In Tooth and Tail you’re only really in control of a single unit - the commander. Production is tied directly to farms, as is your base of operation. From there you can build little Warrens that periodically spawn squirrels (aka The Distillery Brothers) or ferrets strapped with mortar cannons (aka The 3-2-1 Brigade) or even construct defensive structures. Unit caps are determined by the number of Warrens you’ve built and will keep spawning new troops as long as you’ve got the food to back it up. The farmers, by the way, are all pigs.