The Devonian period is a geological interval in the Paleozoic Era that spans between the Silurian and the Carboniferous. It marks the first transition of vascular plants and certain animals from ...Paleozoic Era. 570 to 240 million years ago; Period Millions of Years Ago Description of Events; Permian: 299: Deposition continues in the Oquirrh and Paradox basins. Red rocks form in the Paradox basin of sediments shed from the Uncompahgre highland. Pennsylvanian: 323: Seas containing fusulinids, brachiopods, and conodonts cover most of Utah.The Paleozoic era came to a sudden end around 252 mya with the single largest extinction event in Earth’s history. The Permian-Triassic extinction event —also known as “the great dying”—saw the sudden disappearance of 80 to 96 percent of all marine species and almost 70 percent of all land vertebrate species around 252 mya.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 Morocco, throughout western Africa, and ...The Jurassic period, which occurred 208 to 146 million years ago, marks the middle of the Mesozoic era, known as the age of dinosaurs. Pangaea, the giant land mass, began to break up and sea levels rose. Evidence indicates that temperatures on Earth were more equable in the Jurassic period than they are today. Temperate zones likely …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 ( IPA: /ˌpæli.əˈzoʊ.ɪk,-i.oʊ-, ˌpeɪ-/ PAL-ee-ə-ZOH-ik, -ee-oh-, PAY-; [1] 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]The Paleozoic Era started 542 million years ago with the emergence of complex life forms and ended 251 million years ago with the largest mass extinction the world has ever experienced. It is the ... Jul 1, 2005 · Pangaea was assembled only at the end of the Paleozoic era, approximately 250 million years ago. It started to fragment during the Jurassic period of the Mesozoic era, about 170 million years ago ... Evolution of fish. The Devonian period 419–359 Ma (Age of Fishes) saw the development of early sharks, armoured placoderms and various lobe-finned fishes including the tetrapod transitional species. The evolution of fish began about 530 million years ago during the Cambrian explosion.Sep 21, 2023 · Devonian Period, in geologic time, an interval of the Paleozoic Era that follows the Silurian Period and precedes the Carboniferous Period, spanning between about 419.2 million and 358.9 million years ago. It is sometimes called the ‘Age of Fishes’ because of the diverse and abundant fishes found in Devonian seas. ... paleozoic-timeline Paleozoic Timeline. photo. Paleozoic Timeline. a timeline of the paleozoic era. Smithsonian Institution · Smithsonian Ocean · Follow us on ...Results 1 - 60 of 104 ... Check out our paleozoic era selection for the very best in unique or custom, handmade pieces from our laptop decals shops.Feb 21, 2013 · Mollusks developed hard structures early in the Paleozoic period (550–250 mya).6 Archaeogastropods flourished during the Paleozoic period: Their shells were frequently larger, broader, planispiral, and contained an umbilicus, the gap at the base of the shell where whorls do not fully overlap (Fig. 2a).6–8 During the Mesozoic period (250 ...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.Jun 5, 2019 · One of the horseshoe crab’s great mysteries — the thing that makes it weirder than almost anything else alive — is that it hasn’t changed since the Ordovician period of the Paleozoic. That’s close to an eon of geologic time. The crabs cruising today’s shores are absolutely identical to the crabs that crawled around post-Pangaean waters.Paleozoic Era. 570 to 240 million years ago; Period Millions of Years Ago Description of Events; Permian: 299: Deposition continues in the Oquirrh and Paradox basins. Red rocks form in the Paradox basin of sediments shed from the Uncompahgre highland. Pennsylvanian: 323: Seas containing fusulinids, brachiopods, and conodonts cover most of Utah.538.8 Ma – 251.9 Ma and contains the Cambrian, Ordovician, Silurian, Devonian, Carboniferous and Permian periods. With only a handful of species surviving today, the Nautiloids flourished during the early Paleozoic era, from the Late Cambrian, where they constituted the main predatory animals.Dec 3, 2021 · The Upper Paleozoic period in the Bohai Bay Basin experienced long-term tectonic evolution both in the Mesozoic and Cenozoic periods, with multiple subsidences and uplifts [9,10]. The diagenetic sequences of tight sandstones in the Carton basins, such as the Ordos and Sichuan basins, have been studied extensively [ 11 , 12 ].The Precambrian was the "Age of Early Life." During the Precambrian, continents formed and our modern atmosphere developed, while early life evolved and flourished. Soft-bodied creatures like worms and jellyfish lived in the world's oceans, but the land remained barren. Common Precambrian fossils include stromatolites and similar structures ...The name Paleozoic ( IPA: / ˌpæli.əˈzoʊ.ɪk, - i.oʊ -, ˌpeɪ -/ pal-ee-ə-ZOH-ik, -ee-oh-, pay- ;) was coined by the British geologist Adam Sedgwick in 1838 by combining the Greek words palaiós ( παλαιός, "old") and zōḗ ( ζωή, "life") meaning "ancient life".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 …Prehistoric Amphibian Pictures and Profiles. During the Carboniferous and Permian periods, prehistoric amphibians, and not reptiles, were the apex predators of the earth's continents. On the following slides, you'll find pictures and detailed profiles of over 30 prehistoric amphibians, ranging from Amphibamus to Westlothiana.443 million Years Ago. Graptolites of the Ordovician period. Image credit Aunt Spray via Shutterstock. The Ordovician-Silurian period saw earth's first mass extinction 443 million years ago. Approximately 85% of the earth’s species disappeared. Scientists believe climate change caused mass extinction.Online exhibits: Geologic time scale. The Cenozoic Era. The Cenozoic Era is the most recent of the three major subdivisions of animal history. The other two are the Mesozoic and Paleozoic Eras. The Cenozoic spans only about 65 million years, from the end of the Cretaceous Period and the extinction of non-avian dinosaurs to the present. The …Periods of the Paleozoic Era include: Cambrian; Ordovician; Silurian; Devonian; Carboniferous (sometimes separated into the ...Jul 1, 2005 · Pangaea was assembled only at the end of the Paleozoic era, approximately 250 million years ago. It started to fragment during the Jurassic period of the Mesozoic era, about 170 million years ago ... Sep 21, 2023 · Devonian Period, in geologic time, an interval of the Paleozoic Era that follows the Silurian Period and precedes the Carboniferous Period, spanning between about 419.2 million and 358.9 million years ago. It is sometimes called the ‘Age of Fishes’ because of the diverse and abundant fishes found in Devonian seas. Section 3: The Paleozoic Era. • First four-legged animals developed began. The Paleozoic Era lasted from about 540 million years ago to about 248 million years ago. During this time period of about 292 million years, shallow seas came inland several times. Sharks and other fish, along with many other kinds of animals, lived in the water. Pennsylvanian Time Span. Date range: 323.2 million years ago–298.9 million years ago. Length: 24.3 million years (0.54% of geologic time) Geologic calendar: December 6 (9 PM)–December 8 (7 AM) (1 day, 10 hours) Pennsylvanian age fossil tracks, Grand Canyon National Park, Arizona. NPS image.Feb 13, 2017 · Amniotes appeared around 312 million years ago in the late Carboniferous Period of the Paleozoic Era. The early amniotes were small, lizard-like animals. Freed from the constraints of having to return to the water to breed, they could inhabit a wide range of habitats. The amniotes soon split into two main branches: the synapsids, and the ...Sep 1, 2021 · The basement of the Eastern Alps is a collage of allochthonous terranes and tectonostratigraphic units, which were mobile during the late Precambrian and Paleozoic period (Frisch and Neubauer, 1989).This collage mainly consists of pre-Alpine metamorphic basement nappes, including the Penninic, Austroalpine and Southalpine units (Fig. 1; …Jul 16, 2018 · His main research interests are the Precambrian basements and Paleozoic tectonic evolution of the Central Tianshan Block and the Neoproterozoic NE Jiangxi ophiolitic mélange in the Jiangnan Orogen using geochronology, petrology and geochemistry. ... Yifang Sun, Haonan Li, Orogenic Movements during the Paleozoic …Aug 25, 2023 · 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. 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]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 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 Morocco, throughout western Africa, and ...Early Paleozoic period rocks are seen in the Himalayan Mountain Ranges and they comprise layers originating from the south, worn down from the crystalline craton and put on the Indian territory.The Paleozoic Era spanned that period of geologic time during which the evolution of the first invertebrates, vertebrates, terrestrial (land-based) plants, bony fish, …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. Later Paleozoic periods saw the rise of terrestrial life, notably ferns, the first trees, and tetrapods, widely diverse creatures ranging from lizard-like to snake-like in appearance. Alongside tetrapods, Earth was introduced to its first land-living arthropods, the ancient ancestors of spiders.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 ...Eons are divided into eras, which are further divided into periods, epochs, and ages. Geologic dating is extremely imprecise. For example, although the date listed for the beginning of the Ordovician period is 485 million years ago, it is actually 485.4 with an uncertainty (plus or minus) of 1.9 million years.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 ... Aug 23, 2023 · Precambrian, period of time extending from about 4.6 billion years ago (the point at which Earth began to form) to the beginning of the Cambrian Period, approximately 541 million years ago. The Precambrian represents more than 80 percent of the total geologic record. Remainder of Paleozoic. The Silurian was a period of increasing gastropod diversity in most gastropod clades, as part of the recovery from the end-Ordovician mass extinction. Species with high spires became more common, as did taxa with slits at their apertures (Fryda et al 2008: p. 261). Platyceratids also diversified at this time.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” and the Greek word zoe – which means “life.”. Which is an apt name for this period in Earth history because this is when life really began to take ... Early Paleozoic period rocks are seen in the Himalayan Mountain Ranges and they comprise layers originating from the south, worn down from the crystalline craton and put on the Indian territory.Study the diagram of the geologic time scale. A time scale measured in Millions of years ago or M Y A. Cenozoic Era includes Quaternary Period, 0 to 1.6 M Y A, and Tertiary Period, 1.6 to 66.4 M Y A. Mesozoic Era includes Cretaceous Period, 66.4 to 144 M Y A, Jurassic Period, 144 to 208 M Y A, Triassic Period, 208 to 245 M Y A. Paleozoic Era includes Permian Period, 245 to 286 M Y A ...“It’s a phenomenon in the late Paleozoic period that we had these large arthropods,” says Conrad Labandeira, PhD, a senior research scientist in the department of paleobiology and curator of ...Paleontology in Tennessee refers to paleontological research occurring within or conducted by people from the U.S. state of Tennessee. During the early part of the Paleozoic era, Tennessee was covered by a warm, …Deep Time. Intro | Precambrian Eon | Paleozoic Era | Mesozoic Era | Cenozoic Era. Paleozoic Era: (543-248 mya). Cambrian | Ordovician | Silurian | Devonian ...Jun 5, 2019 · One of the horseshoe crab’s great mysteries — the thing that makes it weirder than almost anything else alive — is that it hasn’t changed since the Ordovician period of the Paleozoic. That’s close to an eon of geologic time. The crabs cruising today’s shores are absolutely identical to the crabs that crawled around post-Pangaean waters.Jul 8, 2023 · Paleozoic Era (541 to 252 million years ago): Fossils from this time period include trilobites, brachiopods, early fish and amphibians, and coral reefs. Mesozoic Era (252 to 66 million years ago): Fossils from this time period include dinosaurs, ammonites, and early birds and mammals. After the Precambrian era ended, various thick geological rock formations such as limestone, sandstone, and shale were deposited during the Paleozoic period (541 to 252 million years ago).PALEOZOIC ERA. KNOWN AS THE AGE OF FISH OR TRILOBITES. Paleozoic Era. Timeframe: 544 million to 248 million years ...From single-celled organisms to wooly mammoths; from bacterial algae to palm fronds, Wyoming hosts a diverse array of terrestrial and marine plant and animal fossils. Browse the geologic eras in the tabs below for more detail on Wyoming's fossil record. Precambrian (4.6 Ga–541 Ma) Paleozoic (541–252 Ma) Mesozoic (252–66 Ma) Cenozoic (66 ... The Paleozoic Era started 542 million years ago with the emergence of complex life forms and ended 251 million years ago with the largest mass extinction the world has ever experienced. It is the ... Apr 28, 2023 · The Precambrian was the "Age of Early Life." During the Precambrian, continents formed and our modern atmosphere developed, while early life evolved and flourished. Soft-bodied creatures like worms and jellyfish lived in the world's oceans, but the land remained barren. Common Precambrian fossils include stromatolites and similar structures ... The 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 : relating to the corresponding ... The Carboniferous Period is famous for its vast swamp forests, such as the one depicted here. Such swamps produced the coal from which the term Carboniferous, or "carbon-bearing," is derived. The Carboniferous Period lasted from about 359.2 to 299 million years ago* during the late Paleozoic Era. The term "Carboniferous" comes from England, in ...Figure 15.6. 1: Trilobites, by Heinrich Harder, 1916. The Paleozoic era was dominated by marine organisms, but by the middle of the era, plants and animals had evolved to live and reproduce on land, including amphibians and reptiles. Fish evolved jaws and fins evolved into limbs. Lungs evolved and life emerged from the sea onto land to become ...根据Takhtajan世界植物区系分区对报春花科22属在世界各地以及在中国各省区的分布作了较详细的统计，在此基础上，将报春花科各属归纳为10个分布型，认为中国西部横断山区和东西马拉雅为报春花科的现代分布中心和多样化中心；高加索—阿尔卑斯山脉为第二 ...Feb 13, 2017 · Amniotes appeared around 312 million years ago in the late Carboniferous Period of the Paleozoic Era. The early amniotes were small, lizard-like animals. Freed from the constraints of having to return to the water to breed, they could inhabit a wide range of habitats. The amniotes soon split into two main branches: the synapsids, and the ...1 Jun 2017 ... This glaciation was followed in the Cambrian Period by a long, warmer interval without recorded ice sheets upon the Gondwana supercontinent.Feb 2, 2023 · 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 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 marked by an unprecedented boom of invertebrates and a subsequent spread of higher plants, fishes, and amphibians. Not only individual ...Mar 18, 2021 · Trilobites are a diverse group of prehistoric marine invertebrate animals that first appeared around 521 mya (million years ago), during the Cambrian Period of the Paleozoic Era. Trilobites are among the most successful early multicellular animals and were present on Earth for over 250 million years (that’s many millions of years longer than ... Oct 3, 2022 · This discovery shows evidence that major vertebrate groups began to diversify tens of millions of years before the beginning of the Devonian period, or the Age of Fishes, about 419.2 million and ...The Paleozoic Era marks life before the time of the dinosaurs. Remarkably diverse species of marine fauna such as trilobites, brachiopods, crinoids, blastoid ...The Jurassic period, which occurred 208 to 146 million years ago, marks the middle of the Mesozoic era, known as the age of dinosaurs. Pangaea, the giant land mass, began to break up and sea levels rose. Evidence indicates that temperatures on Earth were more equable in the Jurassic period than they are today. Temperate zones likely …17 Jun 2023 ... Understanding the Paleozoic: A Geological Time Frame · The Cambrian Period (538.8–485.4 million years ago) · The Ordovician Period (485.4–443.8 ...Paleozoic Era, or Palaeozoic Era , Major interval of geologic time, c. 542–251 million years ago. Aug 23, 2023 · Precambrian, period of time extending from about 4.6 billion years ago (the point at which Earth began to form) to the beginning of the Cambrian Period, approximately 541 million years ago. The Precambrian represents more than 80 percent of the total geologic record. Jan 1, 1994 · It’s known that the gradual scissor-like closure of the Paleo-Asian Ocean occurred from west to east during the Paleozoic period. However, it was not until the Triassic period that the complete ...The geologic time scale is the “calendar” for events in Earth history. It subdivides all time into named units of abstract time called—in descending order of duration— eons, eras, periods, epochs, and ages.The enumeration of those geologic time units is based on stratigraphy, which is the correlation and classification of rock strata. The fossil forms that …A recent study by Edwards et al. 55, has used this equation to estimate atmospheric oxygen concentrations in the early Paleozoic from the δ 13 C record in organic C and carbonates, using values ...538.8 Ma – 251.9 Ma and contains the Cambrian, Ordovician, Silurian, Devonian, Carboniferous and Permian periods. With only a handful of species surviving today, the Nautiloids flourished during the early Paleozoic era, from the Late Cambrian, where they constituted the main predatory animals.Common Paleozoic fossils include trilobites and cephalopods, as well as insects and ferns. The greatest mass extinction in Earth's history ended this era. Paleozoic Resources. The Paleozoic Era is further divided in to seven periods/sub-periods: the Cambrian, the Ordovician, the Silurian, the Devonian, the Mississippian, the Pennsylvanian, the ...In addition to the relative dating of periods in Earth's history for which we have rocks preserved, geologists are now able to assign absolute age dates to critical intervals. In the Geologic Time Scale, time is generally divided on the basis of the earth's biotic composition, with the Phanerozoic Eon (i.e. the Paleozoic, Mesozoic and Cenozoic ...Paleozoic Era. 570 to 240 million years ago; Period Millions of Years Ago Description of Events; Permian: 299: Deposition continues in the Oquirrh and Paradox basins. Red rocks form in the Paradox basin of sediments shed from the Uncompahgre highland. Pennsylvanian: 323: Seas containing fusulinids, brachiopods, and conodonts cover most of Utah. You may be familiar with the chemical periodic table from school, but there’s more than meets the eye with this seemingly simple scientific chart. Learn more about the periodic table, including how it was developed and which elements have s...The Paleozoic Era begins after the Pre-Cambrian about 297 million years ago and ends with the start of the Mesozoic period about 250 million years ago. Each major era on the Geologic Time Scale has been further broken down into periods that are defined by the type of life that evolved during that span of time.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 Paleozoic era spanned roughly (Ma) and is subdivided into six geologic periods; from oldest to youngest, they are the Cambrian, Ordovician, Silurian, Devonian, Carboniferous and Permian. Geologically, the Paleozoic starts shortly after the breakup of a supercontinent called Pannotia and at the end of a global ice age.Tertiary Period, former official interval of geologic time lasting from approximately 66 million to 2.6 million years ago. It is the traditional name for the first of two periods in the Cenozoic Era (66 …The Late Ordovician mass extinction (LOME), sometimes known as the end-Ordovician mass extinction or the Ordovician-Silurian extinction, is the first of the "big five" major mass extinction events in Earth's history, occurring roughly 443 Mya. [1] It is often considered to be the second-largest known extinction event, in terms of the percentage ...Introduction. 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. The Paleozoic was the first of the three major eras of the Phanerozoic Eon; this is reflected in its name: paleozoic is ... During the early part of the Paleozoic Era (approximately 600 million to 350 million years ago), broad, relatively shallow seas repeatedly inundated the Texas Craton and much of North and West Texas. The evidence for these events is found exposed around the Llano Uplift and in far West Texas near Van Horn and El Paso, and also in the subsurface ...19 Des 2019 ... KNOWN AS THE AGE OF FISH OR TRILOBITES. Life starts in the seas and moves onto land. Paleozoic Era. Six periods : Cambrian Ordovician Silurian ...It’s easy to get distracted by the abundance and diversity of life that appears and flourishes during the Paleozoic. But, Aug 10, 2012 · The Ordovician* lasted about 45 million years and saw the transition from very, Cambrian Period, earliest time division of the Paleozo, Paleozoic Era, or Palaeozoic Era , Major interval of geologic, The Permian Period . The Permian period began 299 million years ago at the end, The term ‘Paleozoic’ has been derived from Greek words: palaiosmeaning ‘ancient’ and zoe meaning ‘life’. This era span, The end of the Paleozoic era is marked by the largest mass extinction , Paleozoic Era, major interval of geologic time that began 538.8 , You may be familiar with the chemical periodic table from , The Paleozoic Era started 542 million years ago with the emergenc, Apr 11, 2022 · The Late Paleozoic period o, The Paleozoic period…was a time of huge and abundant p, The Paleozoic Era spanned that period of geologic time durin, Europe - Geology, Tectonics, Plate Boundaries: The ge, MIT geologists have now reconstructed a timeline of the Ear, The Devonian period is a geological interval in the Paleozoic Era, The Paleozoic Era is divided into the Cambrian, Ordo, The Paleozoic Era was a major interval of geologic time..