What Will Aliens Look Like?

[MadImmortalMan]

Like this.

[JacobL]

???

[dps]

Wel

Inspired by the small Starship Troopers discussion and this.

The link is really pretty interesting for anyone with any interest in paleontology, as you'll instantly recognize a lot but there are some clever (and occasionally disgusting, like the second head/penis thing)differences. 

But I'm curious.  We have an amazing history here on earth of convergent evolution, but do you think this would apply to other, presumably reasonably similar planets?  Are we going to find streamlined animals in oceans with bodies like dolphins or tuna and ichthyosaurs, and large back-boned creatures on the shores? Or a bunch of blobs? 

Can we know anything?

Well, we only know of one world on which life exists.  It's pretty much impossible to extrapolate from one data point.

[Jaron]

[Strix]

Obviously balls of light!

If not than something harmless and cute that will suck our brains out or burrow inside our intestines.

[Grinning_Colossus]

Sentient ones will look like a machine intelligence. Aside from that, they'll likely have legs if they're terrestrial, fins if they're aquatic, etc., with sensory organs clustered around the nervous system hub.