Used to define and identify geological times.<span />
Labeo = gills
Dolphin= pisces
Tadpole = hibernation
snake= internal fertilization
Eagle = aerial mode of life
Human = mammals
A box full of feathers and the same size box full of rocks. They occupy the same volume but have a different mass.
(A 1 meter by 1 meter by 1 meter cube box full of feathers.
A 1 meter by 1 meter by 1 meter cube box full of rocks.)