It was at the end of the Paleozoic Era that the trilobite disappeared. For years the trilobite’s extinction had been blamed on a sudden increase in the numbers of trilobite predators. …. Other theories linked to trilobite extinction include climate change, sea-level fluctuation, and even the effects of meteorite impact.10 Oct 2023 ... This era spanned from roughly 542 million years ago to roughly 251 million years ago. The Paleozoic era is subdivided into six geologic periods: ...The date of the extinction marks the end of the Paleozoic and the beginning of the Mesozoic Era, largely accepted as 251 Mya. Studies of the Cretaceous Period have discovered several possible ways in which geology can influence life – especially negatively: 29 Most of the following discussion is based on MacDougall 2011, 188-202.10 Oct 2023 ... This era spanned from roughly 542 million years ago to roughly 251 million years ago. The Paleozoic era is subdivided into six geologic periods: ...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. Cambrian was the earliest geological period in the Paleozoic Era. It existed between 542.0 to 488.3 million years ago. The marine invertebrates such as the Trilobites species dominated this period. The climate was generally cold but continually got warm with receding glaciers.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 ...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...Quaternary Period (2.6 million years ago to present) Glaciers of the Pleistocene Epoch (2.6 million years ago to 11,700 years ago) reached northeast Kansas at least twice, leaving behind unsorted clay, sand, gravel, and boulders. Quartzite boulders, picked up by the glaciers far to the north and deposited in Kansas as the ice retreated, are ...Paleozoic Era. Era of ancient life, which began about 544 million years ago, when organisms developed hard parts, and ended with mass extinctions about 245 million years ago. Paleozoic Era. a great number of different kinds of organisms evolved; for the first time, many organisms had hard parts, including shells and outer skeletons. The Cambrian Period ( / ˈkæmbri.ən, ˈkeɪm -/ KAM-bree-ən, KAYM-; sometimes symbolized Ꞓ) is the first geological period of the Paleozoic Era, and of the Phanerozoic Eon. [5] The Cambrian lasted 53.4 million years from the end of the preceding Ediacaran Period 538.8 million years ago (mya) to the beginning of the Ordovician Period 485.4 ... The Ordovician Period: 485 to 444 million years ago What did Earth look like during the Ordovician Period?Eras of the Phanerozoic. The Phanerozoic is divided into three eras: the Paleozoic, Mesozoic, and Cenozoic, which are further subdivided into 12 periods.The Paleozoic features the rise of fish, amphibians and reptiles. The Mesozoic is ruled by the reptiles, and features the evolution of mammals, and more famously, dinosaurs, including …Aug 29, 2019 · 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 amounts of life forms from the oceans moved onto the land. Plants were the first to make the move, followed by invertebrates. Not long afterward, vertebrates took to the land. The Devonian, part of the Paleozoic era, is otherwise known as the Age of Fishes, as it spawned a remarkable variety of fish. ... By the end of the period the first ferns, horsetails, and seed ... Jan 4, 2021 · The Ordovician 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 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 ... Students complete common core objectives by researching the six periods of the Paleozoic Era in order to complete this blank outline. The six periods are, ...17 Jun 2023 ... During the Cambrian period, for example, there was a considerable increase in oxygen levels, providing the necessary conditions for a surge of ...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’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 Paleozoic Era, meaning "ancient life," spans a significant portion of Earth's geologic timescale, from around 541 million to about 252 million years ago. ... Periods of the Paleozoic Era. The Paleozoic Era is further divided into six distinct periods: Period Years Ago (Million Years) Cambrian: 541-485: Ordovician: 485-443: Silurian: 443-419:9 Jul 2014 ... The Permian Period: The Permian Period of the Paleozoic Era:299 to 251 million years ago · Ratings & Reviews · Join the discussion.The Paleozoic was the first of the three major eras of the Phanerozoic Eon; this is reflected in its name: paleozoic is derived from the Greek term for “ancient life.”. The Paleozoic is divided into six periods. From oldest to youngest, they are the Cambrian (541 million to 485 million years ago), Ordovician (485 million to 443 million ...The Paleozoic was the first of the three major eras of the Phanerozoic Eon; this is reflected in its name: paleozoic is derived from the Greek term for “ancient life.”. The Paleozoic is divided into six periods. From oldest to youngest, they are the Cambrian (541 million to 485 million years ago), Ordovician (485 million to 443 million ... The first known major mass extinction event occurred during the Ordovician Period of the Paleozoic Era on the Geologic Time Scale. At this time in the history of Earth, life was in its early stages. The first known life forms appeared about 3.6 billion years ago, but by the Ordovician Period, larger aquatic life forms had come into existence.8.6: Paleozoic. Figure 8.6.1 8.6. 1: The trilobites had a hard exoskeleton and were an early arthropod, the same group that includes modern insects, crustaceans, and arachnids. The Phanerozoic eon is the most recent eon and represents time in which fossils are common, 541 million years ago to today.Ans. The paleozoic era is the period in the Earth's history when the complex life evolved, took their initial breath of oxygen on dry land, and all the forerunners of multicellular organisms on Earth began to live. The six periods in the paleozoic era are Cambrian, Ordovician, Silirurian, Devonian, Carboniferous, and Permian.paleozoic era. The first of three geologic eras squeezed into the last 10% of Earth's whole geologic history. the part of geologic time 570-245 million years ago ;it's part of the Phanerozoic eon or "evident life" (lots of fossils) invertebrates, fishes, amphibians, reptiles, ferns, and cone-bearing trees were dominant, made os seven periods.Learn what the geologic time scale is. Identify eons, eras, periods, and epochs on the time scale, and study the history and development of the...Paleozoic era. The Paleozoic era, which happened and extended from about 542 million years ago to 251 million years ago, was a time when there were many important changes on Earth. The era began with the rupture of a super continent known as Pannotia, and the formation of a new one. Plants spread and evolved, and the first vertebrate animals ...The Silurian ( / sɪˈljʊəriːən, saɪ -/ sih-LURE-ee-ən, sy-) [8] [9] [10] is a geologic period and system spanning 24.6 million years from the end of the Ordovician Period, at 443.8 million years ago ( Mya ), to the beginning of the Devonian Period, 419.2 Mya. [11] The Silurian is the shortest period of the Paleozoic Era. Mar 13, 2018 · The Paleozoic era began around 542 million years ago with a massive explosion of life forms. It ended 291 million years later with the extinction of between 90 and 95 percent of life on the planet. Its climate was marked by massive temperature fluctuations as continental masses shifted around the Earth’s surface. ... The Paleozoic Era, which ran from about 542 million years ago to 251 million years earlier, was a time of great change on the Earth. The period started with the breakup of one supercontinent and the formation of many. Plants became extensive. And the first vertebrate animals conquered land. The Paleozoic is bracketed by two of one of the …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. This is called the Cambrian explosion. 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. Silurian Time Span. Date range: 443.8 million years ago to 419.2 million years ago. Length: 24.6 million years (0.54% of geologic time) Geologic calendar: November 26 (7 PM)–November 28 (6 PM) (1 day, 23 hours) Silurian age fossil corals, Great Basin National Park, Nevada. NPS image.The average duration of the 614 long eccentricity cycles from 0 to 249 Ma, 405.5 kyr, was used as the period for the orbital eccentricity metronome for the Paleozoic Era. The interval of 249–249.41 Ma was classified as E615 and 715 long eccentricity cycles from E615 to E1329 were constructed back in geologic time to 538.93 Ma.Oct 24, 2022 · The Paleozoic Era is one of the most important periods in Earth’s history. It is the longest era of the Phanerozoic Eon, lasting close to 200 million years. The era was characterized by major events and changes in the planet’s geology, climate, and life forms. The periods that followed the Cambrian during the Paleozoic Era are marked by further animal evolution and the emergence of many new orders, families, and species. As animal phyla continued to diversify, new species adapted to new ecological niches. During the Ordovician period, which followed the Cambrian period, plant life first appeared on land. By the beginning of the Paleozoic Era most of North America, including what is now northern Arizona, was surrounded by mostly temperate seas. Today’s western coast of North America would have been situated along the equator and oriented in an east-west direction, or rotated clockwise about 90 o from the current orientation.24 Feb 2022 ... What is Paleozoic Era? What are the periods of Paleozoic Era? · The Cambrian Period: · The Ordovician Period: · The Silurian Period: · The Devonian ...This time period took place 359 to 299 million years ago. The Carboniferous period, part of the late Paleozoic era, takes its name from large underground coal deposits that date to it. Formed from ...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.This era was between about 250 to 66 million years ago. During this period, life evolved and diversified. It gets its name from the Greek language, which means ‘Middle life.’. This period is also famous as the age of dinosaurs or the age of reptiles. The Mesozoic era existed between the Paleozoic and the Cenozoic era.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 Cambrian is the oldest period of the Paleozoic. Triassic, Jurassic, and Cretaceous are the names of the periods in the Mesozoic Era. The Mesozoic Era (251 - 65Ma) contains 3 Geological Periods ...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 names derive from locations where rocks of these ages were first studied.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 Paleozoic Era, which began more than 540 million years ago and lasted more than 160 million years, was an important time period for the evolution of life on Earth. During this era, the first fish and land plants appeared, along with the first amphibians, reptiles, and eventually reptiles that could fly.16 Oct 2017 ... The Paleozoic Era, a term that means "old animal life," is characterized by extinct animal groups such as trilobites. The Mesozoic Era ...Study with Quizlet and memorize flashcards containing terms like In class, we learned that the Paleozoic Era is the time of oldor ancient life. In order from earliest to latest, the periodsof the Paleozoic Era are: Cambrian, Ordovician, Silurian,Devonian, Carboniferous, and Permian. The CambrianPeriod was named after Cambria, the Latin name for …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 largest mass extinction in history wiped out ...Ans. The paleozoic era is the period in the Earth's history when the complex life evolved, took their initial breath of oxygen on dry land, and all the forerunners of multicellular organisms on Earth began to live. The six periods in the paleozoic era are Cambrian, Ordovician, Silirurian, Devonian, Carboniferous, and Permian.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 ...10 Oct 2023 ... This era spanned from roughly 542 million years ago to roughly 251 million years ago. The Paleozoic era is subdivided into six geologic periods: ...After the Precambrian was the Paleozoic Era (paleozoic means "early life"), and it lasted from 600 million to about 240 million years ago. The succeeding eras are the Mesozoic (middle life) and Cenozoic (recent life). Eras have been divided into smaller units of time called periods, which have been named in a different way.Viewed from space, the Paleozoic Earth would be a foreign world. During this era, seas flooded the continents and receded several times. During the early Paleozoic three small continents— Laurentia, Siberia, and Baltica—split apart from the rest of the supercontinent Gondwana and formed the Lapetus Ocean in between. 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 ...31 Jan 2018 ... The final geologic time period in the Paleozoic Era is the Permian Period (286 mya to 245 mya). The onset of the Paleozoic Era is marked by the ...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. Africa - Paleozoic, Fossils, Geology: The Paleozoic Era consists of the Cambrian, Ordovician, Silurian, Devonian, Carboniferous, and Permian periods and includes two major mountain-building episodes. The continent of Africa may be said to have taken shape during the Paleozoic. A glacial period during the Ordovician is evidenced by widespread deposition tillites, which may be seen in southern ... The Phanerozoic is divided into three eras: the Paleozoic, Mesozoic, and Cenozoic, which are further subdivided into 12 periods. Paleozoic Era. There are six periods in the Paleozoic era: Cambrian, Ordovician, Silurian, Devonian, Carboniferous and Permian. Cambrian Period. Spans from 541 to 485 million years ago.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 ...Paleozoic Era · Cambrian Period (600 to 500 million years ago) · Ordovician Period (500 to 435 million years ago) · Silurian Period (435 to 410 million years ago).Quaternary Period (2.6 million years ago to present) Glaciers of the Pleistocene Epoch (2.6 million years ago to 11,700 years ago) reached northeast Kansas at least twice, leaving behind unsorted clay, sand, gravel, and boulders. Quartzite boulders, picked up by the glaciers far to the north and deposited in Kansas as the ice retreated, are ...The Paleozoic Era, which began more than 540 million years ago and lasted more than 160 million years, was an important time period for the evolution of life on Earth. During this era, the first fish and land plants appeared, along with the first amphibians, reptiles, and eventually reptiles that could fly.This time period took place 359 to 299 million years ago. The Carboniferous period, part of the late Paleozoic era, takes its name from large underground coal deposits that date to it. Formed from ...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.7. What are the periods in the Paleozoic era? Cambrian, Ordovician, Silurian, Devonian, Mississippian, Pennsylvanian, Permian. What are the periods in the Mesozoic era? Triassic, Jurassic, Cretaceous. What are the periods in the Cenozoic era? Paleogene, Neogene, Quaternary.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 names derive from locations where rocks of these ages were first studied. Note: The Paleozoic Era is divided into periods: Cambrian, Ordovician, Silurian, Devonian, Mississippian, Pennsylvanian, and Permian. Click on the period ...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. conveniently divided into eras on the basis of life-development: thus Paleozoic (ancient life), Mesozoic (medieval life), and Cenozoic (modern life). These larger divisions or eras are furthermore sepa-rated into geologic periods, and the periods in turn into epochs. The present standard of classification has been used for nearly ninetyThe meaning of PALEOZOIC is of, relating to, originating in, or being an era of geologic history that extends from the beginning of the Cambrian to the close of the Permian and is marked by the culmination of nearly all classes of invertebrates except the insects and in the later epochs by the appearance of terrestrial plants, amphibians, and reptiles; also : …Study with Quizlet and memorize flashcards containing terms like In class, we learned that the Paleozoic Era is the time of oldor ancient life. In order from earliest to latest, the periodsof the Paleozoic Era are: Cambrian, Ordovician, Silurian,Devonian, Carboniferous, and Permian. The CambrianPeriod was named after Cambria, the Latin name for …17 Jun 2023 ... During the Cambrian period, for example, there was a considerable increase in oxygen levels, providing the necessary conditions for a surge of ...The Cambrian is the oldest period of the Paleozoic. Triassic, Jurassic, and Cretaceous are the names of the periods in the Mesozoic Era. The Mesozoic Era (251 - 65Ma) contains 3 Geological Periods ...The Paleozoic Era, which began more than 540 million years ago and lasted more than 160 million years, was an important time period for the evolution of life on Earth. During this era, the first fish and land plants appeared, along with the first amphibians, reptiles, and eventually reptiles that could fly.Aug 25, 2023 · 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 Geological time succeeding Azoic Era, was dramatic and rich in life. This period is divided into three eras. These were significant periods in earth's history. Of these, the oldest era was the Paleozoic era. It ranged from 600 to 210 million years ago. Thus its duration was nearly 390 million years.Viewed from space, the Paleozoic Earth would be a foreign world. During this era, seas flooded the continents and receded several times. During the early Paleozoic three small continents— Laurentia, Siberia, and Baltica—split apart from the rest of the supercontinent Gondwana and formed the Lapetus Ocean in between.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. This is called the Cambrian explosion.The Paleozoic Era From The Cambrian Explosion To The Permian Extinction So Much Change!. The Paleozoic Era, b oy is there a lot to unpack here! From The Cambrian Explosion to The Permian Extinction, 290 Million years of dramatic change for the earth and the life on it!. There are 6 geologic periods each with its own climate, geography, plants …The U.S. House Oversight Committee is probing a collection of period tracking apps and data brokers in light of emerging concerns about how private health data might be weaponized in the dawning post-Roe v. Wade era. The committee issued le...The Paleozoic Era, meaning "ancient life," spans a significant portion of Earth's geologic timescale, from around 541 million to about 252 million years ago. ... Periods of the Paleozoic Era. The Paleozoic Era is further divided into six distinct periods: Period Years Ago (Million Years) Cambrian: 541-485: Ordovician: 485-443: Silurian: 443-419:
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THE PALEOZOIC ERA (545-250 million years ago) This period saw the evolution of life from single celled organisms to bony fish and sharks. A rapid increase in the number of shark species occurred during this time. In an age called the Carboniferous some sharks evolved weird and crazy appendages. None of the sharks that lived in the Paleozoic are ...The Paleozoic Era spanned that period of geologic time during which the evolution of the first invertebrates, vertebrates, terrestrial (land-based) plants, bony fish, reptiles, insects, etc. took place. The end of the Paleozoic Era (approximately 245 mya) marks the largest mass extinction of species in Earth's history.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 first known major mass extinction event occurred during the Ordovician Period of the Paleozoic Era on the Geologic Time Scale. At this time in the history of Earth, life was in its early stages. The first known life forms appeared about 3.6 billion years ago, but by the Ordovician Period, larger aquatic life forms had come into existence.The results show how El Niño responds to natural factors over extended periods, while highlighting the increasing role of human activities in shaping this climatic phenomenon in the modern era.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 ...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 amounts of life forms from the oceans moved onto the land. Plants were the first to make the move, followed by invertebrates. Not long afterward, vertebrates took to the land.The Neoproterozoic is the terminal era of the Proterozoic eon (or informally, the Precambrian) extending from about 1,000 million years ago (mya) at the end of the Mesoproterozoic to 542 mya at the beginning of the Cambrian of the Paleozoic era. It is one of three major divisions (eras) of the Proterozoic in the geologic time scale . The Paleozoic Era, meaning "ancient life" is the first of three eras that form a part of the Phanerozoic Eon, the other two periods being the Mesozoic and the Cenozoic. The Mesozoic is the age of the Dinosaurs and the Cenozoic is the era in which we now live. The Paleozoic Era spanned a longer period of time, from approximately 542 Ma to 251 Ma. The periods that followed the Cambrian during the Paleozoic Era are marked by further animal evolution and the emergence of many new orders, families, and species. As animal phyla continued to diversify, new species adapted to new ecological niches. During the Ordovician period, which followed the Cambrian period, plant life first appeared on land.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.Mesozoic Era. Of, relating to, or being the era of geologic time from about 251 to 66 million years ago. The Mesozoic Era includes the Triassic, Jurassic, and Cretaceous Periods and is characterized by the development of flying reptiles, birds, and flowering plants and by the appearance and extinction of dinosaurs. Cenozoic Era.The geologic era in which humans have evolved and spread over the Earth is the Cenozoic Era. This time period began roughly 65 million years before the start of the 21st century. The Cenozoic Era began at the end of the Mesozoic Era when th...8.6: Paleozoic. Figure 8.6.1 8.6. 1: The trilobites had a hard exoskeleton and were an early arthropod, the same group that includes modern insects, crustaceans, and arachnids. The Phanerozoic eon is the most recent eon and represents time in which fossils are common, 541 million years ago to today.Paleozoic era. Paleozoic era pāˌlēəzōˈĭk [ key], a major division (era) of geologic time (see Geologic Timescale, table geologic timescale, table) occurring between 570 to 240 million years ago. It is subdivided into six periods, the Cambrian, Ordovician, Silurian, Devonian, Carboniferous, and Permian (see each listed individually).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 ....