What are the periods of the paleozoic era

The Paleozoic Era · Global paleogeographic reconstruction of the Earth in the Early Cambrian period 540 million years ago. · Global paleogeographic reconstruction ...

What are the periods of the paleozoic era. 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.

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 Mesozoic Era began 252.2 million years ago, following the conclusion of the Paleozoic Era, and ended 66 million years ago, at the dawn of the Cenozoic Era. (See the geologic time scale.) The major divisions of the Mesozoic Era are, from oldest to youngest, the Triassic Period, the Jurassic Period, and the Cretaceous Period.The Paleozoic Era is divided into the Cambrian, Ordovician, Silurian, Devonian, and Carboniferous periods, each with characteristic groups of fossils.The Cambrian Period is the first geological time period of the Paleozoic Era (the “time of ancient life”). The period gets its name from Cambria, the Roman name for Wales, where Adam Sedgwick, one of the pioneers of geology, studied rock strata. What was the weather like in the Paleozoic era? The Paleozoic Era also saw a variety of …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 …The Paleozoic era is classified into a set of six periods, which are: Cambrian or Cambrian (541 ma ago – 485 ma ago). This period is characterized by the “great explosion” of life, which crowded the seas and gave way, for the first time in the history of the planet, to multicellular living beings, much more complex than protists and bacteria.The Phanerozoic Eon represents geologic time from the end of Precambrian time, approximately 544 to 570 million years ago (mya), until the present day. As such, the Phanerozoic Eon includes the Paleozoic Era , the Mesozoic Era , and the current Cenozoic Era . The Phanerozoic Eon and constituent eras are then further divided into 12 geologic ...

Ordovician Period, in geologic time, the second period of the Paleozoic Era. It began 485.4 million years ago and ended 443.8 million years ago. The interval was a time of intense diversification (an increase in the number of species) of marine animal life in what became known as the Ordovician radiation.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 …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. What is the Carboniferous? and more. 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 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. The water completely covered the area that we now call North Dakota and at times ...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 is divided into five different periods: Cambrian Period: Life at this stage was at sea and did not exist on land. Oceans were shallow and large invertebrates and …

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 ...Devonian Period, Interval of geologic time, 419.2–358.9 million years ago. It was the fourth period of the Paleozoic Era. During the Devonian a giant continent was situated in the Southern Hemisphere (see Gondwana), and other landmasses were located in the equatorial regions. Siberia was separated from Europe by a broad ocean, and North ...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 is divided into six periods: Cambrian, Ordovician, Silurian, Devonian, Carboniferous and Permian. Cambrian Period: é responsible for one of the greatest organic expansions of the Era in three types: Lower Cambrian, Middle Cambrian and Upper Cambrian. Its period started around 542 million years ago and can …Geologic History: Geologists have determined that the Earth has existed for roughly 4.5 billion years from using radioisotope dating on its oldest rocks. This time has been split into different sections that occupy different periods of time, with older periods such as those in the Precambrian occurring for hundreds of millions of years, while ...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 ...

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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 ...Permian Period: The Permian period ended with the largest mass extinction in Earth’s history, where nearly 96% of marine species and 70% of terrestrial life died out. This event marked the end of the Paleozoic Era . Paleozoic Climate and Continental Movement. The Paleozoic Era was a time of dramatic geological and climatic changes.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 ... The Paleozoic Era is divided into six periods: Cambrian, Ordovician, Silurian, Devonian, Carboniferous and Permian. Cambrian Period: é responsible for one of the greatest organic expansions of the Era in three types: Lower Cambrian, Middle Cambrian and Upper Cambrian. Its period started around 542 million years ago and can …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 …

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 paleozoic era is the earliest of three geologic eras of the Phanerozoic eon. 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 Cambrian, Ordovician, Silurian, Devonian, Carboniferous, and Permian.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 ...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 period lasted about 325 million years, from about 570 million years ago to about 245 million years ago. So much happened during the Paleozoic that it is divided into seven geologic time periods, shown on the red steps of the "Staircase of Time". Many different things happened during each period, but we can only give a summary here.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 : …The Paleozoic ("old life") era was the first and longest era of the Phanerozoic eon, lasting from 538.8 to 251.9 Ma. During the Paleozoic, many modern groups of life came into existence. Life colonized the land, first plants, then animals. Two major extinctions occurred.Paleo, Meso, Neo. The Geologic Time Scale is divided into four classes of measured time. List in order from largest to smallest. Eons, Eras, Periods, Epochs. Study with Quizlet and memorize flashcards containing terms like List all Eons in order. (Oldest to Youngest), List all Eras in order (Oldest to Youngest), List all Eras in Archean Eon ...

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 ...

The Silurian (/ s ɪ ˈ lj ʊər iː ən, s aɪ-/ sih-LURE-ee-ən, sy-) is a geologic period and system spanning 24.6 million years from the end of the Ordovician Period, at 443.8 million years ago (), to the beginning of the Devonian Period, 419.2 Mya. The Silurian is the shortest period of the Paleozoic Era.As with other geologic periods, the rock beds that define …Sep 2, 2023 · Kids Encyclopedia Facts. The Paleozoic (or Palaeozoic) Era from the Greek palaios (παλαιός), "old" and zoe (ζωή), "life", meaning "ancient life") is the earliest of three geologic eras of the Phanerozoic Eon. It is the longest of the Phanerozoic eras, lasting from 541 to 251.902 million years ago, and is subdivided into six geologic ... 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 ...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 ...Series: Geologic Time Periods in the Paleozoic Era. During the Paleozoic Era (541 to 252 million years ago), fish diversified and marine organisms were very abundant. In North America, the Paleozoic is characterized by multiple advances and retreats of shallow seas and repeated continental collisions that formed the Appalachian Mountains. 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 Paleozoic Era is divided into six distinct geological time periods, namely: Cambrian, Ordovician, Silurian, Devonian, Carboniferous, and Permian. Cambrian ...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 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.

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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 Paleozoic is divided into six periods: Cambrian, Ordovician, Silurian, Devonian, Carboniferous and Permian. Continental Masses The ancient supercontinent …The Paleozoic is subdivided into six geologic periods (from oldest to youngest): Cambrian Ordovician Silurian Devonian Carboniferous PermianPhanerozoic Eon The Phanerozoic Eon represents geologic time from the end of Precambrian time, approximately 544 to 570 million years ago (mya), until the present day. As such, the Phanerozoic Eon includes the Paleozoic Era , the Mesozoic Era , and the current Cenozoic Era . The Phanerozoic Eon and constituent eras are then further …The Paleozoic Era is a geologic age that spanned 540 to 252 million years ago. In this era, the Earth saw a dramatic change. Not only did it see a drastic increase in new species, but it also saw the rise and fall of many different animals and plants. If you have questions or need any information on the Paleozoic Era, please fill out the ...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 time scale is divided into four large periods of time—the Cenozoic Era, Mesozoic Era, Paleozoic Era, and The Precambrian. Cenozoic Era. The Cenozoic Era (66 million years ago through today) is the "Age of Mammals." Birds and mammals rose in prominence after the extinction of giant reptiles. Common Cenozoic fossils include cat …The Cambrian Explosion (was a good thing!) ... The Paleozoic Era began with the Cambrian Explosion, a rapid period of life flourishing on Earth. Vast amounts of ...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 ...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, 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. ….

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 ... 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: 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 ...Oct 19, 2023 · 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. What major event was taking place in the late Paleozoic? 3. The late Paleozoic was a time when the continents assembled to form the supercontinent of Pangea. What are the periods in the Paleozoic Era in order? Paleozoic Resources The Paleozoic Era is further divided in to seven periods/sub-periods: the Cambrian, the Ordovician, the Sulurian, the …The passive margin that existed around Laurentia continued into the. Early Ordovician Period. The paleogeography of Laurentia, as shown in Figure 23-6A, was ...Series: Geologic Time Periods in the Paleozoic Era. During the Paleozoic Era (541 to 252 million years ago), fish diversified and marine organisms were very abundant. In North America, the Paleozoic is characterized by multiple advances and retreats of shallow seas and repeated continental collisions that formed the Appalachian Mountains.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. What are the periods of the paleozoic era, Paleozoic Era. The Paleozoic era begins with the Cambrian radiation, a time of great growth in the number of different kinds of animals in the oceans. It ends with the greatest extinction in the history of life. Other major extinction events occurred at the end of the Ordovician Period and near the end of the Devonian Period. The Paleozoic Era ..., 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 ..., (i) Paleozoic era is the era of ancient life. (ii) Ordovician period is the age of vertebraes. (iii) Carboniferous period is the age of reptiles (iv) ..., 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 Permian period lasted from 290 to 248 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 ... , 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 …, From middle to late Permian times Pangea underwent a period of northward drift (Fig. 5), accompanied by a minor counter clockwise rotation, so that by the end of the Paleozoic Era the African core was in an equatorial …, 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 passive margin that existed around Laurentia continued into the. Early Ordovician Period. The paleogeography of Laurentia, as shown in Figure 23-6A, was ..., 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., CO 2 concentrations have been high during periods of particularly warm climate (such as during most of the Mesozoic era and the Eocene epoch) and low during times of cold climate, including the major epochs with periodic glaciations (namely, the Permo-carboniferous and late Cenozoic glaciations), as illustrated in Figure 5.11 and Figure 14.1 …, 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 ..., 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 ..., Answers for first geological period of the paleozoic era crossword clue, 8 letters. Search for crossword clues found in the Daily Celebrity, NY Times, Daily Mirror, Telegraph and major publications. Find clues for first geological period of the paleozoic era or most any crossword answer or clues for crossword answers., 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., 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. , 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 ..., The era where complex multi-cellular life appeared and began to thrive on Earth, the Paleozoic Era encompasses a period of time around 542 to 251 million years ago, with separate periods dividing the era further. Answer and Explanation: Become a Study.com member to unlock this answer! Create your account ..., 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 passive margin that existed around Laurentia continued into the. Early Ordovician Period. The paleogeography of Laurentia, as shown in Figure 23-6A, was ..., Paleozoic Era. From an explosion of early life to the greatest extinction in history, the Paleozoic was a time of change. During this earliest era, living things developed vertebral columns and hard body parts like jaws, bones and teeth. ... The 6 periods in this era are described below, as shown in the "Fossils Tell a Scientific Story" exhibit ..., 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., 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., The Paleozoic is a time in Earth's history when active complex life forms evolved, took their first foothold on dry land, and when the forerunners of all multicellular life on Earth began to diversify. There are six periods in the Paleozoic era: Cambrian, Ordovician, Silurian, Devonian, Carboniferous and Permian., Series: Geologic Time Periods in the Paleozoic Era. During the Paleozoic Era (541 to 252 million years ago), fish diversified and marine organisms were very abundant. In North America, the Paleozoic is characterized by multiple advances and retreats of shallow seas and repeated continental collisions that formed the Appalachian Mountains., 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 ... , 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 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., It is the longest of the Phanerozoic eras, lasting from 538.8 to 251.902, and is subdivided into six geologic periods (from oldest to youngest): The Paleozoic comes after the Neoproterozoic Proterozoic Eon and is followed by the Mesozoic. The Paleozoic was a time of dramatic geological, climatic, and evolutionary change., Ogg, (2020, Elsevier). Cenozoic Era · Mesozoic Era, Paleozoic Era, Precambrian · All Periods. Stage, Age (Ma) GTS 2020, GSSP Location, Latitude, Longitude ..., 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., By Youth and Education in Science 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., The Devonian ( / dɪˈvoʊni.ən, dɛ -/ də-VOH-nee-ən, deh-) [9] [10] is a geologic period and system of the Paleozoic era, spanning 60.3 million years from the end of the Silurian, 419.2 million years ago ( Ma ), to the beginning of the Carboniferous, 358.9 Ma. [11] It is named after Devon, England, where rocks from this period were first ...