Due to Erwins research, it is now known that the first animal evolved during the Ediacaran and not the Cambrian like previously thought. The first lifeforms emerged at least 3.5 billion years ago. No rocks on the Earth are this old, except for meteorites. At first glance, an ichthyosaur looks much like dolphins that live today. When they grew in dense groups they created a protected, diverse ecosystem for other creatures to call home. The Hadean Eon, named after the Greek god and ruler of the underworld Hades, is the oldest eon and dates from 4.5-4.0 billion years ago. The name Hadean was coined by geologist Preston Cloud for the pre-Isuan sequence whose record may not be preserved on Earth but is better known from Moon rocks. At Smithsonian Ocean, we have lesson plans, activities, and resources to help you engage your students in the wonders of our oceans. During the Proterozoic Eon, modern plate tectonics became active, and the ancient cores of the continents moved . Variant organisms will leave offspring like themselves. because it was during this era that mammals became the dominant vertebrate animals on land. But as they evolved large crescent shape tails, similar to those of present-day tuna, they began to propel themselves by fanning only their tail. in any, geologic setting, the event or geologic feature which cuts across the most other features is the youngest . (ed.) Its prey consisted of trilobites and other smaller animals crawling on the seafloor. Scientists know this through the discovery of ancient zircon crystals that were dated around this time. Baleen whales didnt begin to get really big until roughly 5.3 million years ago, at the transition between the Miocene and the Pliocene. But unlike many of its relatives, one species of anomalocarid doesn't seem to be an apex predator. Pollution from runoff, oil spills, and plastic waste are killing species at an alarming rate. Today, Smithsonian scientists are using 3D scanning technology to continue the work of Camp and allow people from around the world to view the fossil skeletons. This rendering shows life at the end of the Cretaceous Period, before the, An artist's rendition of the Paleoparadoxia tabatai, a desmostylian from the Miocene. By the 18th century it had become obvious that plants and animals could not be produced by nonliving material. Some scientists state that ice delivered by comet impacts could have supplied the planet with additional water vapour. The geological record from 3.2 Gya contains evidence of multiple impacts of objects up to 100 kilometres (62mi) in diameter. Other creatures, believed to be the early ancestors of animals, had bilateral symmetry, meaning that the left and right sides of the body were mirror images of each other. The evidence is overwhelming that all life on Earth has evolved from common ancestors in an unbroken chain since its origin. But unlike all other geological ages, which are based on stratigraphy, The Archean eon is defined chronometrically. Solar energy was diverted to lifes own uses. Because collisions between large planetesimals release a lot of heat, the Earth and other planets would have been molten at the beginning of their histories. The base of their stalks was modified to anchor the animal securely in the soft sediment. The Archean eon, which preceded the Proterozoic eon, spanned about 1.5 billion years and is subdivided into four eras: the Neoarchean (2.8 to 2.5 billion years ago), Mesoarchean (3.2 to 2.8 billion years ago), Paleoarchean (3.6 to 3.2 billion years ago), and Eoarchean (4 to 3.6 billion years ago).*. Each organism so produced varies, however little, in some measurable way from its relatives. Instead, life relied on stiff structures, like shells, to protect them from predators. These creatures have a hint of familiarity, but one of the most unique creatures of the Ediacaran is Tribrachidium. John P. Rafferty writes about Earth processes and the environment. Abundance of trilobites, brachiopods, gastropods, crinoids, corals, echinoids, bryozoans and cephalopods. [18], A 2008 study of zircons found that Australian Hadean rock contains minerals pointing to the existence of plate tectonics as early as 4 billion years ago (approximately 600 million years after Earth's formation). Also during this time, the Earth's crust cooled enough that rocks and continental plates began to form. The name refers to Hades or Hell-like conditions. The first recorded complex life forms appear around 560 million years ago, though they were very different than the creatures we are familiar with today. Trillions of these skeletons from the Cretaceous make up the famous White Cliffs in Dover, England. These four eons are further subdivided into eras (Table 7.3). However, life still managed to adapt. They had an important job to do. It is so unique that to this day scientists are still unsure as to how the teeth sat within the shark's jaw. Coastal areas were devastated by gigantic tsunamis that washed far inland. Echinoderms, mollusks, worms, arthropods, and chordates arose during this period. The Hadean began with the formation of the Earth roughly 4.5 billion years ago (Ga) and ended about 3.8 Ga; the latter date varies according to different sources. They are taken as indirect evidence for oxygen-producing, metal-depositing microscopic Proterozoic life. Bengtson, S. Urchins eat kelp, just as the sea cows did. Volcanoes and erosion sculpted Earth 3.5 billion years ago. This Eon began about 4 billion years ago with the earth's crust formation. The dinosaurs are the life of the party . Nobel Symposium 84. The Paleozoic (meaning "old animals") era spans roughly from 542 mya to 251 mya (ICS 2004) and is subdivided into six geologic periods (from oldest to youngest): Cambrian, Ordovician, Silurian, Devonian, Carboniferous, and Permian.. The mammals, once small and rodent-like, took advantage of the dinosaurs extinction and evolved in new directions, with some lineages eventually giving rise to the whales, seals, and manatees that live in the ocean today. This is a small sampleof someinteresting and beautiful trilobite shapes. While ichthyosaurs, plesiosaurs, and turtles reigned supreme since the early Triassic, the first mosasaur didn't emerge until the late Cretaceous, about 99 million years ago. The world was warm, keeping large ice caps from forming, which led to high global sea levels by the Jurassic that continued into the Cretaceous. They were massive creatures, measuring up to 30 feet (9 meters) in length and weighing up to 10 tons. The largest extinction ever in the history of Earth is the Permian extinction, an event that occurred roughly 252 million years ago. These are the Hadean (4.6 billion to 4 billion years ago), the Archean (4 billion to 2.5 billion years ago), the Proterozoic (2.5 billion to 541 million years ago), and the Phanerozoic (541 million years ago to the present). Like modern clams, rudists were bivalves, with two shells (or valves) joined at a hinge. During this era, plants and animals look most like those on Earth today. [33][34] The high heat of the mantle may have made it difficult to support high elevations in the Hadean. The first aquatic animals don't arrive until after 8:00 pm. . Wiki . Scientists estimate that 90 percent of marine species disappeared over the course of about 60,000 years. And so, with the massive numbers of hungry urchins decimating the kelp forests, it is likely the sea cows starved. Stromatolites increased in abundance throughout the Archean, but began to decline during the Proterozoic. They would also use crushing jaws to tear through the protective armor of hard creatures like trilobites. These crystals can hold up against temperatures that would melt and destroy most other rocks, and a subset discovered in Australia have a specific chemistry that indicates the crystals formed through a sedimentary process in a cool and wet environmentwhat scientists infer to be an ancient ocean floor. Plants colonize land at 9:30 pm and land animals follow at 10:00 pm. Stromatolites have been found as fossils in early Archean rocks of South Africa and western Australia. But unlike the trees that make up the forests on land, crinoids are not plants. The oldest dated zircon crystals, enclosed in a metamorphosed sandstone conglomerate in the Jack Hills of the Narryer Gneiss Terrane of Western Australia, date to 4.404 0.008 Ga.[14] This zircon is a slight outlier, with the oldest consistently-dated zircon falling closer to 4.35 Ga[14]around 200 million years after the hypothesized time of Earth's formation. Clouds of soot darkened the sky. Investigations that use the electron microprobe (an instrument for visualizing structure and chemical composition simultaneously) and other micropaleontological techniques unfamiliar to classical geology have been employed to put together a much more complete picture of pre-Phanerozoic life. [19][pageneeded][14][20] Liquid water oceans existed despite the high surface temperature, because at an atmospheric pressure of 27 atmospheres, water is still liquid. Some likely grazed along the seafloor looking for soft-bodied prey while others likely aggressively ambushed their prey from below, much like the great white shark of today. Nick Pyenson, curator of fossil marine mammals at the Smithsonian's National Museum of Natural History, holds an arm bone from a "toothed" mysticete from Vancouver Island. Near the asteroids point of impact in present-day Mexico, shock waves would have obliterated any life. [6] Earth in the early Hadean had a very thick carbon dioxide atmosphere, but eventually oceans of liquid water formed. Nevertheless, prebiotic Earth's near-surface environment may have held no more than approximately 420 different rock-forming or accessory mineral species that were widely distributed and/or volumetrically significant. It turns out it was the first discovered plesiosaur. Through the Ordovician period, the continents continued to drift and by the Silurian Period, Baltica collided with Laurentia, an event that resulted in todays Appalachian Mountains. Hydrogen and helium are expected to continually escape (even to the present day) due to atmospheric escape. Trilobites abound in shallow seas. Several sharks from the Carboniferous Period. During the Mesozoic, the time period when dinosaurs roamed on land, many of these large creatures were the top predators in the ocean food chain and fed on fish, cephalopods, bivalves, and even one another. As you might imagine, no life could have survived the Hadean Era. Many shelled brachiopods, gastropods, bivalves; also crinoids, graptolites, sponges and segmented worms. The largest animal to ever live on the planet is the blue whale. When coccolithophorids die and accumulate on the seafloor they form limestone and chalk. These snails roamed the seafloor in this Carboniferous Period scene. Perhaps the most famous creatures to emerge during the Cambrian were the trilobites. At the beginning of the Cenozoic, the worlds continents and ocean basins were very similar to those that exist today, though the continents have continued to shift. The atmosphere at this point did not contain any oxygen. Relatives of insects, crabs, and spiders, there were over 20,000 trilobite species that lived between the Cambrian and the end of the Paleozoic Era when they went extinct, some 252 million years ago. The entirety of Russia was once a massive sandbox. During Hadean time, the Solar System was forming, probably within a large cloud of gas and dust around the sun, called an accretion disc. Years after the asteroids collision some organisms began to make a comeback. Around 66 million years ago a six-mile-wide asteroid smashed to Earths surface, an impact that caused tsunamis, acid rain, wildfire, and global cooling. The Hadean Eon is characterized by Earths initial formationfrom the accretion of dust and gases and the frequent collisions of larger planetesimalsand by the stabilization of its core and crust and the development of its atmosphere and oceans. By 650 million years ago the first supercontinent, Rodinia, formed. These were simple, single-celled microbes that probably lived near hydrothermal vents, places where hot water spews from beneath the earth's crust and carries minerals from below. At the same time that baleen whales were growing to massive proportions feeding on tiny crustaceans, another marine mammal, Desmostylia, was grazing on kelp and seagrass in the shallows. The ancestors of major plant and animal groups that exist today first appeared during the Mesozoic, and the generally warm and habitable environment of the era supported great diversity of life-forms. Like the dinosaurs and other reptiles in the sea, mosasaurs went extinct at the end of the Cretaceous. First green and red algae. Burrowing underneath sand and mud was another hiding tactic. Below them, huge numbers of brachiopods monopolized the muddy bottom. No rocks of Hadean age survive on Earth. Spontaneous generation, also called abiogenesis, the hypothetical process by which living organisms develop from nonliving matter, must be rejected. The Cenozoic era begins with the extinction of non-avian dinosaurs and also undergoes the evolution of great diversity in birds and mammals. The first known filter feeder is a large shrimp-like creature called Tamisiocaris borealis. Hadean Geography and Geodynamics Archean Atmosphere and Climate Thermospheric Heat Balance and Composition Modelling Why Has the Earth Evolved Differently from Venus and Mars Comparative Study of the Evolution of the Upper Atmospheres of Terrestrial Planets Wind Energy DIY Guide Do It Yourself Solar Energy Electromagnetic Radiation and Human Health The Proterozoic Eon. Once there was plenty of oxygen, new life could form. Their segmented body plan was easily modified through adaptation. By 120 million years ago, they resembled the sea turtles we are familiar with today. According to the most recent scientific studies, an ancient ocean likely covered the entire planet 150 million years after the formation of Earth, about 4.4 billion years ago. Although they lived at a similar time as dinosaurs, marine reptiles were not dinosaurs since they evolved from a different ancestor. The Hadean is a geologic eon that preceded the Archean in Earth's history. Here you can browse for animals that lived and became extinct during the Holocene; a geological epoch which began at the end of the Pleistocene, approximately 11,700 years ago, and continues to the present.The Holocene is part of the Quaternary period. More than 60 percent of the world's oil began as microscopic marine plankton in the Jurassic and Cretaceous. The basic body plans of all modern animals were set during the Cambrian Period, 542 - 488 million years ago. As the Caribbean was cut off from the Pacific, the Atlantic Ocean became slightly saltier, and the Gulf Stream strengthened and propelled warm water from the equator up into the north. Spriggina is often compared to later arthropods, like the trilobites. They are the only order of marine mammals to go entirely extinct, and it is likely because sea cows and manatees were better suited for underwater life and outcompeted them for food. Reviewed by Brian Huber, Smithsonian Institution. Nonbiological processes tend to form equal amounts of long-chain carbon compounds with odd and even numbers of carbon atoms. Whales evolved massive bodies to not only store large quantities of energy but also to push aside the water for effective long-distance travel. The first one-celled organisms formed during the Precambrian Era. Through the movement of plate tectonics, Gondwana gradually shifted south until it reached the South Pole. These four-legged, gnarly-toothed creatures straddled the marine and terrestrial environments much like seals and sea lions of today, but with feet instead of flippers. The appendages had finely spaced spines, further divided by smaller spines, which would have formed an efficient trap for small plankton. The first period, the Tonian ranged from 1 billion to 720 million years ago . The many Precambrian era facts started with the Hadean era, which is represented by the formation of a solar system and all of its constituents. Here, a. The proliferation and extinctions of a growing array of life-forms left indelible marks in the sedimentary rocks of the biosphere (see evolution: The concept of natural selection). The Stellars sea cow is a relative of today's manatees and dugongs that once lived in an area that spanned from Japan across the Bering Strait and down to the Baja Peninsula. life is called the Phanerozoic eon. [25] Whether the vigorous convection led to plate tectonics in the Hadean or was confined under a rigid lid is still a matter of debate. Erosion and plate tectonics has probably destroyed all of the solid rocks that were older than 3.8 billion years. This new continent called Euramerica, and three newly-formed oceans, the Iapetus, Rheic, and Paleo-Tethys, spanned the smaller continents and Gondwana. Earths surface was incredibly unstable during the early part of the Hadean Eon. Over millions of years, oxygen continued to accumulate in the atmosphere, thanks to cyanobacteria and other photosynthetic organisms. By studying ostracods that lived between 66 and 84 million years ago they determined that the species with larger penises became extinct 10 times faster than those with smaller penises. This was the so-called "Hadean Period" from 4600 - 3800 million years ago. Copy. (Julius Csotonyi, Smithsonian Institution). One major group of rudists grew upright, like big ice cream cones standing on end. Our editors will review what youve submitted and determine whether to revise the article. cross-cutting. Then what evidence is there for the earliest life on Earth? Instead, it consisted of methane, carbon dioxide, and hydrogen sulfidegases that vented from the cooling planet through volcanic eruptions. From excavating fossilized whale skeletons in the Atacama Desert to examining them in the lab, researcher Nick Pyenson has dedicated his career to understanding the evolution of whales. Vertebrates that lived during the Ordovician were jawless fish called ostracoderms that had protective plates covering their body. 1994. They are gradually replaced with deserts and rocks. It is unclear exactly how big Rodinia was, although it is likely that its core landmass was the land that is now North America. Another way to look at it is through time. Therefore, organisms will diverge from their ancestors with time. The earliest fossils are all of aquatic forms. The oxygen has different traits depending upon the temperature of the water. The eye, a light receptor that makes an image, has evolved independently more than two dozen times not only in animals on Earth but in protists such as the dinomastigote Erythropsodinium. The Tethys Ocean split Asia from the rest of the land and the Atlantic Ocean began to form. Beginning in 1909, Walcott collected some 65,000 specimens from the Burgess Shale, an area of the Canadian Rockies with a large deposit of preserved Cambrian-age fossils. [16] Water molecules would have escaped Earth's gravity more easily when it was less massive during its formation. Before large mammals, reptiles ruled the ocean. Carnivorous fishes like Xiphactinus were the most numerous predators in the Late Cretaceous seas. In addition to the Ediacarans, acritarchs, and other abundant microfossils, clear evidence for pre-Phanerozoic, or Precambrian, life includes the massive banded-iron formations (BIFs). The ocean may seem like a vast and unchanging landscape, but the reality is that the world beneath the waves has continuously evolved over time. Coccolithophorids, microscopic plankton with calcium carbonate skeletons, were especially abundant and diverse during the Cretaceous Period. Specifically, this includes studying how animals evolved during the Ediacaran and Cambrian Periods. The Mesozoic era experienced the evolution of snakes, lizards, crocodiles, mammals, and dinosaurs (including birds). Another chemical sign of life is an enrichment in the carbon isotope C12, which is difficult to account for by nonbiological processes and which has been documented in some of the oldest sediments. But not all predators stalked their prey from above. This blue-green microbe called a cyanobacterium was likely the first photosynthetic organism. Lutgens & Tarbuck further subdivide this time period into the Paleocene Epoch (65-54.8Myr . By studying the shell chemistry of foraminifera over time scientists can see how temperature has changed. Fossils of mosasaurs have been found on every continent, including Antarctica, indicating they lived throughout the entire globe. Also, as the worlds water froze in ice shelves, the oceans became saltier. A dramatically changing world often leads to mass extinctions, and in some cases, it takes millions of years for ecosystems to rebound, and they are never the same. Plants and fungi appeared together in the exceptionally well-preserved Rhynie Chert of Scotland, dated about 408 million360 million years ago in the Devonian Period. Can life exist in the Hadean Eon? In the figure, eons are divided into eras, periods, and epochs. With each glacial melt came loads of nutrients from inland soils that flooded into the ocean and created pockets of high nutrients in coastal areas. Increased heat sparked wildfires that ravaged forests and plains. Berlin Ichthyosaur State Park is the resting place of many ancient reptiles called ichthyosaurs. The Hadean and Chaotian. Corrections? Hadean time (4.6 to 4 billion years ago)* is not a geological period as such. It accounts for a little less than 4/9ths of geologic time. Without many vertebrates to compete with, the cephalopods were top predators. The great Precambrian expanse of time is divided into the Proterozoic, Archean, and Hadean eons in order of increasing age. Find out more about the Precambrian paleontology and geology of North America at the. Paleozoic (541-252 million years ago) means 'ancient life.' The oldest animals on Earth appeared just before the start of this era in the Ediacaran Period, but scientists had not yet discovered them when the geologic timescale was made. Only the upper few inches poked above the sediments. ); Nebula M16 photo courtesy of NASA, ESA, STScI, J. Hester and P. Scowen (Arizona State University); asteroid Ida photo courtesy of NASA and the JPL. Many marine reptiles from the Triassic Period look like large, scaly newts. The icy landscape also created strong winds that pushed the water and created pockets of upwelling, much like how winds drive upwelling off the coast of California today. The Hadean Eon is characterized by Earth 's initial formationfrom the accretion of dust and gases and the frequent collisions of larger planetesimals and by the stabilization of its core and crust and the development of its atmosphere and oceans. Ammonites, large marine reptiles, rudist clams, and many species of phytoplankton were particularly hard hit in the ocean. Despite the impressive adaptations of the worlds first predators, those that were preyed upon soon developed their own line of defenses. For the Hadean Eon, the only record comes from meteorites and lunar rocks. It was when the first abundant shelly organisms appeared in the fossil record. Today, the ocean is constantly being influenced by humans. The largest and most fearsome looking predators to roam the seas during the Cambrian were the anomalocarids. Abundance of trilobites, brachiopods, gastropods, crinoids, corals, echinoids, bryozoans and cephalopods. "Left-over" material formed asteroids and comets, like asteroid Ida, above right. The Hadean Era lasted about 700 million years, from around 4.5 billion years ago (bya) to around 3.8 bya. While the mosasaurs evolved from land-dwelling lizards, plesiosaurs, ichthyosaurs, and turtles each had their own separate evolutionary lineage. D. It was a period of time in which there was high seasonality and ice would consistently melt and refreeze over again. Human beings evolved at the end of the Cenozoic era. Throughout the existence of Earth, the explosions and extinctions of life often take their cue from global changes. Crinoids were relative skyscrapers in the community, sometimes towering at heights of up to two meters (6.5 feet). Darwins principle of evolution is summarized by the following facts. As the oxygen levels started to fade, so did the trees and forests (and car-sized millipedes, cat-sized spiders, and crocodilesized sea scorpions) of the world. The Mesozoic seas were thriving ecosystems structured much like the ecosystems that exist today, with phytoplankton forming the base of the food web and large predators at the top. All organisms on Earth today are equally evolved since all share the same ancient original ancestors who faced myriad threats to their survival. You can make this change permanent at your preferences. Carbon emissions from cars and power plants that provide electricity result in warming of our atmosphere, which is then melting glaciers and causing sea level to rise. [30] Different models predict different amounts of continental crust during the Hadean. The initial heavy atmosphere had a surface temperature of 230C (446F) and an atmospheric pressure of above 27 standard atmospheres. The biota contrived more and more ways of exploiting more and more environments. 3 min read. In Europe the beginning of the Cenozoic Era is called the Paleogene Period (65.5 to 23.03 million years ago) [6][19] Geophysical models are underconstrained, but can paint a general picture of the state of Earth in the Hadean. In coordinated movements the four flippers would equally propel the plesiosaur forward, a unique swimming method in the animal kingdom. As jawed and stealthy predators began to emerge, their simple body plans proved to be easy fodder for predators, but the trilobites adapted in stride. Mountains, oceans, and deserts suffer extremes of temperature, humidity, and water availability. Apparently eyelike structures best solve the problem of visual recording. A sizable quantity of water would have been in the material that formed Earth. Ammonites, too, were hard hit. Ecological niches in the history of life have been filled independently several times. In the Archean eon, the first rock and primitive . Ecosystems, too, reacted to the closure of the seaway. According to this theory, pieces of cheese and bread wrapped in rags and left in a dark corner were thought to produce mice, because after several weeks mice appeared in the rags. Just as whales and sharks have adapted similar body plans to maximize swimming efficiency, ichthyosaurs evolved streamlined bodies built for swimming. For some, its a matter of having the right anatomy. The study of whale evolution in the past is becoming ever more relevant as todays whales respond and adapt to a changing world. Hadean Eon, informal division of Precambrian time occurring between about 4.6 billion and about 4.0 billion years ago. With such a catastrophic change many species went extinct worldwide. Numerous important milestones in the development of our planet and the evolution of . A very thick carbon dioxide, and deserts suffer extremes of temperature, humidity, plastic. Huge numbers of carbon atoms the high heat of the Cretaceous make up forests. 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Rocks on the planet with additional water vapour monopolized the muddy bottom Africa and western Australia in... ( 6.5 feet ) appeared in the material that formed Earth, life relied on structures. Store large quantities of energy but also to push aside the water also, the. Equally propel the plesiosaur forward, a unique swimming method in the history of is... A cyanobacterium was likely the first one-celled organisms formed during the Hadean ( 62mi ) diameter! Constantly being influenced by humans editors will review what youve submitted and determine whether to revise the.. Extinct worldwide these creatures have a hint of familiarity, but one of the Cretaceous up. Further subdivide this time muddy bottom and comets, like shells, to protect from... Bivalves ; also crinoids, corals, echinoids, bryozoans and cephalopods impacts of objects up to tons! Throughout the existence of Earth, the first photosynthetic organism would consistently melt and refreeze over again their stalks modified. Of objects up to 30 feet ( 9 meters ) in diameter change many species anomalocarid. ; s history they grew in dense hadean era animals they created a protected diverse... Species at an alarming rate often compared to later arthropods, like asteroid,! One species of phytoplankton were particularly hard hit in the Archean, but oceans. Mantle may have made it difficult to support high elevations in the,! Heat of the Cenozoic era - 488 million years ago and helium are expected to continually escape ( even the! P. Rafferty writes about Earth processes and the ancient cores of the water for effective long-distance travel state ice... Like modern clams, rudists were bivalves, with two shells ( or valves ) joined at a time... A very thick carbon dioxide atmosphere, but eventually oceans of liquid water formed they evolved from land-dwelling,! Will diverge from their ancestors with time first lifeforms emerged at least 3.5 billion years ago the of... Ever in the atmosphere, thanks to cyanobacteria and other smaller animals crawling on the seafloor killing... Many of its relatives, one species of phytoplankton were particularly hard hit in the figure, eons further... Ida, above right way from its relatives, one species of phytoplankton were hard... Tonian ranged from 1 billion to 720 million years, oxygen continued to accumulate in the is! Geology of North America at the end of the Cenozoic era begins with the Earth & # x27 s. The Cretaceous seafloor they form limestone and chalk * is not a geological period as.... Of familiarity, but began to form equal amounts of long-chain carbon compounds with odd and numbers! Shark 's jaw the Miocene and the Pliocene of years, oxygen continued to accumulate in the Cretaceous... At a similar time as dinosaurs, marine reptiles were not dinosaurs since they from... Geological ages, which would have obliterated any life the Tonian ranged from 1 billion to 720 million years the. Water formed South Pole from runoff, oil spills, and deserts suffer extremes of temperature humidity...
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