History of the World

This is the history of the world.

4.5 billion years ago
The Earth is formed out of debris around the solar protoplanetary disk. There is no life. Temperatures are extremely hot, with frequent volcanic activity and hellish environments. The atmosphere is nebular. Possible early oceans or bodies of liquid water. The moon is formed around this time, probably due to a protoplanet's collision into Earth.

4.0 to 2.5 billion years ago
Prokaryote life, the first form of life, emerges at the very beginning of this eon, in a process known as abiogenesis. The continents of Ur, Vaalbara and Kenorland may have been formed around this time. The atmosphere is composed of volcanic and greenhouse gases.

2.5 billion years ago to 541 million years ago
Eukaryotes, a more complex form of life, emerge, including some forms of multicellular organisms. Bacteria begin producing oxygen, shaping the third and current of Earth's atmospheres. Plants, later animals and possibly earlier forms of fungi form around this time. The early and late phases of this eon may have undergone "Snowball Earth" periods, in which all of the planet suffered below-zero temperatures. The early continents of Columbia, Rodinia and Pannotia may have formed around this time, in that order.

Cambrian Period
The Cambrian spans from 541 million years to 485 million years and is the first period of the Paleozoic era of the Phanerozoic. The Cambrian marked a boom in evolution in an event known as the Cambrian explosion in which the largest number of creatures evolved in any single period of the history of the Earth. Creatures like algae evolved, but the most ubiquitous of that period were the armored arthropods, like trilobites. Almost all marine phyla evolved in this period. During this time, the supercontinent Pannotia begins to break up, most of which later became the supercontinent Gondwana. It is also one of the earliest time periods that humans and other sapient species went to, bringing back some individuals of species that lived during this time period, eventually, introducing many species from the Cambrian Period to modern day waterways.

Ordovician Period
The Ordovician spanned from approximately 485 million years to approximately 443 million years ago. The Ordovician was a time in Earth's history in which many of the biological classes still prevalent today evolved, such as primitive fish, cephalopods, and coral. The most common forms of life, however, were trilobites, snails and shellfish. More importantly, the first arthropods went ashore to colonize the empty continent of Gondwana. By the end of the Ordovican, Gondwana was at the south pole, early North America had collided with Europe, closing the Atlantic Ocean. Glaciation of Africa resulted in a major drop in sea level, killing off all life that had established along coastal Gondwana. Glaciation may have caused the Ordovician–Silurian extinction events, in which 60% of marine invertebrates and 25% of families became extinct, and is considered the first mass extinction event and the second deadliest.

Silurian Period
The Silurian spanned from 443 to 416 million years ago. The Silurian saw the rejuvenation of life as the Earth recovered from the previous glaciation. This period saw the mass evolution of fish, as jawless fish became more numerous, jawed fish evolved, and the first freshwater fish evolved, though arthropods, such as sea scorpions, were still apex predators. Fully terrestrial life evolved, including early arachnids, fungi, and centipedes. The evolution of vascular plants (Cooksonia) allowed plants to gain a foothold on land. These early plants are the forerunners of all plant life on land. During this time, there were four continents: Gondwana (Africa, South America, Australia, Antarctica, Siberia), Laurentia (North America), Baltica (Northern Europe), and Avalonia (Western Europe). The recent rise in sea levels allowed many new species to thrive in water.

Devonian Period
The Devonian spanned from 416 million years to 359 million years. Also known as "The Age of the Fish", the Devonian featured a huge diversification of fish, including armored fish like Dunkleosteus and lobe-finned fish which eventually evolved into the first tetrapods. On land, plant groups diversified incredibly in an event known as the Devonian Explosion when plants made lignin allowing taller growth and vascular tissue: the first trees evolved, as well as seeds. This event also diversified arthropod life, by providing them new habitats. The first amphibians also evolved, and the fish were now at the top of the food chain. Near the end of the Devonian, 70% of all species became extinct in an event known as the Late Devonian extinction and was the second mass extinction event the world has seen.

Carboniferous Period
The Carboniferous spanned from 359 million to 299 million years. During this time, average global temperatures were exceedingly high; the early Carboniferous averaged at about 20 degrees Celsius (but cooled to 10 ° C during the Middle Carboniferous). Tropical swamps dominated the Earth, and the lignin stiffened trees grew to greater heights and number. As the bacteria and fungi capable of eating the lignin had not yet evolved, their remains were left buried, which created much of the carbon that became the coal deposits of today (hence the name "Carboniferous"). Perhaps the most important evolutionary development of the time was the evolution of amniotic eggs, which allowed amphibians to move farther inland and remain the dominant vertebrates for the duration of this period. Also, the first reptiles and synapsids evolved in the swamps. Throughout the Carboniferous, there was a cooling trend, which led to the Permo-Carboniferous glaciation or the Carboniferous Rainforest Collapse. Gondwana was glaciated as much of it was situated around the south pole.

Permian Period
The Permian spanned from 299 to 252 million years ago and was the last period of the Paleozoic Era. At the beginning of this period, all continents joined together to form the supercontinent Pangaea, which was encircled by one ocean called Panthalassa. The land mass was very dry during this time, with harsh seasons, as the climate of the interior of Pangaea was not regulated by large bodies of water. Diapsids and synapsids flourished in the new dry climate. Creatures such as Dimetrodon and Edaphosaurus ruled the new continent. The first conifers evolved, and dominated the terrestrial landscape. Near the end of the Permian, however, Pangaea grew drier. The interior was desert, and new species such as Scutosaurus and Gorgonopsids filled it. Eventually they disappeared, along with 95% of all life on Earth, in a cataclysm known as "The Great Dying", the third and most severe mass extinction.

Triassic Period
The Triassic ranges roughly from 252 million to 201 million years ago. The Triassic is a time in Earth's history bracketed between the Permian Extinction and the Triassic–Jurassic extinction event, two of the big five, and precedes the Jurassic Period. It has three major epochs: the Early Triassic, the Middle Triassic and the Late Triassic.

The Early Triassic was between about 252 million to 247 million years ago and was dominated by deserts as Pangaea had not yet broken up, thus the interior was nothing but arid. The Earth had just witnessed a massive die-off in which 95% of all life became extinct. The most common vertebrate life on earth were Lystrosaurus, labyrinthodonts, and Euparkeria along with many other creatures that managed to survive the Great Dying. Temnospondyls evolved during this time and would be the dominant predator for much of the Triassic.

The Middle Triassic spans roughly from 247 million to 237 million years ago. The Middle Triassic featured the beginnings of the breakup of Pangaea, and the opening of the Tethys Sea. The ecosystem had recovered from the devastation that was the Great Dying. Algae, sponge, corals, and crustaceans all had recovered, and the reptiles began to get bigger and bigger. New aquatic reptiles evolved, such as ichthyosaurs and nothosaurs. Meanwhile, on land, pine forests flourished, as did groups of insects like mosquitoes and fruit flies. The first ancient crocodilians evolved, which sparked competition with the large amphibians that had since ruled the freshwater world.

The Late Triassic spans roughly from 237 million to 201 million years ago. Following the bloom of the Middle Triassic, the Late Triassic featured frequent heat spells, as well as moderate precipitation (10-20 inches per year). The recent warming led to a boom of reptilian evolution on land as the first true dinosaurs evolved, as well as pterosaurs. During the Early Triassic, some advanced cynodonts gave rise to the first Mammaliaformes. All this climatic change, however, resulted in a large die-out known as the Triassic-Jurassic extinction event, in which many archosaurs (excluding pterosaurs, dinosaurs and crocodylomorphs), most synapsids, and almost all large amphibians became extinct, as well as 34% of marine life in the fourth mass extinction event of the world. The cause is debatable.

Jurassic Period
The Jurassic ranges from 200 million years to 145 million years ago and features 3 major epochs: The Early Jurassic, the Middle Jurassic, and the Late Jurassic.

The Early Jurassic spans from 200 million years to 175 million years ago. The climate was much more humid than the Triassic, and as a result, the world was very tropical. In the oceans, plesiosaurs, ichthyosaurs and ammonites were abundant. On land, dinosaurs and other archosaurs stake their claim as the dominant race of the land, with species such as Dilophosaurus at the top. The first true crocodiles evolved, pushing out the large amphibians to near extinction. All-in-all, archosaurs rise to rule the world. Meanwhile, the first true mammals evolve, remaining relatively small sized but otherwise expanding ecologically; the Jurassic Castorocauda, for example, had adaptations for swimming, digging and catching fish. Fruitafossor, from the late Jurassic period about 150 million years ago, was about the size of a chipmunk and its teeth, forelimbs and back suggest that it broke open the nest of social insects to prey on them (probably termites, as ants had not yet appeared). The first multituberculates like Rugosodon evolve, while volaticotherians take to the skies.

The Middle Jurassic spans from 175 million to 163 million years ago. During this epoch, dinosaurs flourished as huge herds of sauropods, such as Brachiosaurus and Diplodocus, filled the fern prairies of the Middle Jurassic. Many other predators rose as well, such as Allosaurus. Conifer forests made up a large portion of the forests. In the oceans, plesiosaurs were quite common, and ichthyosaurs were flourishing. This epoch was the peak of the reptiles.

The Late Jurassic spans from 163 million to 145 million years ago. During the Late Jurassic, the first avialans, like Archaeopteryx, evolved from small coelurosaurian dinosaurs. The increase in sea-levels opened up the Atlantic sea way which would continue to get larger over time. The divided world would give opportunity for the diversification of new dinosaurs.

Cretaceous Period
The Cretaceous is the longest period in the Mesozoic, but has only two epochs: the Early Cretaceous, and the Late Cretaceous.

The Early Cretaceous spans from 145 million to 100 million years ago. The Early Cretaceous saw the expansion of seaways, and as a result, the decline and extinction of sauropods (except in South America). Some island-hopping dinosaurs, like Eustreptospondylus, evolved to cope with the coastal shallows and small islands of ancient Europe. Other dinosaurs rose up to fill the empty space that the Jurassic-Cretaceous extinction left behind, such as Carcharodontosaurus and Spinosaurus. Of the most successful would be the Iguanodon which spread to every continent. Seasons came back into effect and the poles got seasonally colder, but dinosaurs still inhabited this area like the Leaellynasaura and Muttaburrasaurus which inhabited the polar forests year-round. Since it was too cold for crocodiles, it was the last stronghold for large amphibians, like Koolasuchus. Pterosaurs got larger as species like Tapejara and Ornithocheirus evolved. Mammals continued to expand ecologically; eutriconodonts produced fairly large, wolverine-like predators like Repenomamus and Gobiconodon, early therians began to expand into metatherians and eutherians, and cimolodont multituberculates went on to become large components of the fossil record.

The Late Cretaceous spans from 100 million to 66 million years ago. The Late Cretaceous featured a cooling trend that would continue on in the Cenozoic period. Eventually, tropics were restricted to the equator and areas beyond the tropic lines featured extreme seasonal changes in weather. Dinosaurs still thrived as new species such as Tyrannosaurus, Ankylosaurus, Triceratops and hadrosaurs dominated the food web. In the oceans, mosasaurs ruled the seas, filling the role of the ichthyosaurs, which, after declining, had disappeared in the Cenomanian-Turonian boundary event. Though pliosaurs had gone extinct in the same event, long necked plesiosaurs, such as Elasmosaurus, continued to thrive. Flowering plants, possibly appearing as far back as the Triassic, became truly dominant for the first time. Pterosaurs in the Late Cretaceous declined for poorly understood reasons, though this might be due to fossil record bias as their diversity seems to be much higher than previously thought. Birds became increasingly common and diverse, diversifying in a variety of enantiornithe and ornithurine forms. Though mostly small, marine Hesperornithes became relatively large and flightless, adapted to life in the open sea. Metatherians and primitive eutherian also became common and even produced large and specialised species like Didelphodon and Schowalteria. Still, the dominant mammals were multituberculates, cimolodonts in the north and gondwanatheres in the south. At the end of the Cretaceous, the Deccan traps and other volcanic eruptions were poisoning the atmosphere. As this was continuing, it is thought that a large meteor smashed into earth 66 million years ago, creating the Chicxulub Crater in an event known as the K-T Extinction, the fifth and most recent mass extinction event, in which 75% of life on earth became extinct, including most non-avian dinosaurs, with the exception of Troodons, Saurornithoides, Charonosauruses, Alamosauruses, and Opisthocoelicaudiaes, which had somehow survived extinction. Most terrestrial organisms over 10 kilograms became extinct. For the most part, the age of the dinosaurs was over.

Paleogene Period
Paleocene epoch ranged from 66 million to 56 million years ago. The Paleocene is a transitional point between the devastation that is the K-T extinction, to the rich jungles environment that is the Early Eocene. The Early Paleocene saw the recovery of the earth. The continents began to take their modern shape, but all the continents and subcontinent India were separated from each other. Afro-Eurasia was separated by the Tethys Sea, and the Americas were separated by the strait of Panama, as the isthmus had not yet formed. This epoch featured a general warming trend, with jungles eventually reaching the poles. The oceans were dominated by sharks as the large reptiles that had once ruled became extinct. Archaic mammals filled the world such as creodonts (extinct carnivores, unrelated to existing Carnivora) and early primates that evolved during the Mesozoic, and as a result, there was nothing over 10 kilograms. Mammals were still quite small.

Eocene Period
The Eocene Epoch ranged from 56 million years to 33.9 million years ago. In the Early-Eocene, life was small and lived in cramped jungles, much like the Paleocene. There was nothing over the weight of 10 kilograms, with the exception of troodonts, hadrosaurs, and sauropods. Among them were early primates, whales, horses, tapirs, and chalicotheres, along with many other early forms of mammals. At the top of the food chains were huge birds, such as Paracrax. The temperature was 30 degrees Celsius with little temperature gradient from pole to pole. In the Mid-Eocene, the Circumpolar-Antarctic current between Australia and Antarctica formed which disrupted ocean currents worldwide and as a result caused a global cooling effect, shrinking the jungles. This allowed mammals to grow to mammoth proportions, such as whales which, by that time, were almost fully aquatic. Mammals like Andrewsarchus were at the top of the food-chain. The Late Eocene saw the rebirth of seasons, which caused the expansion of savanna-like areas, along with the evolution of grass.

Oligocene Period
The Oligocene Epoch spans from 33.9 million to 23.03 million years ago. The Oligocene featured the expansion of grass which had led to many new species to evolve, including the first elephants, cats, dogs, marsupials and many other species still prevalent today. Many other species of plants evolved in this period too, such as the evergreen trees, with the exception of Conifers, which had originated during the Carboniferous and dominated during the Mesozoic era and still exist today. A cooling period was still in effect and seasonal rains were as well. Mammals still continued to grow larger and larger. Paraceratherium, the largest land mammal to ever live evolved during this period. In North America, the surviving dinosaurs such as Troodons have diversified into many different species, ranging from herbivorous species to carnivorous ones. The first mongooses in North America has evolved from from Asian mongooses that has taken the first steps into North America.

Miocene Period
The Miocene epoch spans from 23.03 to 5.333 million years ago and is a period in which grass spread further, dominating a large portion of the world, at the expense forests. Kelp forests evolved, encouraging the evolution of new species, such as sea otters. During this time, perissodactyla thrived, and evolved into many different varieties. Apes evolved into 30 species. The Tethys Sea finally closed with the creation of the Arabian Peninsula, leaving only remnants as the Black, Red, Mediterranean and Caspian Seas. This increased aridity. Many new plants evolved: 95% of modern seed plants evolved in the mid-Miocene. Some species such as the first dylanusids, Cetofelis, has evolved, then they evolved into the Lutonsotherium, then Homodon, and finally the first Dylanus has evolved, but only Dylanus has survived to present times.

Pliocene Period
The Pliocene epoch lasted from 5.333 to 2.58 million years ago. The Pliocene featured dramatic climactic changes, which ultimately led to modern species and plants. The Mediterranean Sea dried up for several million years (because the ice ages reduced sea levels, disconnecting the Atlantic from the Mediterranean, and evaporation rates exceeded inflow from rivers). Australopithecus evolved in Africa, beginning the human branch. The isthmus of Panama formed, and animals migrated between North and South America, wreaking havoc on local ecologies. Climatic changes brought: savannas that are still continuing to spread across the world; Indian monsoons; deserts in central Asia; and the beginnings of the Sahara desert. The world map has not changed much since, save for changes brought about by the glaciations of the Quaternary, such as the Great Lakes, Hudson Bay, and the Baltic sea. The first sapient species evolved in this time period, the Chalicoman, which evolved from a group of Chalicotheriums that became omnivorous and became upright bipedal walkers with sapience, the first time in Earth's history, but there are many more sapient species in later times such as humans.

Pleistocene
The Pleistocene lasted from 2.58 million to 11,700 years ago. This epoch was marked by ice ages as a result of the cooling trend that started in the Mid-Eocene. There were at least four separate glaciation periods marked by the advance of ice caps as far south as 40 degrees N latitude in mountainous areas. Meanwhile, Africa experienced a trend of desiccation which resulted in the creation of the Sahara, Namib, and Kalahari deserts. Many animals evolved including mammoths, giant ground sloths, dire wolves, saber-toothed cats, and Homo sapiens. Homo sapiens and few other apes in the genus Homo also diversified into many different species like Elecman.EXEs, animean humans, and among others. Some Dylanuses evolved into its sapient relatives such as Maverick Hunters, Protomen, and Bass.EXEs somewhere around 800,000 years ago. 100,000 years ago marked the end of one of the worst droughts of Africa, and led to the expansion of primitive man. As the Pleistocene drew to a close, a major extinction wiped out much of the world's megafauna, including some of the hominid species, such as Neanderthals. Most of the continents were affected, but Africa to a lesser extent. The continent retains many large animals, such as hippos.

Holocene Period
The Holocene began 11,700 years ago and lasts until to present day. All recorded history and "the history of the world" lies within the boundaries of the Holocene epoch. Human activity is blamed for a mass extinction that began roughly 10,000 years ago, though the species becoming extinct have only been recorded since the Industrial Revolution. This is sometimes referred to as the "Sixth Extinction". Over 322 species have become extinct due to human activity and some other sapient species activity since the Industrial Revolution. But today, things are different, people are now trying to protect all species of organisms, both endangered and non-endangered. Time Travel and Universe Travel was invented in this time period, saving all species of animals and plants from extinction and, for former fictional species, being brought to reality, and for the first time, overabundance of species types occurred, but rather than having negative impact, they have positive impact, preventing the further global warming caused by humans. North America and few other countries now allow all kinds of wildlife (native and nonnative, modern and formerly extinct, real and former fictional, and so on) to live alongside sapient species, not just in the wild, but also in cities, to conserve species for much longer, so harming any wildlife is against the law. However, one kind of creature is threatening all sapient species' existence, vampires, which were brought accidentally through universe travel by sapient species, have started the Vampire Wars, to prove who will rule Earth, humans, dylanuses, and alies, or vampires.