My intended claim was that we should be more aware of the evidence presented. I also do believe that when we are aware of the available evidence, we will come to disregard most of the references we see to the the content and causes of human nature, but this will depend on how you weigh the evidence.
However, if it will make the matter clearer, I can give you an example of evidence-based claims in the field of anthropology.
Here's one that I hope isn't too politically charged, but is still interesting: According to the Ethnographic Atlas Codebook derived from George Peter Murdock’s Ethnographic Atlas (1981), which recorded the marital composition of 1231 societies, from 1960-1980, 186 societies were monogamous, 453 had occasional polygyny, 588 had more frequent polygyny, and seven had polyandry.
Claims that could be made based on this include:
Obviously, some of these claims you would not make unless you had a specific ax you wanted to grind. Some of these claims wouldn't be supported by the data. Some of these claims would depend on how you, personally, tend to weigh evidence (particularly the normative ones). Even the first claim, the one most supported by the evidence, is questionable if you disagree on the terms (e.g., what constitutes as a distinct culture?). But this is the sort of thing that we (by which I mean pretty much all of us) are used to dealing with in the soft sciences -- we know how to navigate these things. Unfortunately, people are much less willing to navigate fuzzy data accurately, and often much less motivated to navigate human data honestly.
One fallacy that I see frequently in works of popular science -- and also here on LessWrong -- is the belief that we have strong evidence of the way things were in pre-history, particularly when one is giving evidence that we can explain various aspects of our culture, psychology, or personal experience because we evolved in a certain way. Moreover, it is held implicit that because we have this 'strong evidence', it must be relevant to the topic at hand. While it is true that the environment did effect our evolution and thus the way we are today, evolution and anthropology of pre-historic societies is emphasized to a much greater extent than rational thought would indicate is appropriate.
As a matter of course, you should remember these points whenever you hear a claim about prehistory:
Results that you should have reasonable levels of confidence in should be framed in generalities, not absolutes. E.g., "The great majority of human cultures that we have observed have distinct and strong religious traditions", and not "humans evolved to have religion". It may be true that we have areas in our brain that evolved not only 'consistent with holding religion', but actually evolved 'specifically for the purpose of experiencing religion'... but it would be very hard to prove this second statement, and anyone who makes it should be highly suspect.
Perhaps more importantly, these statements are almost always a red herring. It may make you feel better that humans evolved to be violent, to fit in with the tribe, to eat meat, to be spiritual, to die at the age of thirty.... But rarely do we see these claims in a context where the stated purpose is to make you feel better. Instead they are couched in language indicating that they are making a normative statement -- that this is the way things in some way should be. (This is specifically the argumentum ad antiquitatem or appeal to tradition, and should not be confused with the historical fallacy, but it is certainly a fallacy).
It is fine to identify, for example, that your fear of flying has a evolutionary basis. However, it is foolish to therefore refuse to fly because it is unnatural, or to undertake gene therapy to correct the fear. Whether or not the explanation is valid, it is not meaningful.
Obviously, this doesn't mean that we shouldn't study evolution or the effects evolution has on behavior. However, any time you hear someone refer to this information in order to support any argument outside the fields of biology or anthropology, you should look carefully at why they are taking the time to distract you from the practical implications of the matter under discussion.