1. Why are males bigger than females in pre-copula pairs of Gammarus pulex?

   • Jonathan Adams
   • Paul J. Greenwood

   OriginalPaper Pages: 239 - 241

2. Responses to sugars and their behavioural mechanisms in the starling (Sturnus vulgaris L.)

   • Werner Schuler

   OriginalPaper Pages: 243 - 251

3. The foraging ecology of hoverflies (Diptera, Syrphidae): circular movements on composite flowers

   • Francis S. Gilbert

   OriginalPaper Pages: 253 - 257

4. Vocal learning in White-crowned Sparrows: sensitive phase and song dialects

   • Michael A. Cunningham
   • Myron Charles Baker

   OriginalPaper Pages: 259 - 269

5. Extra-pair copulations in the Pied Flycatcher (Ficedula hypoleuca)

   • Mats Björklund
   • Björn Westman

   OriginalPaper Pages: 271 - 275

6. Responses of pikas (Ochotona princeps, Lagomorpha) to naturally occurring terrestrial predators

   • Barbara L. Ivins
   • Andrew T. Smith

   OriginalPaper Pages: 277 - 285

7. Echolocation, development, and vocal communication in the lesser bulldog bat, Noctilio albiventris

   • Patricia E. Brown
   • Timothy W. Brown
   • Alan D. Grinnell

   OriginalPaper Pages: 287 - 298

8. The mechanism of nestmate discrimination in social wasps (Polistes, Hymenoptera: Vespidae)

   • David W. Pfennig
   • George J. Gamboa
   • I. Deanna Ferguson

   OriginalPaper Pages: 299 - 305

9. The influence of the ambient sex ratio and intermale competition on the sexual behavior of the red-spotted newt, Notophthalmus viridescens (Amphibia: Urodela: Salamandridae)

   • Paul A. Verrell

   OriginalPaper Pages: 307 - 313