Migration For Various Mobs

Minecraft’s mobs all have biomes which they call home. However, some biomes don’t have much of a use in terms of mob spawning. I think that mobs could move from specific biomes (maybe every time the moon spins?) and spawn there. Starting with animals. In the real world, many animals migrate, but some don’t. I think that cows, sheep, pigs and chicken should spawn wherever, but when the migration period starts, they spawn more in Savanna’s and Plains. The other animals could do similar but with different biomes that make more sense. Some would not migrate, like the mooshroom. Silverfish could go deeper in caves when it’s not raining, but when it is they will go closer up. Humanoids should change a bit too. Villagers should have some distant village in a cold and a warm biome that they have a clear path too. I don’t know if they should actually take the path, but they can at least teleport to the other village. They will return later on. Undead mobs would spawn more near the villagers but also near ruins, where they stay.