proterozoic

adjectives

formed in the later of two divisions of the Precambrian era
"proterozoic life forms"
is derived from
is similar to
at or near the beginning of a period of time or course of events or before the usual or expected time
"early morning"; "an early warning"; "early diagnosis"; "an early death"; "took early retirement"; "an early spring"; "early varieties of peas and tomatoes mature before most standard varieties"
domain category
a science that deals with the history of the earth as recorded in rocks