If all the monsters in your Graveyard are Beast-Type: You can Tribute this card; Special Summon 1 Beast-Type monster from your hand or Graveyard, except "Uniflora, Mystical Beast of the Forest", but it cannot attack this turn.
Can special summon most beast monsters regardless of level or attribute.
Can special summon from the hand as well as the graveyard.
Has the requirement of only beast monsters in the graveyard in order to activate effect. If you have no monsters in the graveyard then you can't use the effect.
The special summoned monster can't attack the turn it's summoned.
Tips, related cards, skills
Uniflora can summon most beast monsters, but there aren't many strong beast monsters yet, making green and yellow baboon the only option for a good beast monster to special summon. If the condition to special summon the baboons is difficult for you due to lack of cards, you can use uniflora instead.