The history of the development of Earth's nature
Answers are for parents and teachers.
1
List the three Phanerozoic eras from oldest to youngest and add one important event for each.
Paleozoic (ancient marine life, later land plants, coal forests), Mesozoic (dinosaurs), Cenozoic (mammals and the appearance of humans).
2
The Cenozoic lasted 66 million years and the Mesozoic 186 million. How many million years together? (Number only.)
252
3
Earth's history is 4600 million years. Divided into 46 equal parts, how many million years is each part? (Number only.)
100
4
Why do fossils help to determine the age of rocks? Write 3–4 sentences.
Each period had characteristic organisms whose remains are preserved in rocks. If the same fossil is found in rocks in two places, they are considered to have formed in the same period.
5
How might the breakup of Pangaea have affected nature? State two consequences.
Climate and ocean currents changed; animal and plant species became separated and developed independently in new areas.