0.5% low chance for a baby mob to spawn as the old model

Something else for players to do and collect later on in the game. Also it won't break and change any of our zoo's, animal habitats and places, homes we built for the mobs already. 

I know the update is nearly out and this could be late notice but I think it's a good idea with this system the new spawns will be the new mobs other than a rare low percent.

I'm not sure how the game works behind the scenes if it even has a system for variant appearance spawns or if they would be seperate mobs, but this might mean they are still a mob spawnable in the game like how the zombie horse was in the game but just never spawned.

Hope this makes sense.