How would cooperative and foraging chain work?
As clarified in the Climate rules, and as the system does it in the digital version, the food distributed would be 2 - 2 - 1.
-Creature A gets one food from long neck, it gets an additional from foraging.  Because it ate, the species to the right gets one plant food.
-Creature B gets one food and then an additional food from foraging. Because it ate, the species to the right gets one plant food.
-Creature C gets one food.  If it also had foraging it would get an additional food.

The designer (Dominic Crapuchettes) also clarified it in this thread here:  https://boardgamegeek.com/thread/1419292/foraging-cooperation-and-order-eating  

They also plan to post an official FAQ after the digital version is released.