A lot of buildings require certain resources in the cities working area before it can be built. Most of them make sense, but some of them have requirements are so strict that it is incredibly unlikely for it be to fulfilled unless you use a great farmer to create it. Some examples: Homing Pigeon Coop Requires Stone and Poultry in city vicinity Is there a reason why a Flock of poultry built by subdued ducks, turkey, etc dont count for the poultry requirement? Or better yet, why cant a subdued pigeon build this, it would make much more sense. Falconer is similiar, requiring poultry and grapes (wut). It also must be built by a subdued hawk,eagle, or haast eagle. Its effect is rather minimal for how difficult it is to build. Shaman invocation Hut (animal) These huts require bison,cow,deer,sheep, or some other animals to be in city vicinity. Shouldnt a herd built by one of the subdued animals count for this? Many of these animals are fairly rare, and dont even reveal when you get shamanism. Most of the time you cant build any of the special buildings for Druidism and Shamanism. Even if you find a resource later, you can only build the invocation hut for the city nearby, and if you want it in other cities it must be placed by a great farmer, requiring a large amount of effort. It would probably be too much to allow a single resource to enable these buildings in all your cities. But I dont think its unreasonable to allow herds of animals to satisfy the requirement. These animals must be subdued, and you cant multiply them (for some reason despite.... having animal husbandry + herds living in your city) to spread to your other cities. You must subdue more of the animals to get more herds (sometimes impossible if you dont have enough land left). Actually some buildings already do this. A good example are the animal trainers like "Llama trainer, Horse Trainer, Elephant Trainer". Having the animal in the city vicinity enables you to build them, but having a Herd of said animal also allows it. Having the resource in your civ isnt enough to build it. Yet, you cant build a Horse Farm with a herd of horses. Or a Oxen farm with a herd of cows. Its not very consistent and most of these buildings provide very minimal benefit, so it doesnt make sense. Also, resources in the civipedia dont tell you what they can make. So while I have this great farmer and can put down many resources, it is actually hard to tell what each resource allows me to build in the city. If you dont know ahead of the time (like Rice or some other resources allows you to build Farmers Market, a amazing building) you can miss out on important buildings.