|MadSci Network: Evolution|
You are basically asking whether we could improve intelligence in animals by providing selective advantage for this. The answer is undoubtedly yes, although to do this via selection and evolution would take a very long time. Consider that dogs were domesticated, it is thought, over a period of at least 10,000 years. During this process traits were selected for and against by the humans running this "experiment." The result is that we have domesticated dogs that are recognized as one species containing many breeds adapted to different things; hunting, guarding, herding, etc. So, this could be done, but would likely take several times 10,000 years to accomplish.
There do exist some potential shortcuts. Perhaps, for instance, we could employ genetic engineering to change, in the dog, genes that we find affect intelligence (however we might agree to measure it) in humans. By trial and error and informed guesswork (because we do not yet understand how intelligence is genetically determined), we might be able to engineer certain changes in intelligence this way. Whether this is ethical or not remains in question. For some speculative science fiction on this topic, see the "Uplift" novels by David Brin. In these books, the author takes the standpoint that it is moral to uplift a species. This is open for discussion.
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