THE RULE SET OF THE ZOOKEEPER SYSTEM Z1 IF ?x has hair THEN ?x is a mammal Z2 IF ?x gives milk THEN ?x is a mammal Z3 IF ?x has feathers THEN ?x is a bird Z4 IF ?x flies ?x lays eggs THEN ?x is a bird Z5 IF ?x is a mammal ?x eats meat THEN ?x is a carnivore Z6 IF ?x is a mammal ?x has pointed teeth ?x has claws ?x has forward-pointing eyes THEN ?x is a carnivore Z7 IF ?x is a mammal ?x has hoofs THEN ?x is an ungulate Z8 IF ?x is a mammal ?x chews cud THEN ?x is an ungulate Z9 IF ?x is a carnivore ?x has tawny color ?x has dark spots THEN ?x is a cheetah Z10 IF ?x is a carnivore ?x has tawny color ?x has black stripes THEN ?x is a tiger Z11 IF ?x is an ungulate ?x has long legs ?x has long neck ?x has tawny color ?x has dark spots THEN ?x is a giraffe Z12 IF ?x is an ungulate ?x has white color ?x has black stripes THEN ?x is a zebra Z13 IF ?x is a bird ?x does not fly ?x has long legs ?x has long neck ?x is black and white THEN ?x is an ostrich Z14 IF ?x is a bird ?x does not fly ?x swims ?x is black and white THEN ?x is a penguin Z15 IF ?x is a bird ?x is a good flyer THEN ?x is an albatross