a fossil known to have lived in a particular geologic age that can be used to date the rock layer in which it is found
the remains (or an impression) of a plant or animal that existed in a past geological age and that has been excavated from the soil
someone whose style is out of fashion
a number or ratio (a value on a scale of measurement) derived from a series of observed facts; can reveal relative changes as a function of time
a numerical scale used to compare variables with one another or with some reference number
the finger next to the thumb
provide with an index
an alphabetical listing of names and topics along with page numbers where they are discussed
