Mammals

Mountain caribou

Mammals are warm-blooded vertebrates which nurse their young; that is, females secrete milk used to nourish infants. Indeed, the word, mammal is derived from the Latin word for breast, mamma.

Mammals also characteristically have fur (or hair) for insulation.

  hooves  from bighorn sheep to mountain caribou.

  carnivores  from bears to otters.

  rodents  from muskrats to squirrels.

  hares, pikas 

  bats 

  tracks  show what passed this way.