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The earth started from a nebula
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A nebula when in the right conditions will explode in which its effects create a planet, in which case planet earth
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earth is made into a molten state in which then it starts to cool down to make its solid form
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Earth is nw formed along with its solor system including the sun
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Water vapor condenst and fell as rain which then formed into pools and large bodies of water.
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Once liquid water was present organic compounds were able to form from inorganic materials.
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The origins and earliest evolution of this diverse group, which includes clams, snails, squid, and octopuses, remain unclear. Descended from annelids, monoplacophorans lacked eyes and moved on a rounded foot under a simple, limpet-like shel.
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The oldest vertebrate species were discovered in the 1990s in 530-million-year-old shale fossil beds in China, where scientists uncovered two types of tiny jawless fish they named Haikouichthys and Myllokunmingia.
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the age of abundant and diverse life on earth, including the Paleozoic, Mesozoic and Cenozoic eras
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beginning with an explosion of the diversity of life, with most animal phyla appearing withing the first few million years of the era, and ending with a mass extinction of many species, about 248 million years ago
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The ancestors of sharks first swam about 450 million years ago. Known as cartilaginous fish because their skeletons were made of cartilage, not bone, sharks and rays left very few early fossils.
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Scorpions are thought to be the oldest arachnids, appearing around 430 million years ago. Some marine species were huge, with one recently discovered fossil specimen estimated to be some 8.2 feet (2.5 meters) long.
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Plants began to take root on land about 430 million years ago. The transition from water presented plants with a difficult evolutionary challenge. Their solution was a vascular system of tubelike tissues for transporting water and nutrients on dry land.
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Amphibians started hauling themselves out of the water about 370 million years ago. The first vertebrates to walk on land, they evolved from air-breathing fish that waddled in the shallows on strong, limblike fins.
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During the Carboniferous, the Earth's major landmasses started coming together to create a single, vast supercontinent known as Pangaea.
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The Carboniferous period is named after its carbon-rich coal deposits formed from the remains of lush swamp forests that covered low-lying coastal regions.
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The earliest reptiles had evolved from amphibians by 300 million years ago. Known as anapsids, they outwardly resembled modern-day lizards, though there were key internal differences, including an amphibian-like skull that lacked holes except for the nostrils and eyes.
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The age of the dinosaurs dawned arounded 240 million years ago—the time to which the oldest known dinosaur dates. Identified from fossil fragments in Madagascar,
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The giant supercontinent of Pangaea began breaking up toward the end of the Triassic. The process started with Europe's separation from Africa, leaving a widening breach filled by the so-called Tethys Ocean.
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The Permian period climaxed in the largest mass extinction in Earth's history. About 95 percent of marine species and 70 percent of land animals were wiped out. Climate change is the main reason.
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Mammals emerged from the massive decline of their immediate ancestors, the therapsid mammal-like reptiles. The few therapsids that managed to survive the Permian mass extinction included mini, burrowing species that scientists think may have been warm-blooded and covered in insulating fur.
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The Earth was a suffocating place until oxygen in the atmosphere slowly began to climb from almost nonexistent levels about 2.5 billion years ago. Breathable air is thought to have been created by cyanobacteria, single-celled microbes living in the sea.
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Dinosaurs rule and rein the earth for almost 150 million years
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Flowering plants bloom in the fossil record about 125 million years ago, the oldest known examples coming from China. The plants probably first took root in the Jurassic, but it wasn't until the Cretaceous that they flourished, encouraged by a predominately warm, mild climate.
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Birds became airborne around 150 million years ago, the earliest record was from a well-preserved fossil discovered in Germany in 1861. The fossil showed a creature with unmistakable wing feathers but also reptilian features, such as a bony tail, arm claws, and sharp teeth.
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Hominins—humans and their immediate ancestors—are thought to have split from the lineage that also gave rise to modern chimpanzees between six million and eight million years ago.
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Earth's history have been dominated by a series of ice ages of varying intensity, the most recent ending some 10,000 years ago. The coldest of these glacial episodes lasted tens of thousands of years, when massive ice sheets spread as far south as New York and London. Linked to factors including variations in the planet's orbit around the sun, these ice ages saw the rise of a range of distinctive animals such as mastodons, woolly mammoths, and woolly rhinos, all now extinct. Others, such as the
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With the dinosaurs suddenly gone, tiny mammals stepped into their big shoes, rapidly diversifying and growing in size as the animals filled newly vacant ecological niches.
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it is unclear exactly when the first primates appeared. While teeth remains suggest their emergence could date as far back as the late Cretaceous, the earliest certain primate fossils are about 55 million years old.
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The end of the Cretaceous, 65 million years ago, was signaled by a massive extinction event that wiped out the non-avian dinosaurs. Up to 50 percent of the planet's animal and plant species disappeared. Other victims included giant marine reptiles, mosasaurs, and the flying pterosaurs.
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Fossils indicate our own species, Homo sapiens, arose in eastern Africa some 190,000 years ago. First venturing beyond Africa about 70,000 years ago, early modern humans eventually penetrated as far as Australia and South America.
