe to review and synthesize our knowledge of lemur behavioral ecology. Following an initiative by Gerry Doyle, we organized a symposium at the XIVth Congress of the International Primatological Society in Strasbourg, France, where 15 contributions summarized much new information on lemur social systems and their ecological basis. This volume provides a collection of the papers presented at the Strasbourg symposium (plus two reports from recently completed field projects). Each chapter was peer-reviewed, typically by one "lemurologist" and one other biologist. The first three chapters present novel information from the first long-term field studies of three enigmatic species. Sterling describes the social organization of Daubentonia madagascariensis, showing that aye-aye ranging patterns deviate from those of all other nocturnal primates.

Over the course of the past decade, there has been an enormous augmentation in the amount of information available on the lemurs of Madagascar. These advances are closely coupled with an increase in the number of national and international researchers working on these animals. As a result, Madagascar has emerged as one of the principal sites of primatological studies in the world. Furthermore, the conserva tion community has a massive interest in the preservation of the natural habitats of the island, and lemurs serve as one of the symbols of this cause. Between 10 and 14 August 1998, the XVIIth International Primatology Society (IPS) Congress was held in Antananarivo, Madagascar. For a country that about a decade ago was largely closed to foreign visitors, this Congress constituted a massive event for the Malagasy scientific community and was assisted by about 550 primatolo gists from 35 different countries. Naturally, given the venue and context of the Con gress, many of the presentations dealt with lemurs and covered a very wide breadth of subjects.

Over the course of the past decade, there has been an enormous augmentation in the amount of information available on the lemurs of Madagascar. These advances are closely coupled with an increase in the number of national and international researchers working on these animals. As a result, Madagascar has emerged as one of the principal sites of primatological studies in the world. Furthermore, the conserva tion community has a massive interest in the preservation of the natural habitats of the island, and lemurs serve as one of the symbols of this cause. Between 10 and 14 August 1998, the XVIIth International Primatology Society (IPS) Congress was held in Antananarivo, Madagascar. For a country that about a decade ago was largely closed to foreign visitors, this Congress constituted a massive event for the Malagasy scientific community and was assisted by about 550 primatolo gists from 35 different countries. Naturally, given the venue and context of the Con gress, many of the presentations dealt with lemurs and covered a very wide breadth of subjects."

The past decade has seen a steady increase in studies oflemur behavior and ecology. As a result, there is much novel information on newly studied populations, and even newly discovered species, that has not yet been published or summarized. In fact, lemurs have not been the focus of an international symposium since the Prosimian Biology Conference in London in 1972. Moreover, research on lemurs has reached a new quality by addressing general issues in behavioral ecology and evolutionary biology. Although lemurs provide important comparative information on these topics, this aspect of research on lemurs has not been reviewed and compared with similar studies in other primate radiations. Thus, as did many in the field, we felt that the time was ripe to review and synthesize our knowledge of lemur behavioral ecology. Following an initiative by Gerry Doyle, we organized a symposium at the XIVth Congress of the International Primatological Society in Strasbourg, France, where 15 contributions summarized much new information on lemur social systems and their ecological basis. This volume provides a collection of the papers presented at the Strasbourg symposium (plus two reports from recently completed field projects). Each chapter was peer-reviewed, typically by one "lemurologist" and one other biologist. The first three chapters present novel information from the first long-term field studies of three enigmatic species. Sterling describes the social organization of Daubentonia madagascariensis, showing that aye-aye ranging patterns deviate from those of all other nocturnal primates.