In their official 14 days of life, the chickens have grown 800%. They're huge!
They are probably not going to become enemies of Godzilla going from 1.25oz to 10.5oz, and we still move them from the poultry house, where they sleep, to their outside feeding space with a Rubbermaid container, so perhaps huge is relative.
They've also started chest-butting each other, flapping their wings while running, and scratching the ground for food with their feet -- in other words, they've begun to be chicken-y. Chest-butting, in particular, is a bit odd, like watching teenage boys celebrate a touchdown constantly for an hour.
Their wing feathers are coming in, and their combs are getting bigger. If you've ever wondered about that whole "birds evolved from the dinosaurs" theory, feel free to come over and check out their feet, because they are truly freaky.
Since moving in to the poultry house about 4 days ago, the ducks have been totally incredulous that all these weird peepy things have to sleep in the same space. In fact, they pretty much look askance at the chicks all day long.

