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 reference to the rich deposits of coal that occur there. These deposits of coal occur throughout northern Europe, Asia, and midwestern and eastern North America. The term "Carboniferous" is used throughout the world to describe this period, although in the United States it has been separated into the Mississippian (early Carboniferous) and the Pennsylvanian (late Carboniferous) Subsystems. This division was established to distinguish the coal-bearing layers of the Pennsylvanian from the mostly limestone Mississippian, and is a result of differing stratigraphy on the different continents. The Mississippian and Pennsylvanian, in turn, are subdivided into a number of internationally recognized stages based on evolutionary successions of fossil groups . These stages are (from early to late) Tournaisian, Visean, and Serpukhovian for the Mississippian — and Bashkirian, Moscovian, Kasimovian, and Gzhelian for the Pennsylvanian.

In addition to having the ideal conditions for the formation of coal, several major biological, geological, and climatic events occurred during this time. Biologically, we see one of the greatest evolutionary innovations of the Carboniferous: the amniote egg, which allowed for the further exploitation of the land by certain tetrapods. It gave the ancestors of birds, mammals, and reptiles the ability to lay their eggs on land without fear of desiccation. Geologically, the Late Carboniferous collision of Laurasia (present-day Europe, Asia, and North America) into Gondwana (present-day Africa, South America, Antarctica, Australia, and India) produced the Appalachian Mountain belt of eastern North America and the Hercynian Mountains in the United Kingdom. A further collision of Siberia and eastern Europe created the Ural Mountains of Russia. And climatically, there was a trend towards mild temperatures during the Carboniferous, as evidenced by the decrease in lycopods and large insects, and an increase in the number of tree ferns.

The stratigraphy of the Mississippian can be easily distinguished from that of the Pennsylvanian. The Mississippian environment of North America was heavily marine, with seas covering parts of the continent. As a result, most Mississippian rocks are limestone, which are composed of the remains of crinoids, lime-encrusted green algae, or calcium carbonate shaped by waves. The North American Pennsylvanian environment was alternately terrestrial and marine, with the transgression and regression of the seas caused by glaciation. These environmental conditions, with the vast amount of plant material provided by the extensive coal forests, allowed for the formation of coal. Plant material did not decay when the seas covered them, and pressure and heat eventually built up over millions of years to transform the plant material to coal.

Life

The beginning of the Carboniferous generally had a more uniform, tropical, and humid climate than exists today. Seasons if any were indistinct. These observations are based on comparisons between fossil and modern-day plant morphology. The Carboniferous plants resemble those that live in tropical and mildly temperate areas today. Many of them lack growth rings, which suggests a uniform climate. This uniformity in climate may have been the result of the large expanse of ocean that covered the entire surface of the globe, except for a localized section where Pangea, the massive supercontinent that existed during the late Paleozoic and early Triassic, was coming together.

Shallow, warm, marine waters often flooded the continents. Attached filter feeders such as bryozoans, particularly fenestellids, were abundant in this environment, and the sea floor was dominated by brachiopods. Trilobites were increasingly scarce while foraminifers were abundant. The heavily armored fish from the Devonian became extinct, being replaced with more modern-looking fish fauna.

Uplifting near the end of the Mississippian resulted in increased erosion, with an increase in the number of floodplains and deltas. The deltaic environment supported fewer corals, crinoids, blastoids, cryozoans, and bryzoans, which were abundant earlier in the Carboniferous. Freshwater clams made their first appearance, and there was an increase in gastropod, bony fish, and shark diversity. As the continents moved closer to forming Pangea, there was a net decrease in coastline, which in turn affected the diversity of marine life in those shallow continental waters.

Two large ice sheets at the southern pole locked up large amounts of water as ice. With so much water taken out of the water cycle, sea levels dropped, leading to an increase in terrestrial habitat. Increases and decreases in glaciation during the Pennsylvanian resulted in sea level fluctuations that can be seen in the rocks as striped patterns of alternating shale and coal layers.

The uplift of the continents caused a transition to a more terrestrial environment during the Pennsylvanian Subsystem, although swamp forests were widespread. In the swamp forests, seedless plants such as lycopsids flourished and were the primary source of carbon for the coal that is characteristic of the period. The lycopods underwent a major extinction event after a drying trend, most likely caused by increased glaciation, during the Pennsylvanian. Ferns and sphenopsids became more important later during the Carboniferous, and the earliest relatives of the conifers appeared. The first land snails appeared and insects with wings that can't fold back, such as dragonflies and mayflies, flourished and radiated. These insects, as well as millipedes, scorpions, and spiders became important in the ecosystem.

A trend towards aridity and an increase in terrestrial habitat led to the increasing importance of the amniotic egg for reproduction. The earliest amniote fossil was the lizard-like Hylonomus, which was lightly built with deep, strong jaws and slender limbs. The basal tetrapods became more diverse during the Carboniferous. Predators with long snouts, short sprawling limbs and flattened heads such as temnospondyls, like Amphibiamus (above) appeared. Anthracosaurs — basal tetrapods and amniotes with deep skulls and a less sprawling body plan that afforded greater agility — appeared during the Carboniferous and were quickly followed by diapsids which divided into two groups: the marine reptiles, lizards, and snakes, and the archosaurs — crocodiles, dinosaurs, and birds. The synapsids also made their first appearance, and presumably the anapsids did as well, although the oldest fossils for that group are from the Lower Permian

Carboniferous rainforest collapse

The Carboniferous rainforest collapse (CRC) was a minor extinction event that occurred around 305 million years ago in the Carboniferous period. It altered the vast coal forests that covered the equatorial region of Euramerica (Europe and America). This event may have fragmented the forests into isolated refugia or ecological 'islands', which in turn encouraged dwarfism and, shortly after, extinction of many plant and animal species. Following the event, coal-forming tropical forests continued in large areas of the Earth, but their extent and composition were changed.

The Complete History of the Earth: Carboniferous Period Paleo analisis :dancing-roach:

The Age of Giant Insects PBS eons :live-slug-reaction: :bug-facts:

When the Rainforests Collapsed PBS eons :shroomjak:

Walking With Monsters: Life Before Dinosaurs BBC [2] - Reptile's Beginnings :croc-pog:

Walking With Monsters: Life Before Dinosaurs BBC [1] - Water Dwellers :fishe: i forgot to link this one last mega oops

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  • keepcarrot [she/her]
    ·
    2 years ago

    Modern planes have to land. Which is where handheld laser pointers are dangerous.