Earth Science, Thursday Bell Ringer, 2.21.19

The standard method used to divide the Earth's long history into manageable parts

• relative age

• geologic time scale

• fossil record

• Permian extinction

Greatest mass extinction of all time - ended the Paleozoic era

• extinction

• Paleozoic era

• geologic time scale

• Permian extinction

Each rock layer is newer than the one below it

• law of superposition

• geologic time scale

• Permian extinction

• Paleozoic era

a fossil that is used to establish the age of a rock layer because the fossil is distinct, abundant, and widespread and the species that formed that fossil existed for only a short span of geologic time

• index fossil

• fossil record

• fossil

• relative age

The Death of every member of a species

• extinction

• Paleozoic era

• relative age

• Permian extinction

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

a historical sequence of life indicated by fossils found in layers of Earth's crust

• fossil

• geologic time scale

• species

• fossil record

Which is an example of absolute age?

• My baby brother is younger than I

• England is older than the USA

• Dinosaurs fossils are really old

• My dad is 42

Which is an example of relative age?

• My grandmother is 67

• The students are 12-13 years old

• I am younger than my mother

• My dog is 7

How old do scientists think the Earth is?

• 6.4 billion years old

• 6.4 million years old

• 4.6 billion years old

• 4.6 million years old