From Roger S. H. Schulman:

Re: Ravens show things to partners, a rare ability, study finds (Nov. 29): I'm confused by the news that the crows' behavior of "showing things" to its fellow birds is rare, and usually utilized only by humans and their close cousins. Domesticated dogs do this on a regular basis. Any dog owner knows this. The dog will look at the toy, then at the human, then back at the toy. Even lead the human to the toy. Isn't that the same behavior?