1. The History of Earth

2. The Big Bang
By measuring the rate at which all galaxies are moving away from each other, it can be calculated that everything in the universe existed in an infinitely small single point called a singularity about 13.7 bya
Using a branch of physics called quantum mechanics, it can be shown how a singularity such as the one that caused the Big Bang can spontaneously come into existence
Within milliseconds, this singularity suddenly split into energy and dark energy that exploded away in all directions
Much of the normal energy was converted into matter as it moved away from the singularity (E=mc2)
The dark energy from the Big Bang permeates throughout the universe and continues to propel galaxies away from each other to this day

3. Formation of Galaxies
Around 1 billion years after the big bang, gravitational pull caused matter floating throughout the cosmos to begin clumping together
As these clumps of matter began to get extremely dense, high pressures caused hydrogen fusion reactions to initialize in their cores, giving birth to stars
These stars began orbiting around super-massive black holes giving rise to galaxies

4. The Milky Way Around 200 Billion galaxies are estimated to exist
Our galaxy is known as the Milky Way
billion stars, 50 billion planets, 500 million within habitable zone of mother star (all estimates)
Closest galaxy is the Andromeda Galaxy 2.5 million light years away

5. The Solar System
Sometimes a massive star can go supernova ejecting a huge amount of matter into space creating a nebula
Nebula matter consists of the 92 naturally occurring elements in different ratios that were created under high pressures within the supernova
Over time, one such nebula began to collapse under its own gravitational pull and created our solar system around 4.6 billion years ago

7. Formation of the Earth & Moon
Within the accretion disk that was left around our sun, Earth Mark 1 formed within the habitable zone
30-50 million years afterwards, a 5th inner planet, known as Theia, collided with Earth Mark 1 ejecting molten rock into orbit
This rock formed temporary rings around what was now Earth Mark 2
Within another 100 years or so, the rings coalesced into the moon

8. Importance of the Moon
The moon is extremely important because its gravitational influence stabilizes our rotation on a 23.5° axial tilt
Without the moon, our axial tilt would fluctuate between 0° and 90° wreaking havoc on our climate
The earth wobbles 360° around this tilt once every 26,000 years
Within every 30° of this 360° rotation, the earth lines up with a Zodiac constellation
This occurs once every 2160 years on the winter solstice
This “Precession of the Ages” will begin again on 12/21/2012 marking the end of the Age of Pieces and the beginning of the Age of Aquarius

9. Timeline of the Earth
The history of the earth is divided into 4 Eons that cover the entire 4.6 billion year existence of the planet
The first 3 Eons are known collectively as the Precambrian and cover 90% of earth’s history
The last Eon is divided into 3 Eras that are further divided into Periods
The two Periods in the most recent Era are further divided into Epochs

10. The Hadean Eon
bya
Time before there was a solid surface on the earth
The moon formation event and the late-heavy bombardment occurred during this time
The inner planets were bombarded by comets and asteroids that presumably brought most of the earth’s water as well as amino acids necessary for life to form

11. The Archean Eon
bya
Began with the formation of the first solid rock and ended with the continents fully formed (though not in the present shape or distribution)
Earth was still very hot due to core heat, volcanism, and radioactive decay
Prokaryotic life began in the time around the boundary between the Hadean and Archean Eons

12. The Archean Eon
Late in the Eon, photosynthesis evolved and stromatolites, the most ancient organisms still living on the planet, began pumping O2 into the atmosphere
Most of the O2 was pulled down into the oceans that were greenish brown due to high amounts of dissolved iron in the water
The iron fully oxidized (rusted out) and the oceans turned blue by the end of the Archean Eon

13. The Proterozoic Eon 2.5 bya - 542 mya
Marked by the major accumulation of O2 in atmosphere
Led to first eukaryotic life around 2 bya
Proliferation of photosynthetic organisms began to take too much CO2 out of the atmosphere cooling the poles and creating extra ice cover
An ice-albedo feedback caused global cooling on an unprecedented scale

14. Snowball Earth
At the end of the Proterozoic Eon the earth froze solid, as evidenced by glacial rock deposits in areas that were equatorial at the time
Once the earth was frozen, CO2 was no longer able to be utilized for photosynthesis and began to increase due to volcanism
Eventually, rising CO2 began to trap heat and the snowball earth melted marking the end of the Eon and the entire Precambrian as a whole

15. Snowball Earth

16. Multicellular Life
At the end of snowball earth, melting glaciers washed massive amounts of pulverized rock and minerals into the oceans providing fuel for another round of heavy photosynthetic activity
Rising O2 levels allowed single-celled organisms to start using excess O2 to begin building collagen and “gluing” themselves together
This was the beginning of multicellular life and can be seen in action if a sponge is passed through a sieve

17. Multicellular Life
Multicellular organisms had many advantages over their single-celled cousins
Cells could now work together to find food or defend against predation, or they could begin to differentiate and take over specific tasks
There were two major developments of multicellular life on earth – the first was not very successful and lasted only million years. The second led to all the present multicellular life forms on earth today

18. Fractal Organisms
The first multicellular life forms evolved as snowball earth was melting and grew by fractal, or modular construction
Their bodies were flat and were anchored to the sea floor in complete darkness
With no mouth or sensory structures, these organisms simply absorbed nutrients through their thin, flat bodies

19. Fractal Organisms
The most common fossil of fractal organisms is called Charnia
It appears all over the world in rock that is around 560 million years old and was deep underwater at the time of its formation
Due to fractal construction, it and others like it were unable to evolve into more complex life forms and were out-completed by organisms that were to be our ancestors
The fractal organism life line ceased at the end of the Proterozoic Eon

20. The Phanerozoic Eon 542 mya – Present
Divided into 3 Eras – The Paleozoic, Mesozoic, and Cenozoic Eras
The ends of the Paleozoic and Mesozoic Eras were marked by mass extinctions
The Cenozoic Era is still continuing today

21. The Paleozoic Era
542 – 251 mya
Began with the Cambrian Period and ended with the Permian Period
The Paleozoic Era was marked by the evolution of most modern animal phyla, the formation and break-up of several supercontinents, and the colonization of land by plants and animals

22. The Cambrian Explosion
With the uptick in atmospheric O2 at the end of snowball earth, multicellular life began to evolve extremely rapidly
Within a few million years, organisms began to develop mobility and the first modern animals were born
Future generations began to evolve features like teeth and claws that allowed them to become more successful hunters and their prey followed suit by developing defensive structures like shells

23. The Cambrian Explosion
This “arms race” fueled evolution’s progress and within 20 million years of the beginning of the age, all present animal phyla had evolved
This event that marked the 20 million year span of rapid evolutionary development is known as the Cambrian Explosion
The best place in the world to see evidence of this is the Burgess Shale in the Canadian Rockies of British Colombia

24. Periods of the Paleozoic
Cambrian – explosion of life
Ordovician – adaptive radiation of animal phyla formed during the Cambrian including the formation of vertebrates
Silurian – major arthropod advancements and beginning of land plants
Devonian – invertebrates and amphibians colonized land
Carboniferous – large swamp forests that led to all coal formations today and the development of land reptiles
Permian – proto-mammals evolved out of reptiles

25. The P-T Extinction Event
At the end of the Permian Period, the climate of the earth began changing
The formation of Pangaea created a super-desert over much of the land on earth and caused oceanic currents to change altering the weather and rain cycles severely
Then, 251 mya, a super-volcano in present-day Siberia erupted causing a “nuclear winter” that lasted years
Many species already in trouble due to environmental pressures caused by Pangaea could not survive the conditions over the next few years and 83% of all genera on the planet were wiped out

26. The Mesozoic Era
mya
Marked on both sides by the two largest extinction events in history
The “Age of the Dinosaurs”
The P-T Extinction at the end of the Permian allowed for massive adaptive radiation of remaining species
Broken into 3 Periods – The Triassic, Jurassic, and Cretaceous

27. The Triassic Period 250-200 mya
Began at the end of the Permian-Triassic Extinction event
Pangaea remained intact throughout the Triassic
The first dinosaurs evolved during the mid-Triassic including Pterosaurs and the small Coelophysis and their relatives
Advanced Cynodonts gave rise to the first mammals midway through the Triassic as well

28. The Jurassic Period 200-145 mya
Beginning of Jurassic is marked by the initial breakup of Pangaea into the two supercontinents Laurasia and Gondwanaland
Large herbivorous dinosaurs like the brontosaurus, marine dinosaurs like the ichthyosaurs, and pterosaurs were the dominant dinosaurs at this time
Mammals were small and insignificant
End of Jurassic was marked by the appearance of flowering plants on earth
Triassic/Jurassic

29. The Cretaceous Period 145-65 mya
Dinosaurs evolved into their peak diversity during the Cretaceous
T-Rex, Triceratops, Velociraptor, and modern birds all evolved
Laurasia and Gondwanaland broke up into the today’s continents, but they were not yet in their present positions
The Cretaceous and the entire Mesozoic Era came to an end with an asteroid impact near the present-day Yucatan Peninsula

30. The K-T Extinction Called the Cretaceous-Tertiary Extinction event
The asteroid impact threw ash into the atmosphere blocking out most sunlight for years
Most photosynthetic plants died, leaving no food for the large herbivorous dinosaurs that required massive amounts of energy daily
All non-avian dinosaurs, pterosaurs, and marine reptiles perished along with many other species
When the ash settled, the stage was finally set for mammals to take over the earth

31. The Cenozoic Era 65 mya – Present The “Age of Mammals”
Continents moved into their present positions
The movement of Antarctica to the south pole and the joining of South America to North America altered oceanic currents and led to global cooling
Forest swamps of the Mesozoic Era gave way to large areas of grasslands in the Cenozoic Era

32. The Cenozoic Era
Mammals diverged from a few small, generalized forms to the plethora of terrestrial, marine, and flying types of the present
Birds diversified and flowering plant/insect relationships developed as well
Snakes and modern lizards, the newest reptiles evolved during the Cenozoic
The Cenozoic Era is divided into 3 Periods

33. Periods of the Cenozoic
The Paleogene Period
65-23 mya
The most significant evolution of birds and mammals occurred in the Paleogene
Ended with a minor extinction event affecting mammals
The Neogene Period
mya
Creation of the Panama Isthmus and the resulting global cool-down were the defining events of the period

34. Periods of the Cenozoic
The most recent Period of history is the Quaternary (2.5 mya- Present)
Marked by the rise of Homo sapiens
Though primates had been evolving since the K-T Extinction 65 mya, the Homo line had been evolving since the Neogene Period 6-7 mya
During the Quaternary, Homo neanderthalensis, Homo erectus, and Homo sapiens all fought for resources and interbred until the present form of humans were the only species left by 30,000 years ago

35. Periods of the Cenozoic
The Quaternary is divided into two important Epochs
The Pleistocene
2.5 mya - ~12,000 years ago
The Ice Ages
Marked by 11 known glaciations that covered 30% of the earth’s surface at each maximum
Glaciations as well as development and subsequent predation by humans drove most mega-mammals to extinction
The Holocene
~12,000 years ago – Present Day
Considered an interglacial period during the present ice ages
All of humanity has occurred in this brief warm period of time, roughly % of the history of the world

36. The Future of the Earth
The Earth will not remain a planet conducive to human life forever
Many changes are expected to occur over the next 7.5 billion years until the Earth is ultimately destroyed by our sun

37. The Next Ice Age
Greenhouse gasses will rise until all fossil fuels run out by ~2200 AD
The next ice age is expected to begin 25,000 years from now, but global warming may only delay the onset for 5,000 years or so
Human civilization would have to adapt dramatically to survive the glaciation event that would last tens of thousands of years

38. Future Supercontinents
Plate tectonics will continue until the earth’s core cools past a point necessary for mantle convection to occur
Two theories predict the next supercontinent that will be produced in ~250 million years
Introversion Theory predicts that the Atlantic and Indian oceans would widen until new subduction zones form causing them to collapse forming Pangaea Ultima
Extroversion Theory predicts that the Atlantic will continue to expand and the Pacific will continue to contract until the Americas collide with Asia and create Amasia or Novopangaea

39. Future Supercontinents
The formation of a new supercontinent would alter the entire climate of the earth in unforeseen ways
Eventually the core of the earth will cool to a point where continental drift will cease
The dynamo effect of the spinning metallic core of the earth would continue for millions of years after the continents stop moving
Eventually the core will stop spinning all together causing the magnetic field around the earth to break down
Solar radiation would then begin bombarding the earth destroying DNA at the cellular level putting all life on earth in jeopardy

40. Earth Becomes Like Venus, Then Mars
As the sun ages and solar output increases the temperature on the earth will eventually rise
Once the sun is 10% more powerful than today (1.1 billion years from now) it will begin evaporating the oceans into the atmosphere
The atmosphere will become saturated with water, a greenhouse gas, and a runaway greenhouse planet like Venus will form
Once the magnetic field breaks down, the solar winds will blow the water/atmosphere out into space leaving a dead, dry planet like Mars

41. Future of the Moon
The moon is very large to earth when compared with other planets/moons
The moon is slowing down the spin of the earth by way of tidal braking
At the same time, the tidal braking is also speeding up the orbit of the moon causing the moon to move away from the earth 1 inch further each year
Eventually, tidal breaking will cease when the moon’s orbit and the earth’s day both equal 47 modern days in length, about 3 billion years from now
Once the moon is this far away, it will lose its ability to stabilize the earth on its axis
The earth would begin to tumble in its orbit and the climate would never be stable again

42. Red Giant
The hydrogen core of the sun will begin to run out of fuel in the next 6-7 billion years or so
As this happens, the sun will begin to consume the hydrogen in its outer regions
This will cause the outer regions of the sun to expand rapidly until the edge of the sun reaches about as far as earth’s present orbit
The earth may not actually be swallowed up by the sun, but its luminosity is expected to increase to 2,730 times its present power essentially cooking the earth

43. Fate of the Solar System
The sun does not have enough mass to become a supernova and explode to seed a new solar system
Instead, once the sun enters the red giant phase, it will begin to throw its mass out into space until its white-hot core is all that is left
This white dwarf will enter its final phase of life once it has cooled to the point that no more light is emitted
At this point, it will be a black dwarf or a mini black hole

44. Fate of the Universe The Big Freeze The Big Crunch
Theory that proposes that our universe is open and will continue to expand and lose heat until it is completely dark and everything in the universe is at absolute zero
The Big Crunch
Theory that proposes that the mass of the universe will eventually overpower its expansion and it will contract back to a singularity similar to the one that brought about the Big Bang
This theory predicts a closed, oscillatory universe that cycles in and out of existence