What are the periods of the paleozoic era. Oct 6, 2023 · Cambrian Period, earliest time divisio...

The time scale is divided into four large periods of time—the Cenozoi

Geologic Time Scale: The geologic time scale relates the age of the Earth and its history. It's divided into several eras, beginning with the Hadean era of 4600 to 4000 million years ago through the Cenozoic era that includes 65.5 million years ago to the present.The force of its movement pressed the floor of a Paleozoic sea deep into the earth's mantle, where, in effect, it melted. ... in the era of climate change, has been dubbed "white gold." Like ...... Period, Paleozoic Era, Phanerozoic Eon [485 Myr - 444 Myr ]. The Ordovician and Cambrian Periods are referred to as the "age of invertebrates", with ...After the Cambrian Explosion, the Paleozoic was rather uneventful for the next 50 million years or so. According to a USGS website, which also informs any later explanation of the Paleozoic’s periods, the Cambrian Period is recognized by the formation of the supercontinent of Gondwana. During the Cambrian, North America was located near the ...The Permian Period. The Great Dying was the worst mass extinction the Earth has ever seen. This mass extinction killed 90% of all species on Earth, including 96% of those in the oceans and 70% of those on land. Scientists are unsure what exactly caused this mass extinction, but it seems to be some combination of acid rain caused by volcanic ...Broad Geological History of the Early Paleozoic. The early Paleozoic Begins with gradual marine transgressions of the low-lying interior regions of the continents. The seas gradually regressed in conjunction with the major orogenic event known as the Caledonian orogeny. Position of the Earth's equator during the Cambrian period.The Ordovician ( / ɔːrdəˈvɪʃi.ən, - doʊ -, - ˈvɪʃən / or-də-VISH-ee-ən, -⁠doh-, -⁠VISH-ən) [9] is a geologic period and system, the second of six periods of the Paleozoic Era. The Ordovician spans 41.6 million years from the end of the Cambrian Period 485.4 million years ago (Mya) to the start of the Silurian Period 443.8 Mya ...The Paleozoic (IPA: /ˌpæli.əˈzoʊ.ɪk,-i.oʊ-, ˌpeɪ-/ PAL-ee-ə-ZOH-ik, -⁠ee-oh-, PAY-; or Palaeozoic) Era is the first of three geological eras of the Phanerozoic Eon. Beginning 538.8 million years ago (Ma), it succeeds the Neoproterozoic (the last era of the Proterozoic Eon) and ends 251.9 Ma at the start of the Mesozoic Era. [2] Series: Geologic Time—Major Divisions and NPS Fossils. The National Park System contains a magnificent record of geologic time because rocks from each period of the geologic time scale are preserved in park landscapes. The geologic time scale is divided into four large periods of time—the Cenozoic Era, Mesozoic Era, Paleozoic Era, and The ...The Paleozoic Era is divided into six periods, depending on various features like tectonic and geological environment, evolution of flora and fauna, climate, marine regressions and transgressions, etc. Refer to the following image to understand the timeline of this era, depending on the variation of characteristics across the periods. The era is usually broken down even further to six main periods: Cambrian: 542 to 488.3 million years ago Ordovician: 488.3 to 443.7 million years ago Silurian: 443.7 to 416 …Introduction Encyclopædia Britannica, Inc. The Paleozoic Era was a major interval of geologic time. It began 541 million years ago with a rapid expansion of life-forms and ended 252 million years ago with the largest mass extinction in Earth's history.Paleozoic Era, major interval of geologic time that began 538.8 million years ago with the Cambrian explosion, an extraordinary diversification of marine animals, and ended about 252 million years ago with the end-Permian extinction, the greatest extinction event in Earth history. The majorThe Paleozoic Era lasted around 289 million years and is broken into six smaller periods of time. The Paleozoic era major events began with the Cambrian Explosion, a very short period of time ...The Ordovician (/ ɔːr d ə ˈ v ɪ ʃ i. ə n,-d oʊ-,-ˈ v ɪ ʃ ən / or-də-VISH-ee-ən, -⁠doh-, -⁠ VISH-ən) is a geologic period and system, the second of six periods of the Paleozoic Era. The Ordovician spans 41.6 million years from the end of the Cambrian Period 485.4 million years ago (Mya) to the start of the Silurian Period 443. ... The Paleozoic era is also known as the era of ancient life on the planet earth. It is categorized into six different periods as Cambrian, Ordovician, Silurian, Devonian, and Carboniferous and Permian period. The Cambrian period existed about 520 to 505 million yrs ago and in that period invertebrate phyla and some invertebrate …Paleozoic Era 542 to 151 million years ago. This is the era in which much change had occurred. The first hard parts species started to appear such as primitive fish, coral, plant life, Vertebrate animals form along with arachnids, and wingless insects. During the end of the Paleozoic Era, the Permian Period begins.The Paleozoic Era is a time period in Earth's history that lasted from 541 to 252 million years ago. It is divided into six periods: the Cambrian, Ordovician, Silurian, Devonian, Carboniferous, and Permian. The Cambrian Period was the first period of the Paleozoic Era. It lasted from 541 to 488 million years ago.The Paleozoic Era is further divided in to seven periods/sub-periods: the Cambrian, the Ordovician, the Silurian, the Devonian, the Mississippian, the …The Paleozoic comes after the Neoproterozoic Era of the Proterozoic Eon and is followed by the Mesozoic Era. The Paleozoic was a time of dramatic geological, climatic, and evolutionary change. The Cambrian witnessed the most rapid and widespread diversification of life in Earth's history, known as the Cambrian explosion , in which most modern ...Answers for Last period of the Paleozoic era (7) crossword clue, 7 letters. Search for crossword clues found in the Daily Celebrity, NY Times, Daily Mirror, Telegraph and major publications. Find clues for Last period of the Paleozoic era (7) or most any crossword answer or clues for crossword answers.Carboniferous Period, fifth interval of the Paleozoic Era, succeeding the Devonian Period and preceding the Permian Period. In terms of absolute time, the Carboniferous Period began approximately 358.9 million years ago and ended 298.9 million years ago.This first major flowering of multicellular eukaryotes (organisms with neucleated cells), which is known as the Cambrian explosion, marks the onset of the Cambrian period—the first period of the first era (the Paleozoic) of the Phanerozoic eon (Mayr 2001). The Phanerozoic eon is divided into three eras: The Paleozoic, Mesozoic, and Cenozoic ...The geologic time scale or geological time scale ( GTS) is a representation of time based on the rock record of Earth. It is a system of chronological dating that uses chronostratigraphy (the process of relating strata to time) and geochronology (a scientific branch of geology that aims to determine the age of rocks). The Permian period lasted from 299 to 251 million years ago* and was the last period of the Paleozoic Era. The distinction between the Paleozoic and the Mesozoic is made at the end of the Permian in recognition of the largest mass extinction recorded in the history of life on Earth. It affected many groups of organisms in many different ...The Paleozoic lasted for nearly 290 million years… from 541 to 252 million years ago. ... Trilobites served to neatly bookend the Paleozoic, arising in the Lower ...Life During the Paleozoic. The Paleozoic Era is literally the era of “old life.”. It lasted from 544 to 245 million years ago and is divided into six periods. Major events in each period of the Paleozoic Era are described in Figure below. The era began with a spectacular burst of new life.Oct 6, 2023 · Cambrian Period, earliest time division of the Paleozoic Era and Phanerozoic Eon, lasting from 538.8 million to 485.4 million years ago. The Cambrian System, named by English geologist Adam Sedgwick for slaty rocks in southern Wales and southwestern England, contains the earliest record of abundant and varied life-forms. The Paleozoic Era follows the Precambrian Eon and precedes the Mesozoic Era. The term Paleozoic is used to describe the age of rocks that formed and accumulated in that time period. Highlights include: • Dominant large animals: Invertebrates dominate early; fish and amphibians appear in the middle Paleozoic, and reptiles appear even …The Paleozoic Era came before the Mesozoic. The Paleozoic Era was comprised of six periods. The Cambrian period introduced developing arthropods and invertebrate animals with an exoskeleton, such as insects, crustaceans, and more. The Ordovician kickstarted the development of straight-shelled mollusks, distant relatives of …Carnotaurus was a sauropod of spectacular proportions. Learn more about the Carnotaurus, Early Cretaceous dinosaurs, and dinosaurs of all eras. Advertisement CARNOTAURUS (CAR-noh-TORE-us) Period: Early Cretaceous Advertisement Order, Subord...The geologic time scale is divided into four large periods of time—the Cenozoic Era, Mesozoic Era, Paleozoic Era, and The Precambrian. Article 1: Cenozoic Era. The Cenozoic Era (66 million years ago [MYA] through today) is the "Age of Mammals." North America’s characteristic landscapes began to develop during the Cenozoic.The Paleozoic era is divided into six geologic periods and is the longest era lasting from 541 to 251.902 million years ago. The Paleozoic era can be defined as a dramatic geological, evolutionary, and climatic change. The six geologic periods are Cambrian period, Ordovician period, Silurian period, Devonian period, Carboniferous …Life During the Paleozoic. The Paleozoic Era is literally the era of “old life.”. It lasted from 544 to 245 million years ago and is divided into six periods. Major events in each period of the Paleozoic Era are described in Figure below. The era began with a spectacular burst of new life. Railroads struggled during the Great Depression, as did the rest of the nation. Read about railroads of the Depression era and the New Deal. Advertisement The period between 1930 and 1945 was a time of contrast and change. The railroad indu...The Paleozoic Era is divided into the Cambrian, Ordovician, Silurian, Devonian, and Carboniferous periods, each with characteristic groups of fossils.The Paleozoic Era, meaning 'Ancient Life' in Greek, stretched from 542- 251 Ma, and can be characterized as a time when the Earth was teeming with aquatic ...Ordovician Period. The Cambrian* Period begins the Phanerozoic Eon, the last 542 million years during which fossils with hard parts have existed. It is the first division of the Paleozoic Era (542Ma -251Ma). Marine animals with mineralized skeletons make their first appearance in the shallow seas of the Cambrian, though only "small shelly ...Permian Period, in geologic time, the last period of the Paleozoic Era, lasting from 298.9 million to 252.2 million years ago. The climate was warming throughout Permian times, and, by the end of the period, hot and dry conditions were so extensive that they caused a crisis in Permian marine and terrestrial life.The era is usually broken down even further to six main periods: Cambrian: 542 to 488.3 million years ago Ordovician: 488.3 to 443.7 million years ago Silurian: 443.7 to 416 …List the 7 periods of the Paleozoic Era in order, spelled correctly, from oldest to youngest:, 3. What is the Carboniferous? and more. Study with Quizlet and memorize flashcards containing terms like 1. When did the Paleozoic Era begin and end? (Give actual dates from Geologic time Scale), 2. List the 7 periods of the Paleozoic Era in order ...Trilobite Family Diversity over the Paleozoic Era. Although trilobites are the signature organism of the Paleozoic, first appearing in the Early Cambrian, their peak diversity was in the early Paleozoic, and they began a general decline in the upper Paleozoic (despite bursts of adaptive radiations in the Ordovician, Silurian, and Devonian periods), and that ended with their extinction in the ... The Paleozoic Era spanned six geological periods, a time span reaching from about 541 million years ago to about 252.17 million years ago, the longest era ...The Permian ( / ˈpɜːrmi.ən / PUR-mee-ən) [4] is a geologic period and stratigraphic system which spans 47 million years from the end of the Carboniferous Period 298.9 million years ago (Mya), to the beginning of the Triassic Period 251.902 Mya. It is the last period of the Paleozoic Era; the following Triassic Period belongs to the ... Feb 1, 2021 · The temperature of a planet is linked with the diversity of life that it can support. MIT geologists have now reconstructed a timeline of the Earth’s temperature during the early Paleozoic era, between 510 and 440 million years ago — a pivotal period when animals became abundant in a previously microbe-dominated world. 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 start of the Paleozoic era, between roughly 542 mya and 530 mya, is a time when a large number of body …In subsequent periods of the Paleozoic Era, invertebrates such as octopuses, shelled mollusks, corals and starfish evolved, along with the first fish, amphibians and reptiles. By about 430 mya, during the Silurian Period, the first plants and animals moved onto land and became established.It’s easy to get distracted by the abundance and diversity of life that appears and flourishes during the Paleozoic. But life and evolution are influenced by the geologic processes that are always shaping the earth’s environments. The Paleozoic saw periods of intense mountain building, extensive glaciations, widespread shallow seas, and the ...The era is usually broken down even further to six main periods: Cambrian: 542 to 488.3 million years ago Ordovician: 488.3 to 443.7 million years ago Silurian: 443.7 to 416 …The Paleozoic era is followed by the Mesozoic and Cenozoic eras. The Paleozoic era comprises from oldest to youngest the following six geologic periods: Cambrian, Ordovician, Silurian, Devonian, Carboniferous, and Permian. During the nearly 300 million years of the Paleozoic era, the fossil evidence records dramatic shifts in the forms of life ...Periods. Just as eons are subdivided into eras, eras are subdivided into units of time called periods. The most well known of all geological periods is the Jurassic period of the Mesozoic era (the movie Jurassic Park, of course, has something to do with that). The Paleozoic era is divided into six periods.Progressing from the oldest to the current, the four major eras of Earth’s geological history are Precambrian, Paleozoic, Mesozoic and Cenozoic. The current GTS era, the Cenozoic Era, began 65.5 million years ago.The Devonian Period occurred from 419.2 million to 358.9 million years ago. It was the fourth period of the Paleozoic Era. It was preceded by the Silurian Period and followed by the Carboniferous ...It is the oldest and longest era of the Phanerozoic Eon. The era is usually broken down even further to six main periods: Cambrian: 542 to 488.3 million years ago. Ordovician: 488.3 to 443.7 ...Carboniferous Period, fifth interval of the Paleozoic Era, succeeding the Devonian Period and preceding the Permian Period. In terms of absolute time, the Carboniferous Period began approximately 358.9 million years ago and ended 298.9 million years ago.It is divided into six periods: the Cambrian, Ordovician, Silurian, Devonian, Carboniferous, and Permian. The Cambrian Period was the first period of the …The Paleozoic Era, one of the longest of the Eras, is the oldest Era which started approximately 541 million years ago and ended about 252 million years ago. Its name means “ancient life” in Greek and it is known for the variety of life that rapidly began to appear. The Paleozoic Era can be subdivided into six geologic periods. 12 jui. 2006 ... The Paleozoic era occurred 542–251 million years ago, and marks the spread of life on earth. It takes in the Cambrian, Ordovician, Silurian, ...The Phanerozoic Eon is a period of geological history that spans 542 million years and is typically subdivided into three eras. These eras are: Paleozoic Era: 542 to 251 million years ago ...The Paleozoic Era. 543 to 248 Million Years Ago. The Paleozoic is bracketed by two of the most important events in the history of animal life. At its beginning, multicelled animals underwent a dramatic "explosion" in diversity, and almost all living animal phyla appeared within a few millions of years. At the other end of the Paleozoic, the ...The Cambrian Period is part of the Paleozoic Era. The International Subcommittee on Cambrian Stratigraphy maintains a page with lots of technical information on the Cambrian. You can also take a look at the University of Calgary's exhibit on the Burgess Shale , in present-day British Columbia, a Middle Cambrian site known for its excellent ...The Phanerozoic Eon is a period of geological history that spans 542 million years and is typically subdivided into three eras. These eras are: Paleozoic Era: 542 to 251 million years ago. Mesozoic Era: 251 to 65 million years ago. Cenozoic Era: 65 million years ago to present. Mesozoic. The dinosaurs and the mammals appeared during the ...The Paleozoic (or Palaeozoic) Era is the earliest of three geologic eras of the Phanerozoic Eon, spanning from roughly 541 to 252. 2 million years ago (ICS, 2004). It is the longest of the Phanerozoic eras, and is subdivided into six geologic periods (from oldest to least old): the Cambrian, Ordovician, Silurian, Devonian, Carboniferous, and ...This first major flowering of multicellular eukaryotes (organisms with neucleated cells), which is known as the Cambrian explosion, marks the onset of the Cambrian period—the first period of the first era (the Paleozoic) of the Phanerozoic eon (Mayr 2001). The Phanerozoic eon is divided into three eras: The Paleozoic, Mesozoic, and Cenozoic ...The Paleozoic Era began with the Cambrian Explosion, a relatively rapid period of speciation that kicked off a long period of life flourishing on Earth. Vast …Paleozoic Era; The word “Palaeozoic” comes from two Greek words meaning “ancient” and “life”. It was chosen as the name for this era because the rocks formed at this time are the first in which easily identified fossils appear. The Palaeozoic Era lasted at least 300,000,000 years and is divided into six separate periods.The Carboniferous Period lasted from about 359.2 to 299 million years ago* during the late Paleozoic Era. permian Period The Permian is a geologic period and system which spans 46.7 million years from the end of the Carboniferous Period 298.9 million years ago, to the beginning of the Triassic period 251.902 Mya.The Paleozoic Era. The Paleozoic Era occurred from about 541 million years ago to about 252 million years ago. The meaning of the word Paleozoic derives from the Greek Word palaios – which means “ancient” …The Paleozoic Era is the first of three geological eras of the Phanerozoic Eon. Beginning 538.8 million years ago , it succeeds the Neoproterozoic and ends 251.9 Ma at the start of the Mesozoic Era. The Paleozoic is subdivided into six geologic periods :It’s easy to get distracted by the abundance and diversity of life that appears and flourishes during the Paleozoic. But life and evolution are influenced by the geologic processes that are always shaping the earth’s environments. The Paleozoic saw periods of intense mountain building, extensive glaciations, widespread shallow seas, and the ...Era Period and epoch ... During the Paleozoic Era, there were times when there was only a single global continent (Pangea), but landmasses joined and separated with the passage of time. The global map was significantly different during the Mesozoic, with major masses (Gondwanaland and Laurasia) during the Paleozoic and Mesozoic Eras. ...The Phanerozoic is divided into three eras largely on the basis of the types of living things that arose or dominated in each. They are the Paleozoic, Mesozoic, and Cenozoic eras. Paleozoic Era. The Paleozoic Era began and ended with two extraordinary events. The Cambrian explosion, a rapid and wide diversification of multicellular life-forms ...Prehistoric clip art bundleThis set includes the Paleozoic Era, the Mesozoic Era, and the Cenozoic Era.I will be adding the Precambrian Era and will probably be breaking that up into the 3 sections. I will also be adding another set to this bundle of 12 additional dinosaurs within the next few weeks.All images are color and black and white and are 300 dpi .The Phanerozoic Eon covers 541 million years and includes three major geological eras: the Paleozoic, Mesozoic and, Cenozoic. Three definitions for Eon are: 1. An indefinitely long period of time ...The earliest Paleozoic had a significant biological explosion and contains evidence of a wide variety of evolutionary paths, including the evolutionary invention of hard parts like shells, spikes, teeth, and scales. Paleontologists refer to this event as the Cambrian Explosion, named after the first period in the Paleozoic. Scientists debate ...The Ordovician ( / ɔːrdəˈvɪʃi.ən, - doʊ -, - ˈvɪʃən / or-də-VISH-ee-ən, -⁠doh-, -⁠VISH-ən) [9] is a geologic period and system, the second of six periods of the Paleozoic Era. The Ordovician spans 41.6 million years from the end of the Cambrian Period 485.4 million years ago (Mya) to the start of the Silurian Period 443.8 Mya ...It is the oldest and longest era of the Phanerozoic Eon. The era is usually broken down even further to six main periods: Cambrian: 542 to 488.3 million years ago. Ordovician: 488.3 to 443.7 ... Study with Quizlet and memorize flashcards containing terms like 1. When did the Paleozoic Era begin and end? (Give actual dates from Geologic time Scale), 2. List the 7 periods of the Paleozoic Era in order, spelled correctly, from oldest to youngest:, 3.The Permian ( / ˈpɜːrmi.ən / PUR-mee-ən) [4] is a geologic period and stratigraphic system which spans 47 million years from the end of the Carboniferous Period 298.9 million years ago (Mya), to the beginning of the Triassic Period 251.902 Mya. It is the last period of the Paleozoic Era; the following Triassic Period belongs to the ...Oct 6, 2023 · Cambrian Period, earliest time division of the Paleozoic Era and Phanerozoic Eon, lasting from 538.8 million to 485.4 million years ago. The Cambrian System, named by English geologist Adam Sedgwick for slaty rocks in southern Wales and southwestern England, contains the earliest record of abundant and varied life-forms. An era is not a defined number of years. Rather, it is a period of time marked by certain characteristics, such as historical events. In geology, an era is composed of periods. According to the Encyclopedia Britannica, geological eras encom...What are the 7 periods from oldest to youngest in the Paleozoic? The major divisions of the Paleozoic Era, from oldest to youngest, are the Cambrian (541 million to 485.4 million years ago), Ordovician (485.4 million to 443.8 million years ago), Silurian (443.8 million to 419.2 million years ago), Devonian (419.2 million to 358.9 million years ...Carboniferous Period, fifth interval of the Paleozoic Era, succeeding the Devonian Period and preceding the Permian Period. In terms of absolute time, the Carboniferous Period began approximately 358.9 million years ago and ended 298.9 million years ago.Paleozoic Era. : Stratigraphy. You can find out more about the Paleozoic by clicking on the chart below! A favorite exercise in introductory paleontology courses is to invent mnemonics for the periods of the Paleozoic. These mnemonics all stand for the seven time periods into which the Paleozoic is divided: Cambrian , Ordovician, Silurian ...The Paleozoic Era is a stage of the history of the earth that occupied more than 290 million years of duration, beginning more than 540 million years ago and ending more than 250 years ago. The period begins after the disintegration of the Pannotia supercontinent, and it ends with the formation of the supercontinent Pangaea.The late Palaeozoic era spans from about 419 million years ago to 252 million years ago, and is subdivided into three geological periods in chronological order: the Devonian, Carboniferous and Permian. The late Palaeozoic is characterised by dramatic tectonic movements, global climatic changes and evolutionary novelties both in the …What are the 7 periods from oldest to youngest in the Paleozoic? The major divisions of the Paleozoic Era, from oldest to youngest, are the Cambrian (541 million to 485.4 million years ago), Ordovician (485.4 million to 443.8 million years ago), Silurian (443.8 million to 419.2 million years ago), Devonian (419.2 million to 358.9 million years ...The Paleozoic Era is divided into the Cambrian, Ordovician, Silurian, Devonian, and Carboniferous periods, each with characteristic groups of fossils. The Cambrian Period saw the explosion of new kinds of invertebrate animals in the oceans, including trilobites (Figure 2), primitive kinds of shellfish, including brachiopods and molluscs, and other groups of invertebrates that failed to survive ...The temperature of a planet is linked with the diversity of life that it can support. MIT geologists have now reconstructed a timeline of the Earth's temperature during the early Paleozoic era, between 510 and 440 million years ago — a pivotal period when animals became abundant in a previously microbe-dominated world.The Paleozoic rock layers are more than 1,500 feet thick in some places and were deposited over a span of 130 million years during the three geologic time periods known as the Cambrian, Ordovician, and Devonian (Fig. 2). The manner in which they were deposited varied through time, and is described in greater detail in two parts: This first major flowering of multicellular eukaryotes (organisms with neucleated cells), which is known as the Cambrian explosion, marks the onset of the Cambrian period—the first period of the first era (the Paleozoic) of the Phanerozoic eon (Mayr 2001). The Phanerozoic eon is divided into three eras: The Paleozoic, Mesozoic, and Cenozoic ...Arid climatic conditions led to the formation of red sediments and salt deposits. During the Permian period, there was a fundamental change in tectonics from .... Paleozoic Era. : Stratigraphy. You can find out more about Progressing from the oldest to the current, the four major e The Paleozoic is divided into six periods: the Cambrian, Ordovician, Silurian, Devonian, Carboniferous(in the U.S., this is divided into the Mississippian and Pennsylvanian Periods), and Permian. Most of these … The Ordovician* lasted about 45 million years and saw the transition f The Permian ( / ˈpɜːrmi.ən / PUR-mee-ən) [4] is a geologic period and stratigraphic system which spans 47 million years from the end of the Carboniferous Period 298.9 million years ago (Mya), to the beginning of the Triassic Period 251.902 Mya. It is the last period of the Paleozoic Era; the following Triassic Period belongs to the ...Cenozoic Era 65 mya—present Neogene Period 23 mya—present. Holocene Epoch 8000 ya—present. Pleistocene Epoch 1.8 mya—8000ya. Pliocene Epoch 5.3 mya—1.8 mya. ... Triassic Period 250 mya—200 mya Paleozoic Era 542 mya—250 mya Permian Period 300 mya—250 mya ... Carboniferous Period, fifth interval of the Paleozoic Era, succ...

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