1. Is the inversion effect in rhesus monkeys face-specific?

   • L. A. Parr
   • J. T. Winslow
   • W. D. Hopkins

   Original Paper Pages: 123 - 129

2. How monkeys see the eyes: cotton-top tamarins’ reaction to changes in visual attention and action

   • L. R. Santos
   • M. D. Hauser

   Original Article Pages: 131 - 139

3. Structural analysis of tool-use by tufted capuchins (Cebus apella) and chimpanzees (Pan troglodytes)

   • G. C. Westergaard

   Original Article Pages: 141 - 145

4. Spontaneous logicomathematical constructions by chimpanzees (Pan troglodytes, P. paniscus)

   • P. Potì
   • J. Langer
   • K. E. Brakke

   Original article Pages: 147 - 156

5. Spontaneous class grouping behavior by bonobos (Pan paniscus) and common chimpanzees (P. troglodytes)

   • G. Spinozzi
   • F. Natale
   • K. E. Brakke

   Original article Pages: 157 - 170

6. The role of experience in web-building spiders (Araneidae)

   • A. M. Heiling
   • M. E. Herberstein

   Original article Pages: 171 - 177