from 405 million to 345 million years ago; preponderance of fishes and appearance of amphibians and ammonites

approximately the last 63 million years

approximately the last 63 million years

approximately the last 63 million years

a movement in Europe from about 1650 until 1800 that advocated the use of reason and individualism instead of tradition and established doctrine

a movement in Europe from about 1650 until 1800 that advocated the use of reason and individualism instead of tradition and established doctrine

a movement in Europe from about 1650 until 1800 that advocated the use of reason and individualism instead of tradition and established doctrine

from 230 million to 63 million years ago

from 230 million to 63 million years ago

from 230 million to 63 million years ago