The extent to which humans and nonhumans share numerical competency is a matter of
debate. Some researchers argue that nonhumans, lacking human language, possess only a …

Deciphering nonhuman communication–particularly nonhuman vocal communication–has
been a longstanding human quest. We are, for example, fascinated by the songs of birds …

This paper presents results of almost 30 years of study of the cognitive and communicative
activities of Grey parrots (Psittacus erithacus), conventionally regarded as mindless mimics …

A Grey parrot (Psittacus erithacus) had previously been taught to use English count words
(“one” through “sih”[six]) to label sets of one to six individual items (Pepperberg, 1994). He …

Abstract A Grey parrot, Griffin (Psittacus erithacus), previously taught English labels for
various colors and shapes with respect to three-dimensional (3D) stimuli, was tested on his …

Do humans and nonhumans share the ability to form abstract concepts? Until the 1960s,
many researchers questioned whether avian subjects could form categorical constructs …

This article attempts to investigate how much of phonology can be explained by properties of
general cognition and the Sensorimotor system—in other words, third-factor principles, in …

After re-reading essay “The Comparative Psychology of Intelligence” with all the associated
commentaries, I was struck by how contemporary many of the arguments and counter …

Images of Grey parrot skeletal anatomy and its vascular system are available at www.
avianstudios. com/the-grey-parrot-anatomy-project/images/(Scott Echols, DVM). Particularly …

Many studies on the evolution of communication devolve into treatises on human language
evolution, focusing on primates. If, however, we truly wish to develop models about …