BIRD, COMMON NAME FOR ANY MEMBER OF CLASS VERTEBRATES THAT CONTAINS ANIMALS WITH FEATHERS. ALL ADULT BIRDS HAVE FEATHERS. ALTHOUGH SOME SPECIES LIKE PELICANS, KINGFISHERS,,ETC ARE COMPLETELY NAKED WHEN HATCHED
Mammals
MAMMAL, COMMON NAME APPLIED TO ANY WARM BLOODED ANIMAL BELONGING TO THE CLASS THAT INCLUDES HUMAN BEINGS AND ALL OTHER ANIMALS THAT NOURISH THEIR YOUNG ONES WITH MILK, ARE COVERED WITH VARYING AMOUNTS OF HAIR AND POSSESS A MUSCULAR DIAPHRAGM !!!
