From the publication of his 1898 thesis (Animal Intelligence: An Experimental Study of the Associative Processes in Animals) onward, comparative psychologists
in the U.S.
Todd Freeberg of the University of Tennessee at Knoxville, who has studied chickadee communication, says that Templeton's work is "really starting to chip away at understanding the richness of the information" that chickadees can communicate.
"Conventional wisdom would say that [people] train dogs to do this," explains Michael Tomasello, a comparative psychologist
at the Max Planck Institute in Leipzig, Germany.
To ensure valid comparisons with human studies, the multidisciplinary team of ornithologists, primatologists, and comparative psychologists
applied methods that have been traditionally used to infer intentional communication and joint attention in pre-linguistic human children.