Hi V,
I always hate evolutionary arguments. They mostly end up with someone in essence arguing that evolution is essentially guided whether they realise it or not. It's not guided. Mutation is random. And selection favours those genes / traits that allow a creature / species to survive and reproduce. If intelligence helps them do that, then it will be selected for. But very often it doesn't. Consider sharks. One of the most highly rated predators in the marine world. Evolution has not made them particularly smart. It's mostly sharpened their senses, streamlined them, added to their speed and stealth etc. In fact it's so advanced them that they haven't really evolved in hundreds of millions of years.
Humans didn't evolve intelligence to help them hunt. But rather to survive. So we need intelligence to use tools, act socially / form tribes, communicate etc.
If you're going to argue that intelligent aliens are aggressive because of evolution, you have to show why aggression is a beneficial trait to them. It may well be. It may also not be. There's no reason a herbivore can't be intelligent. Think of whales - filter feeding ones. Why are they so smart relatively speaking? It's only a question of why that intelligence helps it to survive and procreate.
The other problem that keeps cropping into these sorts of arguments is that people often confuse tech advancement with evolution. It's not. Evolution takes place over millions of years. Tech advancement has nothing to do with it. And quite frankly modern man is likely no more intelligent than man of fifty thousand years ago. Its been argued that Neanderthal's were smarter than cromags. It just didn't help them.
Cheers, Greg.
I can agree with some of your points.
Most certainly it is unlikely that our current intelligence differs much from that of Cromagnon. However evolution does sometimes take place much, much faster when either the species is under massive pressure or when there are significant vacancies in the ecology after, say, a major extinction event. Also evolution should be measured in generations not years, so very short lived species such as fruit flies can evolve very quickly. However that has little to do with my arguments.
I sincerely hope I never gave the impression evolution was guided. As you say it most certainly isn't other than the abstract guidance of survival. And yes if intelligence assists in that then intelligence will evolve. Regarding filter feeding Cetaceans, let me briefly put my pedant hat on as state that they are still predators! However I agree not a lot of intelligence is required to filter feed. Except maybe knowing where and when they will find the krill etc. Also I would say we really don't know just how intelligent the big filter feeders actually are! But they are physically very handicapped when it comes to manipulating their environment which is when I suspect the intelligence traits can really kick in big time, as in making tools etc.
I also don't think I ever stated that intelligence is inevitable for a predator just more likely. If the predator is already extremely successful, like your shark example, then it's unlikely small incremental increases in intelligence would provide any significant advantage. And that's the other thing about evolution, of course, not only is it slow but it moves in small incremental stages. So it's no use asking if an intelligent rabbit would stand a better chance against foxes, of course it would, but rather would a
minutely more intelligent rabbit have a better survival rate than a
minutely faster rabbit. My vote goes to the latter.
So I don't say that all predators will inevitably be intelligent (I doubt there's a
lot of intelligence in a snake), but I do think intelligence is a trait that is more advantageous to predators. I also would dispute your claim that humans evolved intelligence to use tools. Chimps are just hitting that stage but I would argue they have had higher than average animal intelligence for a long time. As for acting socially; I would ask why is social behaviour a successful trait? And I would argue that it is because it makes for more efficient food gathering (hunting in packs etc) and defense of your territory. It all comes down to ability to survive in the end.
Incidentally one of the reasons I think intelligence is likely to favour omnivores or at least more catholic eaters than say wolves is that most carnivores have pretty much only got one hunting strategy whereas an omnivore will develop many; they must discover which fruits are edible and which are poisonous, a strategy for hunting a monkey is not going to work for hunting termites etc.
Finally I think I wrote everything in probabilities. I didn't say an intelligent alien
would be an aggressive, predator just that I think it's much more
likely than a pacifist herbivore.
As you might have guessed I find this a fascinating topic!