Is it a man or a woman?

 Archaeology is particularly fascinating when dealing with societies that don't have good written records. Determining the phenotypical sex (not gender) of human remains can be a challenge.

Doing it off the pelvis? Not always accurate. Lots of women have "male" type pelvises and vice versa.

Doing it off the grave goods? In some cases we're working out what gender the grave goods indicate based off of...yup. It can get circular.

So more recently we've started using DNA. Now, this can only determine the person's genetic sex. A genetic woman found with male grave goods might be a woman who took on a male role, a trans man, or even a man with no Y chromosome, which can absolutely happen. The first case is typically assumed as most likely. We can't prove trans-ness with no record of the individual, but I do wish researchers would be more open to the possibility. A genetic man found with female grave goods might be a person with AIS.

DNA sexing has two major problems:

1. It's expensive.

2. DNA degrades, so you can't always get a clear read.

Enter proteomics. This means taking a small sample from a bone or a tooth and looking for proteins produced on the sex chromosomes. It's much cheaper.

We can now theoretically determine the genetic sex of every set of human remains we have. And, for example, let's say we are studying a society with very strict gender roles and we find one individual who's sex doesn't match their gender. Or two. A very small number. Particularly if the individuals concerned are buried with female grave goods (men pretending to be women to get ahead is historically rarer than the reverse).

We may actually be able to prove the obvious: Trans people have always existed.