The opioid theory may help to
> explain why, once people are eating gluten-containing grains, it
> is hard for them to give them up.  It is not a plausible
> explanation of why they started gathering them in the first
> place, especially if the earliest grains gathered did not have
> gluten.

Todd, on this post I agree withyou 100%.  The first domestication would have
started with undigested grain seeds sprouting in the latrine dumps. Since
wandering over the fields paleo man would have selected bigger grains as
better to eat, this would have promoted some selective pressure.
Self-shattering seeds would have less opportunity to be eaten and hence get
to latrine dumps.

The more important question for us is how much grains should we eat and
which ones they should be.  Now that we know gluten erodes the gut wall, do
we still want to consume it?

Andrew