Paleozoic time period

Online exhibits: Geologic time scale: Paleozoic Era. The Permian Period. The Permian period lasted from 299 to 251 million years ago* and was the last period of the Paleozoic Era. The distinction between the Paleozoic and the Mesozoic is made at the end of the Permian in recognition of the largest mass extinction recorded in the history of life ...

Paleozoic time 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.

This surface also became the floor of the Appalachian geosyncline, the broad trough in which sediments were intermittently deposited from the late Precambrian through Paleozoic time, a period of almost 600 million years. During this time these sediments became the rocks that now form the Appalachian Mountains. LATE PRECAMBRIAN VOLCANISM

The Permian was described from rocks in the region of Perm, a town in the Ural Mountains of Russia. The exception to this naming convention is the Carboniferous; its name means "coal-bearing," and this is a time when extensive coal beds were formed around the world. Life. Two great animal faunas dominated the seas during the Paleozoic. Online exhibits: Geologic time scale: Paleozoic Era. The Permian Period. The Permian period lasted from 299 to 251 million years ago* and was the last period of the Paleozoic Era. The distinction between the Paleozoic and the Mesozoic is made at the end of the Permian in recognition of the largest mass extinction recorded in the history of life ...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 …The Precambrian includes approximately 90% of geologic time. It extends from 4.6 billion years ago to the beginning of the Cambrian Period (about 539 Ma).It includes the first three of the four eons of Earth's prehistory (the Hadean, Archean and Proterozoic) and precedes the Phanerozoic eon.. Major volcanic events altering the Earth's environment and …Like their relatives—starfishes, sea urchins, sea cucumbers, and brittle stars—crinoids are echinoderms, animals with rough, spiny surfaces and a special kind of radial symmetry based on five or multiples of five. Crinoids have lived in the world's oceans since at least the beginning of the Ordovician Period, roughly 485 million years ago.In 1891 Henry Shaler Williams coined the name for the younger strata of the Carboniferous Period that are well exposed in Pennsylvania. ... Part of a series of articles titled Geologic Time Periods in the Paleozoic Era. Previous: Permian Period—298.9 to 251.9 MYA. Next: Mississippian Period—358.9 to 323.2 MYA Tags big south ...The Devonian (/ d ɪ ˈ v oʊ n i. ən, d ɛ-/ də-VOH-nee-ən, deh-) 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 (), to the beginning of the Carboniferous, 358.9 Ma. It is named after Devon, England, where rocks from this period were first studied.. The first significant …Color and learn about ancient life in this Paleozoic Era timescale. Great as a supplemental activity when teaching about the history of life on earth. ...

geologic time scale v. 6.0 cenozoic mesozoic paleozoic precambrian age epoch age picks magnetic period hist. chro n. polarity quater-nary pleistocene* holocene* calabrian gelasian c1 c2 c2a c3 c3a c4 c4a c5 c5a c6 c6a c6b c6c c7 c5b c5c c5d c5e c8 c9 c10 c7a c11 c12 c13 c15 c16 c17 c18 c19 c20 c21 c22 c23 c24 c25 c26 c27 c28 c29 c30 0.012 1.8 3 ... 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, 541 million years ago. The Precambrian encompasses the Archean and Proterozoic eons, which are formal geologic intervals that lasted from 4 billion to about 541 million years ago, and the ...By the time of the Jurassic, the seafloor was again thriving, but the reef's composition was different than the reefs we think of today. Presently, corals are the famous creatures known for their reef-building. They were also fairly abundant at various times through the Paleozoic Era and formed extensive reefs by the Devonian Period.Ordovician Period, in geologic time, the second period of the Paleozoic Era. It began 485.4 million years ago, following the Cambrian Period, and ended 443.8 million years ago, when the Silurian Period...

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 Paleozoic Era is bracketed by the times of global super-continents. The era opened with the breakup of the world-continent Pannotia and closed with the formation of Pangea, as the Earth's continents came together once again. ... The exception to this naming convention is the Carboniferous; its name means "coal-bearing," and this is a time ...Cretaceous Period. Mesosaurus tenuidens is the only species that has been found within the Genus Mesosaurus. It is a genus of reptiles that inhabited our planet millions of years ago, even before the dinosaurs. The time scale in which it lived is known as the Paleozoic Era, prior to the Mesozoic Era which is the “Age of Dinosaurs”, and ...Carboniferous Period - Fossils, Plants, Animals: The Carboniferous was a time of diverse marine invertebrates. The Late Devonian Period experienced major extinctions within some marine invertebrate groups, …

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Jun 11, 2018 · In geologic time , the Paleozoic Era, the first era in the Phanerozoic Eon , covers the time between roughly 544 million years ago (mya) and until 245 mya. The Paleozoic Era spans six geologic time periods including the Cambrian Period (544 to 500 mya); Ordovician Period (500 mya to 440 mya); Silurian (440 mya to 410 mya); Devonian (410 mya to ... Learn about the time period that took place 416 to 359 million years ago. Learn about Earth's Devonian Period and prehistoric life. ... The Devonian, part of the Paleozoic era, ...Geologic Time Scale. Humans subdivide time into useable units such as our calendar year, months, weeks, and days; geologists also subdivide time. They have created a tool for measuring geologic time, breaking it into useable, understandable segments. For the purposes of geology, the “calendar” is the geologic time scale.We don’t know as much about the first 3 billion years of Utah’s geologic history as we know about the 540 million years of the Phanerozoic Eon that followed, but 2.5-billion- to 540-million-year-old rocks are exposed in the Raft River Range, Uinta Mountains, and parts of the Wasatch Range, as well as several other smaller areas of the state.

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.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 is bracketed by the times of global super-continents. The era opened with the breakup of the world-continent Pannotia and closed with the formation of Pangea, as the Earth's continents came together once again. ... The exception to this naming convention is the Carboniferous; its name means "coal-bearing," and this is a time ...All members of these clades were squid-like, but had straight external shells called orthocones. They flourished in Paleozoic oceans between the Ordovician (488 mya) and Triassic periods (200 mya) with shells that, in some species, reached nearly 10 meters in length. More familiar to us in the fossil record are the nautiloids, ammonoids, and ...There is no evidence for life at that time. The Phanerozoic Eon encompasses the period of abundant, complex life on Earth. It began with the start of the Cambrian period, 544 …Regional-scale folding during Early Paleozoic time was in many places accompanied by intensive thrusting and ductile shearing, ... 2010] followed by a northwestward closure of the marine basins through the Late Ordovician-Silurian period [Rong et al., 2003, 2010, 2012].Alfred Wegener, starting in 1912, was the first scientist to discuss supercontinents seriously, as part of his theory of continental motion.He combined a body of new and old evidence to show that the Earth's continents had once been united in a single body, back in late Paleozoic time.Geologic Time Scale. Humans subdivide time into useable units such as our calendar year, months, weeks, and days; geologists also subdivide time. They have created a tool for measuring geologic time, breaking it into useable, understandable segments. For the purposes of geology, the “calendar” is the geologic time scale.

১২ অক্টো, ২০১৪ ... Trilobites are one of the few major groups of organisms that span the majority of the Paleozoic Era. The greatest numbers of trilobite species ...

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 ...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.Each time the shoreface passed across southeastern Minnesota, it left behind sandy deposits. The Mt. Simon Sandstone, the oldest Paleozoic Era formation, was deposited during the initial Cambrian Period flooding of Minnesota, during which the shoreface migrated northward when southeastern Minnesota was covered with water.The Precambrian is the name given to the span of time prior to the Cambrian. The Precambrian period accounts for 88 per cent of geological time. There are very varied deposits from the Neoproterozoic, including volcanic sequences, sedimentary rocks formed in environments from deep water to terrestrial, plutonic igneous rocks and metamorphic …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 ...Chapter 12: Middle Paleozoic Life. 1. Silurian survivors of the Late Ordovician mass extinction were mostly cold-adapted animals from high latitudes or deep waters. 2. Figure 12.3: The following invertebrates continued into the middle Paleozoic, but mostly as new families and orders: (a) crinoids. (b) brachiopods. (c) bryozoans.1996 [3] The Pennsylvanian ( / ˌpɛnsəlˈveɪni.ən / pen-səl-VAYN-i-ən, [4] also known as Upper Carboniferous or Late Carboniferous) is, in the ICS geologic timescale, the younger of two subperiods (or upper of two subsystems) of the Carboniferous Period. It lasted from roughly 323.2 million years ago to 298.9 million years ago.

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Aug 11, 2020 · Geological time has been divided into four eons: Hadean (4570 to 4850 Ma), Archean (3850 to 2500 Ma), Proterozoic (2500 to 540 Ma), and Phanerozoic (540 Ma to present). As shown in Figure 8.1.2 8.1. 2, the first three of these represent almost 90% of Earth’s history. The last one, the Phanerozoic (meaning “visible life”), is the time that ... 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 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 ...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.Each time the shoreface passed across southeastern Minnesota, it left behind sandy deposits. The Mt. Simon Sandstone, the oldest Paleozoic Era formation, was deposited during the initial Cambrian Period flooding of Minnesota, during which the shoreface migrated northward when southeastern Minnesota was covered with water.The Paleozoic Era, meaning 'Ancient Life' in Greek, stretched from 542- 251 Ma, and can be characterized as a time when the Earth was teeming with aquatic life.Formation of this era in India is called Dravidian formation and developed during the time period of 570 to 245 ... industry related spatially and/or genetically with the Upper Paleozoic, ...Sep 24, 2012 · The following review, by time period, of Maine's geologic history draws heavily on the microplate refinement of plate tectonic theory. In addition to the reports cited above, others providing overviews of various aspects of Maine's bedrock geology include Hussey (1988), Guidotti (1989), Ludman (1986), and Osberg and others (1989). The Precambrian Time Span is the earliest time period on the Geologic Time Scale. It stretches from the formation of the earth 4.6 billion years ago to around 600 million years ago and encompasses many Eons and Eras leading up to the Cambrian Period in the current Eon.The Precambrian covers almost 90% of the entire history of the Earth. It has been divided into three eras: the Hadean, the Archean and the Proterozoic. Source: Unknown. The Precambrian Era comprises all of geologic time prior to 600 million years ago. The Precambrian was originally defined as the era that predated the emergence of life in the ...Oct 6, 2023 · Cambrian Period, earliest time division of the Paleozoic Era and Phanerozoic Eon, lasting from 538.8 million to 485.4 million years ago. The Cambrian System, named by English geologist Adam Sedgwick for slaty rocks in southern Wales and southwestern England, contains the earliest record of abundant and varied life-forms. The Cambrian Explosion was the period of time directly following the Precambrian (~540-530 Ma) in which life diversified, or “exploded”. While Precambrian life forms had only soft parts and no true way to move around, animals that evolved in the Cambrian Explosion began to develop teeth, armor, and eyes. ….

Cambrian Case Index Geologic Time Scale. The Cambrian* Period begins the Phanerozoic Eon, the last 542 million years during which fossils with hard parts have existed. It is the first division of the …১০ অক্টো, ২০২৩ ... The Paleozoic era is subdivided into six geologic periods: the Cambrian, Ordovician, Silurian, Devonian, Carboniferous, and Permian. The ...Paleozoic Era, or Palaeozoic Era, Major interval of geologic time, c. 542-251 million years ago. From the Greek for "ancient life," it is the first era of the Phanerozoic Eon and is followed by the Mesozoic Era.It is divided into six periods: (from oldest to youngest) the Cambrian, Ordovician, Silurian, Devonian, Carboniferous, and Permian. ...This was a time of global cooling and warming with ice ages and interglacial periods occurring about every 100,000 years. We are in the beginning of an interglacial period right now (as of 2020). During the glacial periods, the northern quarter of …The highest concentrations of CO2 during all of the Paleozoic Era occurred during the Cambrian Period, nearly 7000 ppm — about 18 times higher than today.Paleozoic Era. The Paleozoic Era lasted from 544 to 245 million years ago. It is divided into six periods. Cambrian Period. The Precambrian mass extinction opened up many niches for new organisms to fill. As a result, the Cambrian Period began with an explosion of new kinds of living things. For example, many types of simple animals called ...This surface also became the floor of the Appalachian geosyncline, the broad trough in which sediments were intermittently deposited from the late Precambrian through Paleozoic time, a period of almost 600 million years. During this time these sediments became the rocks that now form the Appalachian Mountains. LATE PRECAMBRIAN VOLCANISM১০ অক্টো, ২০২৩ ... The Paleozoic era is subdivided into six geologic periods: the Cambrian, Ordovician, Silurian, Devonian, Carboniferous, and Permian. The ... Paleozoic time period, These Paleozoic continents experienced tremendous mountain building along their margins, and numerous incursions and retreats of shallow seas across their interiors. The Paleozoic is divided into seven (or six if you are European) periods based on the dominant forms of life. The earliest period is the Cambrian Period lasting from 540 to 500 mya., SELECT TWO. -It was a series of impacts that occurred well after the planets formed. -It may have bought a significant amount of water to Earth's surface. (NOT: -It helped form the first ocean basins and continents. -It remelted planet Earth into magma again. -It was the highest period of impacts in Earth's history., Compared with Meishan's 30 centimeters of sediments, Penglaitan's sedimentary layers make up a much more expanded 27 meters that were deposited over the same period of time, just before the main ..., geologic time scale v. 6.0 cenozoic mesozoic paleozoic precambrian age epoch age picks magnetic period hist. chro n. polarity quater-nary pleistocene* holocene* calabrian gelasian c1 c2 c2a c3 c3a c4 c4a c5 c5a c6 c6a c6b c6c c7 c5b c5c c5d c5e c8 c9 c10 c7a c11 c12 c13 c15 c16 c17 c18 c19 c20 c21 c22 c23 c24 c25 c26 c27 c28 c29 c30 0.012 1.8 3 ..., 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., After the Baikalian collisions, rifting outboard of the accreted fragments opened a new oceanic area, the floor of which had begun subducting under the enlarged continental nucleus in early Paleozoic time—perhaps during the Ordovician Period (about 485 to 444 million years ago)., There is no evidence for life at that time. The Phanerozoic Eon encompasses the period of abundant, complex life on Earth. It began with the start of the Cambrian period, 544 …, Like their relatives—starfishes, sea urchins, sea cucumbers, and brittle stars—crinoids are echinoderms, animals with rough, spiny surfaces and a special kind of radial symmetry based on five or multiples of five. Crinoids have lived in the world's oceans since at least the beginning of the Ordovician Period, roughly 485 million years ago., 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., During this time, sea level began a cyclic retreat from the continental interiors that would end in a worldwide lowstand at the Mississippian–Pennsylvanian boundary. The Mississippian Subperiod is also recognized as the interval in which armoured fishes, plentiful during the Devonian Period (419.2 to 358.9 million years ago), went largely ..., 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 …, 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., Phanerozoic Eon, the span of geologic time extending about 541 million years from the end of the Proterozoic Eon (which began about 2.5 billion years ago) to the present. The Phanerozoic, the eon of visible life, is divided into three major spans of time largely on the basis of characteristic assemblages of life-forms: the Paleozoic (541 …, Feb 22, 2014 · 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 ... , 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. , 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., 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. Cambrian Period, Ordovician Period, in geologic time, the second period of the Paleozoic Era. It began 485.4 million years ago, following the Cambrian Period, and ended 443.8 million years ago, when the Silurian Period..., As demonstrated by the genus-level plot of their diversity through time (Figure 7.12), tabulate corals suffered badly during the Late Devonian extinction event and never again reclaimed their former levels of diversity. The group went extinct at the end of the Permian period. Figure 7.12 – Diversity of tabulate corals., 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 cambrian and ordovician periods differed fromone another in many ways. Using visual overview, compare two periods with respect to sea level, distribution of landamasses on Earth, and ocean life. Study Chapter 13 flashcards. Create flashcards for FREE and quiz yourself with an interactive flipper., stratigraphic (position) and geochronologic (time) units; that is, eonothem/eon to series/epoch divisions. Workers should refer to the ICS time scale (Ogg, 2004) for stage/age terms. Most systems of the Paleozoic and Mesozoic are subdivided into series utiliz-ing the terms “Lower,” “Middle,” and “Upper.” The geochrono-, Sep 27, 2023 · Updated on September 27, 2023. “The Paleozoic Era (540 to 252 million years ago) was a revolutionary time for new life on Earth. But it had its ups and downs.”. Some of the key highlights from the Paleozoic Era include: CAMBRIAN EXPLOSION: Bony fish diversified during the Cambrian explosion. Just to end in the largest extinction in Earth ... , geologic time scale v. 6.0 cenozoic mesozoic paleozoic precambrian age epoch age picks magnetic period hist. chro n. polarity quater-nary pleistocene* holocene* calabrian gelasian c1 c2 c2a c3 c3a c4 c4a c5 c5a c6 c6a c6b c6c c7 c5b c5c c5d c5e c8 c9 c10 c7a c11 c12 c13 c15 c16 c17 c18 c19 c20 c21 c22 c23 c24 c25 c26 c27 c28 c29 c30 0.012 1.8 3 ... , Cretaceous Period. Mesosaurus tenuidens is the only species that has been found within the Genus Mesosaurus. It is a genus of reptiles that inhabited our planet millions of years ago, even before the dinosaurs. The time scale in which it lived is known as the Paleozoic Era, prior to the Mesozoic Era which is the “Age of Dinosaurs”, and ..., 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 ... , 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 ..., Jun 28, 2017 · Paleozoic Era. The Paleozoic Era lasted from 544 to 245 million years ago. It is divided into six periods. Cambrian Period. The Precambrian mass extinction opened up many niches for new organisms to fill. As a result, the Cambrian Period began with an explosion of new kinds of living things. For example, many types of simple animals called ... , 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., In the late Devonian period, about 370 million years ago, that ecological niche was filled by the 20-foot-long prehistoric fish Titanichthys, which was one of the largest vertebrates of its time (outclassed only by the truly gigantic Dunkleosteus) yet seems to have subsisted on the tiniest fish and single-celled organisms., In the evolutionary history of animal life this radiation was second only to the “Cambrian explosion” in importance. The new Paleozoic fauna created by the “Ordovician radiation” dominated the seas for the next 230 million years. Pandemic species of planktonic graptolites and conodontes appear in the fossil record during this Period., Pangea formed during the two final periods of the late Paleozoic era, the Carboniferous period and the permian period. Life created the amniotic egg during the Carboniferous. Amniotic is just a fancy way to say an egg with a hard shell. Until this time, eggs needed outside moisture to keep them from drying out (think fish eggs)., The Triassic Period (252 to 201 million years ago) kicked off the age of dinosaurs. “Back then, it was extremely hot because concentrations of atmospheric carbon dioxide were five times higher than today’s levels,” explained Olsen. “And yet, marine and terrestrial life was thriving.”. At the beginning of the Triassic Period, the ...