Anyone know anything about raising pastured chickens, ducks and geese?

Virtually all the information out there is the same and insists that poultry needs grain.
I'm a bit skeptical, although I'm not a farmer or an animal physiologist. I'm curious if
the notion that poultry need grain is based on the assumption that you want to reach
specific growth rates.

In nature, I can't imagine that foul would get much grain. Grass and insects would be the
two most common food sources. In the wild, plant seeds (grain) is only available for about 1/4 of the year--if that.

I imagine you could raise foul on pasture with no supplemental feeding, but the growth rate would
definitely be slower. There would also have to be enough insect life to meet their protein requirements.
Joel Salatin uses fly larvae in cow pats as protein source so an integrated operation would be better
than a monocrop of just chickens let's say.

The other issue is genetics. All the chicks you'd buy at a hatchery are breed to gain on grain. A farmer I
buy from had to import beefs from NZ just to get genetics that would do well on grass.

What's this groups POV on Cordain's paleo diet work?

I searched for  "Cordain" and got zero hits, which seemed odd.

I've been lurking for some time and decided to join.

I live in Ontario Canada near Toronto.

I've been influenced by the following books:

Nutrition and Physical Degeneration
The Fat of the Land
The Omnivore's Dilemma
Good Calorie, Bad Calorie
Manufacture of Consent
Guns, Germs and Steel

I am a philosopher by training so I tend to be pretty analytical and deconstructionist.

I recently stumbled upon the radio series "How to Think About Science" on CBC.
(http://www.cbc.ca/ideas/features/science/index.html)
I highly recommend it. It's a little technical but is still very accessible.

Lately I find myself become more and more critical of all the "science" I see paraded around
in the popular press. As Taubes details in GCBC, there is very little science going on in the
fields of weight loss, nutrition, and chronic disease. If you haven't read GCBC, it's a must read.

The other book which really explains the overall process at work is "Manufacture of Consent".
Most academic and scientific disciplines are very poorly grounded in hard science. Instead, they
abuse their power as monopolists over certain areas of knowledge to basically do as they please.
Usually this means making lots of money. But it also allows them to institutionalize their own pet
theories and personal bias essentially free of the bounds of reality. Taubes does an excellent job
detailing all this. As Chomsky points out, "truth" has very little to do with the consent or the reality
that various groups with power are able to create.