animal Australia bear endangered grey koala mammal nature eucalypt eucalyptus gum leaves Marsupial arboreal arboreal herbivorous marsupial Australian cultural culture emblem emblematic eyes fauna features fur furry head herbivorous icon iconic image inactive koala bear national native nostalgia nostalgic phascolarctos cinereus popular pouched protected protection secure secured slow slow metabolism symbol symbolic wildlife background brown cute green leaf Planckendael sleep sleeping zoo cuddly marsupialTeddy beart aged image old style aussie bark essential food fragrance fragrant habitat home oil sveres texture tree