More than that animals have been shown to not only communicate sources of food but they have also been able to communicate future tense such as food will be available tomorrow at some certain location. This is quite a linguistic trick. The ability to communicate events displaced over time and/or space was once thought to be a distinctly human capability. Some species seem to have individual names for each other when they make sounds that are used only to communicate to a specific individual. We really do not know the extensiveness of animal communications. Again the difference between humans and other animals is simply one of degrees rather than a difference in kind. I recently read an account of a gorilla that upon learning one of the females with an infant was missing took the troop to a secluded place where they stayed for a few days while being much quieter than usual. He eventually returned with the infant and gave the infant to the biological sister to raise. This suggests he communicated to the troop to stay someplace specific, not to leave that area until he returned and to be quieter than normal. One can argue that this reaction to a missing mother and child was instinctive behavior but since it has not been seen at other times when a mother a child disappeared that seems a difficult argument to make. Michael calls Alex's documented behaviors an "endearing trick" but has no reason to label it as such. If he hasn't read the book about Dr. Pepperbergs work with Alex he might want to before he labels these behaviors "endearing tricks". I don't mean the book "Alex and Me" but rather "The Alex Studies" which chronicles Dr. Pepperberg's studies with Alex. Also try "Animal Cognition in Nature" which is a collection of studies in just what the title says, animal cognition. The whole idea of instinctive responses to stimuli only or conditioned responses to specific stimuli being the only way animals are capable of communicating is rapidly coming apart. It is a ridiculous idea anyway but perhaps hubris is the only thing humans are capable of that animals are not. :)
John Thornton