Signs your aliens are a dodgy stereotype in disguise

As some of you may recall I helped run a panel on the use of "race" as a metaphor in sff at Swancon. Preparing for and doing that panel has made me really aware of just how often this is done, and done badly, and since I'm having a slowish day at work, I've been inspired to organise it all into two lists.

I talk about "aliens" here but it applies just as well to any other non human group. Similarly, I'm mainly thinking about race/ethnicity, but stuff like religion etc works too.

Anything in bold is in both lists and an automatic fail.
( Signs your aliens are probably humans in disguise )

( Things you just can't say about human groups )