Vol. 39 No. 1, January 1998

Haraway, Maury M.; Maples, Ernest G.: Flexibility in the Species-typical Songs of Gibbons..........1 Key Words: Gibbon; Reinforcement; Species-typical behavior; Variability; Vocal behavior.

Groves, Colin: Systematics of Tarsiers and Lorises..........13 Key Words: Loris; Tarsier; Taxonomy; Morphometrics; Cladistics.

Jablonski, Nina G.: The Response of Catarrhine Primates to Pleistocene Environmental Fluctuations in East Asia..........29 Key Words: Apes; Old World monkeys; Seasonarity; Life history parameters; Environmental change.

Zhang, Ya-ping; Ryder, Oliver A.: Mitochondrial Cytochrome b Gene Sequences of Old World Monkeys: With Special Reference on Evolution of Asian Colobines..........39 Key Words: Mitochondrial DNA; Cytochrome b gene; Old World monkeys; Phylogeny.

Perry, Susan: A Case Report of a Male Rank Reversal in a Group of Wild White-faced Capuchins ( Cebus capucinus )..........51 Key Words: Cebus capucinus ; Dominance; Aggression; Social strategies; Social intelligence.

Watts, David P.: A Preliminary Study of Selective Visual Attention in Female Mountain Gorillas ( Gorilla gorilla beringei )..........71 Key Words: Mountain gorillas; Attention; Visual monitoring; Social relationships.

Short Communications

Su, Bing; Wang, Wen; Zhang, Ya-ping: Protein Polymorphism and Genetic Divergence in Slow Loris ( Genus Nycticebus )..........79 Key Words: Genus Nycticebus ; Protain electrophoresis; Genetic diversity; Genetic divergence.

Koenig, Andreas: Visual Scanning by Common Marmosets ( Callithrix jacchus ): Functional Aspects and the Special Role of Adult Males..........85 Key Words: Callithrix jacchus ; Adult males; Visual scanning; Vigilance; Predators.

Laska, Matthias; Sanchez, Edith Carrera; Luna, Ernesto Rodriguez: Relative Taste Preferences for Food-associated Sugars in the Spider Monkey ( Ateles geoffroyi )..........91 Key Words: Taste preferences; Sugars; Relative sweetness; Spider monkey; Ateles geoffroyi.

Research Report

Rao, A. J.; Ramesh, V.; Ramachandra, S. G.; Krishnamurthy, H. N.; Ravindranath, N.; Moudgal, N. R.: Growth and Reproductive Parameters of Bonnet Monkey ( Macaca radiata )..........97 Key Words: Bonnet monkey; Reproduction; Endocrine physiology; Hormone.

Book Reviews..........109