ESS - Earth's History

How long ago was the universe created?

13.7 billion years ago

What is the birth of the universe called?

The Big Bang

When did our Sun begin to form?

5 billion years ago

When was our solar system created?

4.6 billion years ago

How do scientists understand Earth's early atmosphere?

They look to Mars and Venus

Early Earth was:

hot

Earth's composition (6 elements):

Iron, Oxygen, Silicon, Magnesium, Nickel, Sulfer

The Earth's core is made up of:

Iron and Nickel

The solid inner core is how hot?

5,000-7,000 degrees Celcius

The liquid inner core is how hot?

4,400-6,000 degrees Celcisum

What is the thickest layer of the Earth?

the mantle

The mantle is ___% of Earth's volume

70

The mantle is made up of:

magnesium, aluminium, iron, and silica

This is the upper portion of the mantle:

asthenosphere

This is the rigid rock layer above the asthenosphere:

lithosphere

How did the first atmosphere develop?

release of gases by volcanoes

These formed when the continents started to drift apart:

oceans

Oceanic crust is made up of what?

molten material

These organisms are responsible for the oxygenation of Early Earth.

cyanobacteria

These are the remains or traces of past life forms:

fossils

What can the fossil record tell us?

How life looked like in the past

Some fossils of the same species can be found on the ___ coast of ____ ______ and the _____ coast of _______. This supports the idea that there used to be a _______.

east, South, America, west, Africa, supercontinent

What are the two types of fossils?

body and trace fossils

Animals appeared on the fossil record __________.

600 mya

This period was a rapid period of evolution. It was 542 mya and resulted in most major animal groups that exist today.

cambrian period

How many mass extinctions have scientists identified?

5

In order to be a mass extinction, __% of all species must be lost.

75

When new species fill ecological niches after a mass extinction, this is called:

adaptive radiation

fossils or organisms that share traits between an ancestor and a descendant:

transitional species

geologists divide Earth's history into sections based on what?

important events in geologic time

divisions of geologic time from longest to shortest:

eon, era, period, epoch

The first 3 eons are part of this time, and it is 90% of Earth's history:

Precambrian time

This is the most recent eon, and has the cambrian explosion:

Phanerozic eon

This mass extinction occured at the end of the Permian period, and wiped out 90% of all species on Earth:

The Great Dying

This era involves Pangaea, dinosaurs, and the mass extinction that wiped out the dinosaurs:

Mesozoic Era

This period was the time of recovery after the Permo-Triassic extinction:

Triassic Period

This period involved evolution of dinosaurs, and first birds:

Jurassic Period

This period ended with an asteroid that killed off the dinsaurs:

Cretaceous Period

This period is the most recent, involves the ice age, and is called the "Age of the Humans":

Quaternary Period

What are the 5 mass extinctions?

Ordovician, Devonian, Permian, Triassic, Cretaceous