Geologic Time Scale

According to paleontologists, how old is the Earth?

• 3.5 Billion Years Old

• 543 Million Years Old

• 57 Million Years Old

• 4.6 Billion Years Old

What Era were mammals first seen?

• Precambrian

• Paleozoic

• Mesozoic

• Cenozoic

Place the following units in order, from smallest to largest

• epoch, period, eon

• eon, epoch, period

• period, eon, epoch

• period, eon, epoch

The era that we are currently in is known as the -

• Cenozoic Era

• Mesozoic Era

• Precambrian Era

• Paleozoic Era

What is the primary reason that dinosaurs became extinct?

• Battle Royale

• Impact of an asteroid meteorite

• Global Flood

• Ice Age

Age of fish and amphibians

• extinction

• paleozoic era

• fossil record

• Precambrian era

Age of reptiles (dinosaurs) Scientists believe that it ended due to a meteorite hitting the Earth, causing a thick layer of dust/dirt cloud (causing an ice age) due to the sun not being able to reach Earth's surface

• Cenozoic Era

• Paleozoic Era

• Precambrian Time

• Mesozoic Era

geologic time intervals that eras are divided into.

• geologic time scale

• era

• period

• epoch

Identify the Era:
called the "Age of Mammals"

• Precambrian
• Paleozoic
• Mesozoic
• Cenozoic

During the Cambrian Explosion that began the Paleozoic Era, the many new forms of life that evolved ____

• lived on land
• were invertebrates that lived in the sea
• were vertebrates covered with fur or scales
• were single-celled