Geologic Time Scale

Question 1

How old is earth

Answer 1

4.6 billion years

Question 2

4 eras

Answer 2

Pre - Cambrian time
Paleozoic
Mesozoic
Cenozoic

Question 3

Precambrian period

Answer 3

Anaerobic bacteria evolved followed by photosynthetic Bacteria and eukaryotes
Life in sea at the end and there was a single celled life mass extinction and includes plants and animals

Question 4

Cambrian period in Paleozoic era

Answer 4

Development of marine

Question 5

Ordovician and Silurian periods in Paleozoic period

Answer 5

First land plants and other marine life appear such as octopi, squid, starfish, coral

Question 6

Devonian period in Paleozoic

Answer 6

Ferns adapted to drier areas, insects appear on land

Question 7

Carboniferous and Permian periods in Paleozoic

Answer 7

Reptiles evolve from amphibians, winged insects evolve

Question 8

Triassic period in Mesozoic

Answer 8

First dinosaurs involved, mammals first appeared about the size of a mouse

Question 9

Jurassic period in Mesozoic

Answer 9

Dinosaurs are dominant on land and first bird appears

Question 10

Cretaceous period in Mesozoic

Answer 10

Dinosaurs still dominate

Crocodiles and sea turtle present in water

Question 11

End of Mesozoic period

Answer 11

Mass extinction of all dinosaurs and half of all plants and animals

Question 12

Paleogene period in Cenozoic

Answer 12

Grasses evolve providing a source of food, marine mammals evolve,

Question 13

Neogene period in Cenozoic

Answer 13

Cooling temperatures an mountain ranges formed

Question 14

Quaternary period in Cenozoic

Answer 14

Ice age, fish and mammals thrive, mammoths were common

Question 15

Geologic time scale

Answer 15

A timeline of earths history divided into eras, eons, and periods
Geologic time is based on both relative and radiometric dating