Claudia Dryfus interviews Carl Safina at the NYT:
Among things, that they are capable of anticipation. For instance, they show much excitement when I simply touch my car keys, which might well signal that they are going to some place interesting, like the beach. That proves that they have imagination and even memory.
Another thing — and this shouldn’t surprise — they can be quite emotional. Some years ago, I lived with someone with a dog. Before we broke up, we argued a lot. Once, we took her dog to the beach and we started bickering there. That dog just basically collapsed into a pile of leaves and would not get up. She did not want to be with us! And we weren’t even yelling at her. She just did not want to be a part of an unhappy scene.
That showed me that they can have a real-time valuation of their experiences. They know what they prefer to avoid.
more here.