it is a mod created by the known modder dr sharkz,it was created not to long ago and it is compatible with the newest alpha version,this mod,as it name suggests,adds a whole new ecosystem of fauna to the world of minecraft.
it is actually on version 2.0 and can be downoaded following the instructions here(it also requires the audio mod,link in the download page)
Friendly mobs
- horses,even though it can damage you,it will not attack you,they drop leather and can procreate (look at mob details)
- foxes,these wil not attack you,but they will atack small mobs such as birds
- birds,these have 4 diferent designs,each one with a diferent sound,they can be fed with seeds
Passive mobs
- bears,these will not attack the player unless it gets really near or harm the bear,it usually prefers hunting other mobs.
- boars,a replacement for pigs,these are brown and will atack the player if harmed,they deal around 2 hearts of damage.
- lions,these attack other mobs and players if they get closer than 7 squares.
Agressive mobs
- sharks,these where recently added,they will kill anything that falls on the water exept for squide,for breeding details check mob details
- male lions,these can be recognized by their mane,these will attack the player on sight,they are extremely dangerous
- polar bears,these will only spawn on snow and will attack the player on sight