The Complete History of the Earth: Archean Eon

Summary

In this video, we continue exploring Earth's history, focusing on the Archean Eon, a period of intense asteroid impacts and volcanic activity. This era saw the emergence of Earth's first large landmass and the earliest life forms, cyanobacteria, which played a crucial role in shaping the atmosphere by producing oxygen through photosynthesis. These organisms helped lower global temperatures and triggered the planet's first glaciation. The video concludes with the Earth's climate evolving and supercontinents forming as cyanobacteria colonies spread across the planet, marking a transformative chapter in Earth's history.

Takeaways

• 🌍 The Archean Eon began around 4 billion years ago, marking a significant period in Earth's history.
• 💥 The Late Heavy Bombardment occurred between 4.1 to 3.8 billion years ago, increasing the frequency of asteroid and comet impacts on Earth.
• 🚀 Comets contributed to Earth's water, with a large percentage of our current water believed to have arrived via these cosmic snowballs.
• 🌿 The first evidence of life on Earth, cyanobacteria, appeared around 3.6 billion years ago, playing a crucial role in shaping the planet's future.
• 🌱 Cyanobacteria thrived in the carbon dioxide-rich atmosphere and were Earth's first rulers, paving the way for all living plants.
• 🌋 Plate tectonics began around 3.2 billion years ago due to the cooling of the Earth's crust and active volcanism.
• 🌡️ The global temperature dropped significantly, but still remained high, averaging around 50°C to 85°C.
• 🌎 The first supercontinent, called Vaalbara, formed during the Paleoarchean era, consisting of parts of Western Australia and South Africa.
• ❄️ The first glaciation occurred around 2.9 billion years ago, due to the reduction of CO2 levels as a result of cyanobacteria activity.
• 🌿 The Neoarchean era saw the diversification of cyanobacteria, which evolved into new niches and covered different environments.

Q & A

What is the Archean Eon and when did it begin?

The Archean Eon is a period in Earth's history that began around 4 billion years ago. It is marked by significant geological and biological changes, including the formation of the Earth's crust and the emergence of early life forms.

What was the Earth like during the early Archean Eon?

During the early Archean Eon, Earth was characterized by a toxic atmosphere, frequent impacts from asteroids and comets, and a surface dominated by lava flows. It was not a hospitable environment by today's standards.

What is the Late Heavy Bombardment and when did it occur?

The Late Heavy Bombardment was a period of increased asteroid and comet impacts on Earth, occurring between 4.1 to 3.8 billion years ago. It is believed to have contributed to the delivery of a significant amount of water to Earth in the form of ice from comets.

How did the Late Heavy Bombardment affect the development of life on Earth?

The Late Heavy Bombardment may have had long-term effects that led to Earth becoming more conducive to life. The impacts brought water to Earth, which is essential for life as we know it, and possibly contributed to the formation of the Moon, which influences Earth's stability and climate.

What was the Paleoarchean era known for?

The Paleoarchean era, which lasted around 400 million years, was defined by the formation of the first large landmass, called Valara, and the earliest evidence of life on Earth in the form of single-celled organisms known as cyanobacteria.

What role did cyanobacteria play in the Archean Eon?

Cyanobacteria, also known as blue-green algae, played a crucial role in the Archean Eon by performing photosynthesis. They converted carbon dioxide into oxygen, which led to a significant drop in global temperatures and the first glaciation at the poles.

How did the climate change during the Archean Eon?

The climate during the Archean Eon transitioned from a hot, greenhouse state with high levels of methane and carbon dioxide to a cooler state due to the oxygenation of the atmosphere by cyanobacteria. This eventually led to the first ice age around 2.9 billion years ago.

What is the Neoarchean era and what happened during this time?

The Neoarchean era is the fourth and final era of the Archean Eon. It is characterized by the continued evolution and diversification of cyanobacteria, which spread across the globe, adapting to various environments and even colonizing dry land.

What is the significance of the supercontinent called Kenorland?

Kenorland was the first supercontinent during the Archean Eon, formed by the amalgamation of land masses. It was largely covered by microbial mats, which contributed to the oxygenation of the atmosphere and the transformation of Earth's surface.

How does the existence of stromatolites in Shark Bay, Australia, relate to the Archean Eon?

Stromatolites in Shark Bay, Australia, are modern-day equivalents of the ancient cyanobacterial mats that thrived during the Archean Eon. They provide a glimpse into the early life forms that dominated Earth's surface and played a key role in shaping the planet's atmosphere.

What is the humorous plea for subscribers at the end of the script about?

The plea for subscribers is a humorous way for the video creator to encourage viewers to support the channel. It ties into the theme of evolution by suggesting that reaching certain subscriber milestones might help the creator 'evolve' from a metaphorical state of being part of a microbial colony.

Outlines

00:00

🌏 Early Earth's Struggles

The script begins by describing the harsh conditions of early Earth, including a toxic atmosphere and frequent impacts from asteroids and comets. It outlines the beginning of the Archean Eon, a period three times longer than the one covered in the previous video. The narrator discusses the increasing geological record as we approach the present day and the division of the Eon into eras. The Late Heavy Bombardment is introduced, a period of intense asteroid and comet impacts that may have contributed to Earth's water through the impact of icy comets. The script also mentions the formation of the first large landmass, Valara, and the earliest evidence of life on Earth, cyanobacteria, which would significantly alter the planet's atmosphere through photosynthesis.

05:02

🌱 The Rise of Cyanobacteria

Paragraph 2 delves into the impact of cyanobacteria, the earliest life forms with evidence in the fossil record. These microbes, living in colonies along coasts and riverways, used photosynthesis to create nutrients, thriving in the carbon dioxide-rich atmosphere. As they proliferated, they began to change the global climate by consuming CO2 and producing oxygen, leading to a drop in temperatures and the Earth's first glaciation. The script highlights how these organisms dominated the Archean Earth, forming complex microbial ecosystems and contributing to the formation of the first supercontinent, Kenorland. The cyanobacteria also adapted to dry land, turning the land green for the first time with microbial mats.

10:05

🌐 The Archean Eon's Legacy

The final paragraph summarizes the Archean Eon, noting that Earth now has a moon, a solid crust, abundant water, and fluctuating climates with increasing oxygen levels, largely due to cyanobacteria. The script humorously suggests that the narrator might remain in the Archean to join the 'Empire of Goo' but then expresses a desire to evolve into a human. It ends with a plea for viewers to subscribe to help the narrator 'evolve' by reaching certain subscriber milestones, which are humorously tied to the evolutionary journey of life on Earth.

Keywords

💡Archean Eon

The Archean Eon is the earliest part of Earth's history, spanning from approximately 4 billion years ago to 2.5 billion years ago. It represents the time when Earth was undergoing significant geological and atmospheric changes. In the video, the Archean Eon is highlighted as a period of intense meteorite bombardment, the formation of the first supercontinents, and the emergence of early life forms. The script mentions how this era is divided into eras, with each having its own unique characteristics and developments.

💡Late Heavy Bombardment

The Late Heavy Bombardment refers to a hypothesized period of intense asteroid and comet impacts on Earth and the Moon's surface around 4.1 to 3.8 billion years ago. This concept is crucial in the video as it is believed to have contributed to the delivery of water to Earth in the form of ice within comets, which would have had profound implications for the development of life. The script describes this period as having a significant impact on the Earth's early environment.

💡Cyanobacteria

Cyanobacteria, also known as blue-green algae, are some of the earliest known life forms on Earth. They are mentioned in the video as single-celled organisms that played a pivotal role in Earth's history by performing photosynthesis, which released oxygen into the atmosphere. This process is believed to have contributed to the Great Oxygenation Event, a critical turning point in the planet's atmospheric composition. The video script uses the term to illustrate the transformative impact of these early organisms on Earth's climate and environment.

💡Photosynthesis

Photosynthesis is the process by which plants, algae, and certain bacteria convert light energy into chemical energy, typically with the presence of chlorophyll, releasing oxygen as a byproduct. In the context of the video, photosynthesis is discussed as a key process that allowed cyanobacteria to thrive and significantly alter the Earth's atmosphere by increasing oxygen levels, which in turn led to a cooler climate and the first ice age.

💡Supercontinent

A supercontinent is a landmass comprising multiple continents that have merged together. The video discusses the formation of two supercontinents during the Archean Eon, named Valara and Kenorland. These supercontinents are significant as they represent major geological events and changes in the Earth's crust, which set the stage for the diversification of life and the development of more complex ecosystems.

💡Valara

Valara is the name given to one of the first supercontinents that formed during the Archean Eon, approximately 3 billion years ago. It is believed to have comprised parts of what is now Western Australia and South Africa. The video script uses Valara as an example to illustrate the early stages of continental formation and the potential environments in which early life could have developed.

💡Kenorland

Kenorland is another supercontinent that formed during the Archean Eon, around 2.7 billion years ago. It is mentioned in the video as an example of the Earth's dynamic geological history, where landmasses come together and drift apart over vast periods of time. Kenorland's formation is significant as it represents a stage in Earth's development where life could have begun to diversify and spread across larger land areas.

💡Great Oxygenation Event

The Great Oxygenation Event (GOE) refers to the period when oxygen started to accumulate in Earth's atmosphere as a result of photosynthesis by early life forms like cyanobacteria. This event is pivotal in the video's narrative as it marks a critical shift in the composition of Earth's atmosphere, leading to a cooler climate and the possibility of more complex life forms. The script describes how cyanobacteria played a key role in this event by producing oxygen as a byproduct of photosynthesis.

💡Glacial Period

A glacial period is a time of extensive glaciation, where ice sheets and glaciers cover large areas of the Earth's surface. The video discusses the first glaciation at the poles around 2.9 billion years ago, which was a result of the cooling effect caused by the increase in atmospheric oxygen due to cyanobacteria. This period is significant as it marks a major climate shift and sets the stage for further climatic changes and the evolution of life.

💡Stromatolites

Stromatolites are layered, dome-shaped structures formed by the growth of cyanobacteria in shallow water. They are mentioned in the video as evidence of early life on Earth, with some still existing today in places like Shark Bay, Australia. Stromatolites are significant as they provide a window into the past, showing how early life forms contributed to the formation of distinct geological structures and influenced the Earth's ecosystems.

Highlights

The Aran Eon began around 4 billion years ago during a period of heavy asteroid and comet impacts.

Comets, unlike asteroids, are made up mostly of dust and ice, contributing to Earth's water.

The late heavy bombardment period occurred between 4.1 to 3.8 billion years ago.

The Paleoarchean era started 3.6 billion years ago, marked by the formation of the first large landmass, Valara.

The earliest evidence of life, cyanobacteria, appeared during the Paleoarchean era.

Cyanobacteria used photosynthesis, which significantly altered the Earth's atmosphere.

The Mesarchean era saw the beginning of plate tectonics and the formation of supercontinents.

Cyanobacteria's photosynthesis led to a drop in global temperatures and the first glaciation.

The Neoarchean era marked the peak of cyanobacteria's dominance and the beginning of life on dry land.

The supercontinent Kenorland formed during the Neoarchean era.

Cyanobacteria still exist today, including in some niches like the atmosphere.

The Aran Eon laid the foundation for Earth's moon, solid crust, water, and fluctuating climate.

The geological record becomes more complete as we approach the present day.

The video humorously suggests that subscribing and sharing can help the narrator 'evolve' back to human form.

Stromatolites, ancient structures formed by cyanobacteria, are still alive today in places like Shark Bay, Australia.

The video provides a detailed timeline of Earth's history during the Aran Eon.

The Aran Eon is divided into eras, each with distinct geological and biological events.

Transcripts

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what the crap

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a so in our last video we started our

Journey exploring the complete history

of life on Earth we talked about how our

world was born as well as what it was

like for the first 600 million years of

its development in short it wasn't

pretty lava a toxic atmosphere and

constant bombardment from other objects

in the inner solar system were just part

of daily life on Earth during that time

but things were starting to slowly

improve on this little red marble as we

enter the Aran Eon and this is a stretch

of time that's three times longer than

the stretch of time that we covered in

the last one by the time we get to the

end of this video will be about halfway

through the complete history of the

earth and luckily we have a little bit

more information to go on than we did

last time but as I said before this will

probably be the case with every video

going forward because the closer we get

to the present day the more complete our

geological record is and for the first

time we now have enough data to actually

divide this Eon into eras however we

still don't know enough about this time

to Merit giving each era its own

individual video but we'll get to that

point soon enough so now let's get into

it because we still have a long way to

travel and before things get better it

looks like things are going to have to

get a lot

worse the EO Kean began around 4 billion

years ago as the Earth was in the throws

of a major crisis now we've already

talked about how our planet has had to

deal with constant barges of impacts

from other objects in our solar system

including the major impact that would

lead to the formation of the moon but

sometime before the end of the hadian

there would be a drastic increase in the

frequency of impacts from asteroids and

comets so much so that from 4.1 to 3.8

billion years ago we enter a time that

has come to be referred to as the late

heavy bombardment some estimates

calculate that there may may have been

as many as a few substantial impacts

every Millennium or so this might sound

like a bad thing and it probably would

be had we actually been there to witness

this event taking place but in all

actuality it may have had long-term

effects that led to our world becoming

one step closer to the Earth we know

today you see comets are not just solid

chunks of rock like asteroids they're

actually made up of mostly dust and ice

and as you may know

ice is frozen water and although there

was water on Earth already not nearly as

much as a 70% that we have covering the

planet today is believed that a large

percentage of the water we have arrived

in the form of cosmic snowballs being

hucked at us every few centuries now

this is one of the main things that

scientists have come to Define this era

by and even though this event would

start to slow down by 3.8 billion years

ago as the moon got further and further

away from the earth recent evidence has

led many to believe that there may have

been at least one impact around the size

of the one that wiped out the dinosaurs

on average every 15 million years

throughout the entire

archan starting at 3.6 billion years ago

we come to the Paleo archan an era

lasting around 400 million years this

time has been defined by two major

events that we know of so far the first

one being as the SE sea level Rose and

the crust of the earth began to cool the

first large land mass would form now we

can't know exactly what this land mass

actually looked like but we know that it

was at least partly made up of Western

Australia and South Africa it was given

the name valara and on its Coast would

be the most important step in the

history of our planet yet we have at

last arrived at the earliest evidence of

life now there's a very good chance that

single celled life had at least existed

for millions of years before this but

this is the earliest evidence that has

been found in the fossil record and it

might not seem like much but it's

believed that these little microbes

called cyanobacteria would make a

massive change to the entire world

simply by doing what they do for those

of you who play Spore we've officially

now entered the cell phas these little

guys lived in colonies and were

constantly expanding along the coasts

and eventually into the riverways of

albera they created their own nutrients

using

photosynthesis a process that works so

well that has been passed down to all

living plants today thriving in the

carbon dioxid Rich atmosphere these

first organisms would arguably become

Earth's very first

rulers you know I suddenly feel proud to

be a Cy

bacteria don't judge

me as we get into to the mesarch and

around 3.2 billion years ago we start to

see a new phenomenon take place as a

result of the cooler surface temperature

of the ground with the still active

volcanism underneath plate tectonics

begin to move the crust around the globe

causing continents to tear apart and

form together to form

supercontinents by this point the global

temperature had already dropped

considerably from what it was back in

the hian but it still isn't what we

would call comfortable by today's

standards around 50° C or 122° F and 85°

C or 185° F was the average at this time

this was probably the case because the

atmosphere was still mostly comprised of

greenhouse gases like methane and the

previously mentioned carbon dioxide that

was fueling the cyanobacteria Empire but

this was something that would actually

start to change as the current rule of

the archan earth spread and diversified

into different species and started to

form complex microbial ecosystems as the

cyano bacteria took over they would

start to do something that we normally

think of as only something that humans

are capable of drastic changes to the

global climate and they basically did

this simply by existing you see as these

microorganisms took in CO2 they would

produce oxygen as a byproduct this would

lead to a drop in temperatures until

eventually by 2.9 billion years ago the

earth would experience its very first

glaciation at the poles so in about half

a billion years the cyanobacteria took

over the world and made the hyper

Greenhouse climate cooler until Earth

was basically experiencing its very

first ice age that's a lot of

accomplishment for what is basically

mats of green goo excuse me sir have you

learned of the glory of

the ice would not become a permanent

fixture by 2.7 billion years ago it had

already completely receded I say already

like we're not talking about 200 million

years of cold this marks the beginning

of the fourth and final era of the Aran

the neoarchean and the cyano bacteria

had made the world theirs evolving into

new niches and covering different

environments all over the globe and

let's not get Twisted these guys were

also the first organisms to adapt to dry

land as well as the microbial mats

spread across the continents and Islands

it's thought that the land would

actually start to turn green for the

first time not with true plants yet but

with microbial mats made up of trillions

of tiny organisms who have managed to

make the planet theirs and over the

millions of years that followed the land

masses would come together to form the

first land that wasar large enough to be

considered a super continent We Now call

this continent kerland and it was well

it well it was largely empty with the

exception of the green goo slowly

spreading across it almost like a moldy

jelly just kind of slurk and across

there well even though there actually

wasn't mold yet it's all quite beautiful

isn't it it's amazing how sci-fi some of

this stuff seems as I research these

different times in Earth's past as

really easy to seem like we're just

glossing over everything and to be

honest we are and this is because now

covering the first 50% of Earth's

existence were still lacking a lot of

the fossil record to be able to

accurately know everything that was

going on during this Eon the fossils

from the once proud cob bacterian Empire

can now only be found in places like

Shark Bay Australia they're called

stromatolites and the top layers of

these bulbs of rock are actually still

alive that's right the cyano bacteria

still continue to exist 2 and 1/2

billion years after their reign as the

microbial rulers of this world came to

an end and cyanobacteria actually still

exists today and a bunch of other niches

including some kinds even living in our

atmosphere floating in the air today and

now we've come to the end of the archan

Eon as I said we are now already halfway

home and from from here things are going

to start to get a little bit more

complex but to recap our planet now has

a moon a solid crust with abundant water

on its surface the first two

supercontinents have come together and

been torn apart we have a climate that's

starting to fluctuate and oxygen is

becoming more and more abundant all the

time and much of this was thanks to the

mighty cyob bacterian Empire you know

maybe I should just stay like this maybe

I should just remain in the Aran and

join a giant mass of Goo for the glory

of the

Empire wait what am I saying this

sucks I have to try to get back to

becoming a human I have to get back to

my own time and after Consulting the

Pokedex I think I know how I evolved

into this form by reaching 1,500

subscribers while being next to those

hydrothermal vents at the end of the

hian remember so maybe that's the key

maybe if I hit different Milestones of

subscribers while in the right location

I'll evolve to the next stage of my

Evolution and eventually become human

again okay so I know that this is

something that you're probably all used

to hearing all the time but this just

became way more important if you made it

to this point in the video and you're

not already please for the love of God

subscribe and if you are subscribed

already share this or any of my other

videos to other people so they can

subscribe I need everyone's help to move

forward through time and turn back into

me again

until I reach the next Milestone I have

to stay here with this Colony otherwise

I'll dry out and

die please seriously these guys suck all

they do is talk about the glory of the

goo until then I'll just have to wait

here take care

everybody pray for me

h h

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