This chapter is a brief summary of extensive published data. For more information and additional data on lemurs and other prosimians, consult Harcourt and others (1998); IUCN (1990); Segal (1989); Bennett and others (1995); and UFAW (1987).

The suborder Prosimii might constitute the most diversified set of living mammals. One major group, collectively referred to as lemurs, occurs in nature only in the Malagasy Islands. Its major taxonomic subgroups are the true lemurs (Lemuriidae), mouse and dwarf lemurs (Cheirogaleidae), indris and sifakas (Indridae), and perhaps the phylogenetically oddest of all primates, the aye-aye (Daubentonidae). Few are maintained in captivity; the most likely representatives to be seen in captivity are the Lemuriidae: the ring-tailed lemur (Lemur catta), the brown lemur (Eulemur fulvus), and the ruffed lemur (Varecia variegatus).

A second major group (Lorisidae) consists of lorises and galagos. All galagos in nature are from Africa; two members of the loris group are from Africa and two from Asia. Galagos are sometimes referred to as bushbabies, but this common name is sometimes applied to other animals as well. The thick-tailed galago (Galago crassicaudatus) and dwarf galago (G. senegalensis) are the only members of this group seen more than rarely in captivity.

A third major group consists of the tarsiers (Tarsius), from the islands of southeast Asia. The taxonomic position of tarsiers remains controversial; these animals are difficult to maintain in captivity, and few institutions attempt to do so.

Prosimii vary widely in size, dietary preferences, locomotor adaptations, social organization, and intelligence. Living prosimians range in size from the mouse lemur, with a body length of about 12 cm (5 in) and a weight less than 100 g (4 oz), to the tailless indri, with a body length of about 90 cm (3 ft). Different dietary adaptations in various genera and species are reflected in major differences in the alimentary tract. Differences in locomotor styles are reflected in major anatomical differences. All those contribute to the observed diversity in behavior and social organization. As body size and locomotor habits vary widely,

Front Matter (R1-R14)

Executive Summary (1-4)

Introduction (5-9)

1. Principles of Psychological Well-Being of Nonhuman Primates (10-14)

2. Essentials of a Program to Provide Psychological Well-Being (15-30)

3. General Care and Psychological Well-Being (31-46)

4. Effect of Special Research Conditions on Psychological Well-Being (47-54)

5. Prosimians (55-67)

6. New World Monkeys: Callitrichids (68-79)

7. New World Monkeys: Cebids (80-89)

8. Old World Monkeys: Cercopithecids (90-102)

9. Apes: Hominoids (103-112)

10. Research Needs (113-122)

References (123-142)

Appendix A Samples of Nonhuman-Primate Environmental-Enhancement Plans (143-155)

Appendix B Examples of Infectious Diseases That Preclude the Safe Housing of Mixed Genera of Nonhuman Primates (156-157)

Appendix C Biographical Sketches of Authoring Committee (158-160)

Index (161-168)