The paleozoic era

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 …

The paleozoic era. 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 (542–251 mya) The Paleozoic Era is divided into the Cambrian, Ordovician, Silurian, Devonian, and Carboniferous periods, each with characteristic …

The Second era of the World. The time period between the Precambrian and Mesozoic periods that lasted for nearly 340 million years is the Paleozoic era. This era is divided into several periods like the Cambrian, Ordovician, Silurian, Devonian, Carboniferous and Permian. The Cambrian period was the first part of this era which started ...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 …Africa - Paleozoic, Fossils, Geology: The Paleozoic Era consists of the Cambrian, Ordovician, Silurian, Devonian, Carboniferous, and Permian periods and includes two …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.Oct 5, 2023 · 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 major

The Permian was the last period of the Paleozoic Era (542-250 million years ago), preceded by the Cambrian, Ordovician, Silurian, Devonian and Carboniferous periods. Climate and Geography . As during the preceding Carboniferous period, the climate of the Permian period was intimately linked with its geography.Jan 23, 2017 · The period, and the Paleozoic era, came to a calamitous close 251 million years ago, marking a biological dividing line that few animals crossed. The Permian extinction—the worst extinction ... The force of its movement pressed the floor of a Paleozoic sea deep into the earth's mantle, where, in effect, it melted. ... which, in the era of climate change, has been dubbed "white gold ...Hemichordates are another group now inconspicuous but diverse in the Paleozoic. Most of them are called graptolites, colonoids abundant in the Ordovician Period (485 million to 444 million years ago) and Silurian Period (about 444 million to 419 million years ago). Hemichordates are very primitive deuterostomes related to both echinoderms and ...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.It was during this time that the early chordates developed the skull and the …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 ... The Great Dying brought an end to the Paleozoic Era, and in its wake began a new era that allowed for the diversification of many new lifeforms. This new era became known as the Mesozoic Era ...Dec 6, 2018 · What caused Earth's biggest mass extinction? Scientists have debated until now what made Earth's oceans so inhospitable to life that some 96 percent of marine species died off at the end of the Permian period. New research shows the "Great Dying" was caused by global warming that left ocean animals unable to breathe.

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.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 ... The Second era of the World. The time period between the Precambrian and Mesozoic periods that lasted for nearly 340 million years is the Paleozoic era. This era is divided into several periods like the Cambrian, Ordovician, Silurian, Devonian, Carboniferous and Permian. The Cambrian period was the first part of this era which started ...... paleozoic-timeline Paleozoic Timeline. photo. Paleozoic Timeline. a timeline of the paleozoic era. Smithsonian Institution · Smithsonian Ocean · Follow us on ...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.

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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 3, 2020 · The Paleozoic Era (paleo means "early life") lasted from about 540 to 250 million years ago. Much of Colorado was dominated by two very large mountain ranges …Late in the Paleozoic Era, some 300 million years ago, when the Ancestral Rocky Mountains were being worn by weather to low hills, warm inland seas covered parts of Colorado. Life forms very different from those of today swam and flourished in the waters. Fossil records of those life forms are contained in layers of mudstone and limestone.Jul 5, 2023 · 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 ... During the Paleozoic era, they were extremely abundant. They diversified into a number of different morphologies and even participated in the build-up of ancient reefs. At the end of the Paleozoic, some 250 million years …Study with Quizlet and memorize flashcards containing terms like Which method is most likely used to identify what happened before the start of the Paleozoic era?, Which best describes eras and periods?, Which best explains a primary reason for the inability of life to exist in Earth's early atmosphere? and more.

Mar 23, 2020 · 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 ... Carboniferous period (Paleozoic era): Fossil evidence indicates that the Carboniferous Earth was covered in green: the land was dominated by trees and forests including both seedless and seed-bearing plants. Seedless vascular plants formed large swamp forests that covered most of the land, and were composed of tall trees reaching up to 100 ft ...Aug 10, 2012 · The Ordovician* lasted about 45 million years and saw the transition from very primitive to relatively modern life-forms in the seas. The “Ordovician radiation” which followed the late Cambrian extinctions, lead to a tripling of marine diversity, the greatest increase in the history of life, and giving the highest levels of diversity seen during the Paleozoic Era. Mesozoic. Mesozoic (252-66 million years ago) means 'middle life' and this is the time of the dinosaurs. This era includes the Triassic, Jurassic, and Cretaceous Periods, names that may be familiar to you. It ended with a massive meteorite impact that caused a mass extinction, wiping out the dinosaurs and up to 80% of life on Earth.The Precambrian, Paleozoic, Mesozoic, and Cenozoic Eras. The Geologic Time Scale is the history of the Earth broken down into four spans of time marked by various events, such as the emergence of certain species, their evolution, and their extinction, that help distinguish one era from another. Strictly speaking, Precambrian …Twitter appears to have officially killed off its legacy blue check marks, one of the last remaining vestiges of the pre-Elon Musk era. Twitter appears to have officially killed off its legacy blue check marks, one of the last remaining ves...Jun 20, 2013 · The Paleozoic Era, which ran from 541 million to 251.9 million years ago, was a time of great change on Earth. The era began with the breakup of one supercontinent and the formation of another.... 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 …supercontinent, large landmass that accounts for the vast majority of Earth’s land. Some researchers argue that the threshold for a landmass to be considered a supercontinent is approximately 75 …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 Paleozoic era's Silurian period saw animals and plants finally emerge on land. But first there was a period of biological regrouping following the disastrous climax to the Ordovician. The ...

Paleozoic Fossil Record. In the Paleozoic Era, plant and animal life began to develop greater range and complexity. Insects, reptiles, fish, and invertebrates advanced during this time, as well as vascular plant life. Cambrian exposures in Wyoming represent a transgressive depositional sequence (sandstones overlain by shale and limestone ...Subcategories. This category has the following 21 subcategories, out of 21 total. Paleozoic arachnids ‎ (4 C, 13 P) Paleozoic crustaceans ‎ (4 C, 2 P) Paleozoic insects ‎ (6 C, 1 P) Paleozoic myriapods ‎ (3 C) *. Paleozoic arthropods by continent ‎ (5 C)The brachiopods, dominant through most of the Paleozoic era, will be only a minor marine invertebrate group in the Mesozoic and Cenozoic eras. Marine ...The Paleozoic is subdivided into six geologic periods : 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.Meet the Mammal-Like Reptiles of the Paleozoic Era . Lycaenops. Nobu Tamura. Therapsids, also known as mammal-like reptiles, evolved during the middle Permian period and went on to live alongside the earliest dinosaurs. On the following slides, you'll find pictures and detailed profiles of over three dozen therapsid reptiles, ranging …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 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 ...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 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.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.

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The climate of the late Precambrian, Paleozoic, Mesozoic, Cenozoic, Pleistocene, Holecene, and present eras are described. The development of the earth's temperature regime, biosphere, and the ...Study with Quizlet and memorize flashcards containing terms like Which method is most likely used to identify what happened before the start of the Paleozoic era?, Which best describes eras and periods?, Which best explains a primary reason for the inability of life to exist in Earth's early atmosphere? and more. 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 …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 ...Chapter 2: The Paleozoic Era. The Paleozoic Era (paleo means "early life") lasted from about 540 to 250 million years ago. Much of Colorado was dominated by two very large mountain ranges spanning north to south and parallel to each other. The mountain ranges were eroding during this time span, similar to our present Rocky …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 : …Amphibian - Evolution, Classification, Adaptation: Appearing during the Middle Mississippian Epoch, amphibians likely descended from aquatic tetrapods which had lungs and appendages with internal skeletal …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 ...Online exhibits: Geologic time scale: Paleozoic Era. The Cambrian Period. The Cambrian Period marks an important point in the history of life on Earth; it is the time when most of the major groups of animals first …Aug 3, 2020 · The Paleozoic Era (paleo means "early life") lasted from about 540 to 250 million years ago. Much of Colorado was dominated by two very large mountain ranges …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 term 'Paleozoic' has been derived from Greek words: palaiosmeaning 'ancient' and zoe meaning 'life'. This era spans around 200 million years from about 542 to 252 M.A. (million years ago), and is the largest one in terms of time-span. It's the first era of the Phanerozoic Eon, marking the beginning of life on our planet.Here's the strange thing about amphibian evolution: You wouldn't know it from the small and rapidly dwindling population of frogs, toads, and salamanders alive today, but for tens of millions of years spanning the late Carboniferous and early Permian periods, amphibians were the dominant land animals on Earth. Some of these ancient creatures …Aug 24, 2022 · 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 (541 million years ago to 252 million years ago) featured enough atmospheric oxygen to support mega-sized superbugs.; The largest giant dragonfly, for instance, had a wingspan of ...Aug 24, 2022 · 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. Study with Quizlet and memorize flashcards containing terms like Which method is most likely used to identify what happened before the start of the Paleozoic era?, Which best describes eras and periods?, Which best explains a primary reason for the inability of life to exist in Earth's early atmosphere? and more.May 12, 2020 · 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 ... Plant - Evolution, Paleobotany, Photosynthesis: At present, fossil evidence of land plants dates to the Ordovician Period. The abundance and diversity of plant fossils increase into the Silurian Period, and by the middle Devonian Period, the heterosporous life cycle, which allows for more rapid evolution, had occurred independently in several groups, including lycophytes and the ancestors of ...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 paleozoic era, The Paleozoic Era (542–251 mya) The Paleozoic Era is divided into the Cambrian, Ordovician, Silurian, Devonian, and Carboniferous periods, each with characteristic groups of fossils., 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 second stage coincides with the Paleozoic Era (about 541 to 252 million years ago), during which time the cratons and material accreted to them contributed to the formation first of the supercontinent Gondwana (or Gondwanaland) and …, Table of Contents. South America - Paleozoic, Fossils, Plate Tectonics: The continent’s early Paleozoic rocks depict the breakup of the first supercontinent, an event probably …, Jun 1, 2005 ... (See the geologic timescale!) Geography: Early in the Paleozoic the continents were far apart, but moving tectonic plates caused continents to ..., Rock layers formed during the Paleozoic Era are the most conspicuous in the Grand Canyon’s walls. Coastal environments and several marine incursions from the west between 550 and 250 million years ago deposited sandstone, shale and limestone layers totaling 2,400 to 5,000 feet thick., 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. Life was primitive during the Paleozoic and included many invertebrates (animals without backbones) and the earliest fish and amphibians., 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., Study with Quizlet and memorize flashcards containing terms like In the early stages of the early Paleozoic era the earth was flooded with ______ ____, ..., During the Paleozoic era, they were extremely abundant. They diversified into a number of different morphologies and even participated in the build-up of ancient reefs. At the end of the Paleozoic, some 250 million years …, The Cambrian explosion, Cambrian radiation, [1] Cambrian diversification, or the Biological Big Bang [2] refers to an interval of time approximately 538.8 million years ago in the Cambrian Period of early Paleozoic when there was a sudden radiation of complex life and practically all major animal phyla started appearing in the fossil record., Feb 20, 2014 · The Silurian Period occurred from 443.8 million to 419.2 million years ago. It was the third period in the Paleozoic Era.It followed the Ordovician Period and preceded the Devonian Period.During ... , 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., 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 ..., Noted as a time of dramatic evolutionary, climate and geological change, the Paleozoic Era lasted between 541 to 251.902 million years ago., 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. ..., During the Paleozoic Era (541 to 252 million years ago) Fish diversified and marine organisms were very abundant during the Paleozoic. Common Paleozoic fossils include trilobites and cephalopods such as squid, as well as insects and ferns. The greatest mass extinction in Earth's history ended this era. Learn more and visit parks the preserve ..., Gondwana, also called Gondwanaland, ancient supercontinent that incorporated present-day South America, Africa, Arabia, Madagascar, India, Australia, and Antarctica.It was fully assembled by Late Precambrian time, some 600 million years ago, and the first stage of its breakup began in the Early Jurassic Period, about 180 million years ago. The name …, 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. , Cenozoic Era, third of the major eras of Earth’s history, beginning about 66 million years ago and extending to the present. It was the interval of time during which the continents assumed their modern configuration and geographic positions and during which Earth’s flora and fauna evolved toward those of the present., 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 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 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 ..., Precambrian Time. Learn more about the period that occurred 4.5 billion to 542 million years ago. Precambrian time covers the vast bulk of the Earth's history, starting with the planet's creation ..., The term ‘Paleozoic’ has been derived from Greek words: palaiosmeaning ‘ancient’ and zoe meaning ‘life’. This era spans around 200 million years from about 542 to 252 M.A. (million years ago), and is the largest one in terms of time-span. It’s the first era of the Phanerozoic Eon, marking the beginning of life on our planet., Although Paleozoic means "ancient life" many of the organisms that lived during the later Paleozoic were much closer to those of today than many of the life-forms of the early Paleozoic. Basically, at the risk of generalization, we might say that the earlier Paleozoic was dominated by invertebrates, while the land remained barren., 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 ... , Oct 5, 2023 · 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 major , The second stage coincides with the Paleozoic Era (about 541 to 252 million years ago), during which time the cratons and material accreted to them contributed to the formation first of the supercontinent Gondwana (or Gondwanaland) and …, Paleozoic paleotemperatures based on carbonates and phosphates (Figs. 3, 4) show similar trends such as very high late Cambrian and Early to Middle Ordovician temperatures (> 40 °C), high early ..., The Paleozoic Era, named after the Greek word for "ancient life" (Sedgwick, 1838), is the earliest and longest-lasting era of the Phanerozoic Eon.It began with the Cambrian explosion at ∼538.8 Ma, a major diversification of marine animals, and ended at 251.9 Ma with the end-Permian extinction, the greatest mass extinction in Earth's history (Fig. 1)., May 23, 2019 · 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. , Jan 23, 2017 · The period, and the Paleozoic era, came to a calamitous close 251 million years ago, marking a biological dividing line that few animals crossed. The Permian extinction—the worst extinction ...