According to an article by Marc Bekoff on the psychologytoday.com Web site, birds can plan future meals, fish remember and turtles grieve.
We all know that dogs produce a wonderful array of vocalizations. And now we know that dogs mean it when they [sic] "This bone is mine." Researchers from the Department of Ethology at Eotvos University in Budapest, Hungary, showed that when a dog has a bone and growls other dogs avoid him — the growl means "hands off my bone." They also discovered that a growl in play, for example, had a different acoustic structure and did not deter a dog from approaching the growler. The results show that aggressive vocalizations in dogs are context-specific and have a specific meaning when used to keep a bone from others.
Bekoff said we are learning more about the intelligence of other animals, including whether they can be emotional and have morals.
We need to keep an open mind on just how fascinating they are and how similar they are to us in many different ways. And, while there are many and significant differences, it's essential that we mind the similarities when we subject them to unnecessary pain, suffering, and death. We can all definitely do better in our interactions with other beings.