The AP reports on a study in Current Biology that demonstrates that animals can plan ahead. The study include a story about a chimpanzee in a Swedish zoo who collects rocks and, when irritated at zoo visitors, throws them at the visitors. The chimpanzee featured in the study, Santino, also was observed breaking up stones that are too big to throw, into pieces that would work better for his planned task.
This account clearly demonstrates that animals (or at least primates) do not just react instinctively, but think, plan, and take careful action--just like we do.
It's been forty years since primatologist Jane Goodall first observed chimpanzees making, and using, tools. After her discovery, anthropologists had to re-examine the human/animal border, since tool making had always been one of the major lines of demarcation.
Now, with the latest observations, we have to move the line separating humans and animals yet again, because clearly, thoughtful planned behavior is no longer a human characteristic.
The more we find out about the capabilities of non-human animals, the more we will also need to begin re-evaluating our treatment of them. Because if we can no longer justify the extreme levels of exploitation and abuse that we inflict upon animals on the basis of their lack of rationality, we must eventually come up with an entirely different way of treating them.