"While testing the biome code, I started running out of food in the game and started hunting animals. Cows would just stand there, looking at me as I mashed them over and over to get their precious loot, so I figured I’d just make that mechanic a bit more fun. Four lines of code later, and animals now flee randomly after taking damage. Hunting animals suddenly became a lot more fun and morally questionable as pigs would storm off grunting and chicken (or whatever the heck they are) would jump into ravines. But the real fun came later on."
I like how Notch doesn't even know what they are. I still say they look luck ducks. I wasn't too excited about the adventure update, to me it was just another update. This week has changed that drastically and I can't wait to get my pick into ver. 1.8.