Monique Reed schreef
There aren't a lot of ferns, cycads, etc. eaten today.

+ + +
Probably more than you'd think,
but it might be quite a bit of work to find out:
a) which ones
b) how plentiful they were, and when
c) what equally edible relatives they once had, and when

Nobody even mentioned the micro-organismic level

As this is a 'literary' effort it might be more important to draw up a
comparison to the other books using this device, so as not to duplicate
them.
PvR