I understand why scifi movies make aliens look so much like humans (even little green men), but in real life when I look at the diversity of life in our own planet (compare marine life with birds for instance), I can't help but think if there's life in other planets it may be so different from us that we may not even recognize it at first.

Think about it, even if on our own planet if evolution took just a tiny winy bit different path, we may not have had two eyes in the front giving us the ability to see in 3D. We may well have had infrared vision. We could rely on sensors, sensing change in heat / light etc instead of seeing how we do today. We could've had wheels or wings instead of feet (or could have 8 feet). We could be amphibions. Heck some other intelligent life well could have had exoskeleton and spoken a language that we (modern humans) couldn't even hear because we hear sound waves in such a small band!

So what if we do meet aliens but we cant hear their voice at all, let alone eventually learn to fluently speak each others' language. What if we can just sense their presence through indirect means, rather than directly seeing them?

I tend to think there's a higher probability that intelligenet life elsewhere in the universe would be extremely different from us. What do you think? Should sci-fi movies cut back on showing humanoid aliens?

I agree Greg Bear described some wierdo lifeforms in his book Space.

In most of the movies, the non-humanoid (intelligent) aliens mostly seem to be somehow evil, malignant, and bent on humanity's demise.

Given the number of rather outré body plans and life styles of some of the species on Earth, somebody should tell the writers about tolweb.org and other biological web sites.

Of course, SF writers have more freedom, as they don't have to contend with special effects budgets. I suspect the SF writers' community has more people who actually think about things like what extraterrestrials would look like and how they would behave than does the community of Hollywood script writers.

This is a bit of a recurring topic on many science related boards. Here's a recent local thread on the subject:
How strange is the life in space?

In astrobiology as well, the likely shape of an intelligent alien is of course one of the often speculated subjects... And in fact there are several scientists working on the related fields who have argued that a "Star Trek weird forehead alien" is just about as exotic and far removed from homo sapiens as they can come.

I'd like to think nature is a bit more inventive than that, but then I'm no biologist (let alone astrobiologist). And while I'm not a scriptwriter either, I should think they would like to write in some more exotic stuff as well... However, budgetary limitations tend to curtail their creativity. With the steady march of CGI technology, I suspect we'll see more weird forms in the future tho. Literary scifi after all has many examples thereof.

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