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91-530: Luzula is a genus of flowering plants in the rush family Juncaceae . The genus has a cosmopolitan distribution , with species occurring throughout the world, especially in temperate regions, the Arctic , and higher elevation areas in the tropics . Plants of the genus are known commonly as wood-rush , wood rush , or woodrush . Possible origins of the genus name include the Italian lucciola ("to shine, sparkle") or

182-1868: A molecular phylogeny of plants placed the flowering plants in their evolutionary context: Bryophytes [REDACTED] Lycophytes [REDACTED] Ferns [REDACTED] [REDACTED] [REDACTED] The main groups of living angiosperms are: Amborellales [REDACTED] 1 sp. New Caledonia shrub Nymphaeales [REDACTED] c. 80 spp. water lilies & allies Austrobaileyales [REDACTED] c. 100 spp. woody plants Magnoliids [REDACTED] c. 10,000 spp. 3-part flowers, 1-pore pollen, usu. branch-veined leaves Chloranthales [REDACTED] 77 spp. Woody, apetalous Monocots [REDACTED] c. 70,000 spp. 3-part flowers, 1 cotyledon , 1-pore pollen, usu. parallel-veined leaves   Ceratophyllales [REDACTED] c. 6 spp. aquatic plants Eudicots [REDACTED] c. 175,000 spp. 4- or 5-part flowers, 3-pore pollen, usu. branch-veined leaves Amborellales Melikyan, Bobrov & Zaytzeva 1999 Nymphaeales Salisbury ex von Berchtold & Presl 1820 Austrobaileyales Takhtajan ex Reveal 1992 Chloranthales Mart. 1835 Canellales Cronquist 1957 Piperales von Berchtold & Presl 1820 Magnoliales de Jussieu ex von Berchtold & Presl 1820 Laurales de Jussieu ex von Berchtold & Presl 1820 Acorales Link 1835 Alismatales Brown ex von Berchtold & Presl 1820 Petrosaviales Takhtajan 1997 Dioscoreales Brown 1835 Pandanales Brown ex von Berchtold & Presl 1820 Liliales Perleb 1826 Asparagales Link 1829 Arecales Bromhead 1840 Poales Small 1903 Zingiberales Grisebach 1854 Commelinales de Mirbel ex von Berchtold & Presl 1820 Carboniferous The name Carboniferous means " coal -bearing", from

273-442: A woody stem ), grasses and grass-like plants, a vast majority of broad-leaved trees , shrubs and vines , and most aquatic plants . Angiosperms are distinguished from the other major seed plant clade, the gymnosperms , by having flowers , xylem consisting of vessel elements instead of tracheids , endosperm within their seeds, and fruits that completely envelop the seeds. The ancestors of flowering plants diverged from

364-431: A 100 kyr Milankovitch cycle , and so each cyclothem represents a cycle of sea level fall and rise over a 100 kyr period. Coal forms when organic matter builds up in waterlogged, anoxic swamps, known as peat mires, and is then buried, compressing the peat into coal. The majority of Earth's coal deposits were formed during the late Carboniferous and early Permian. The plants from which they formed contributed to changes in

455-481: A defined GSSP. The fusulinid Aljutovella aljutovica can be used to define the base of the Moscovian across the northern and eastern margins of Pangea, however, it is restricted in geographic area, which means it cannot be used for global correlations. The first appearance of the conodonts Declinognathodus donetzianus or Idiognathoides postsulcatus have been proposed as a boundary marking species and potential sites in

546-431: A shallow, tropical seaway which stretched from Southern California to Alaska. The boundary is within a cyclothem sequence of transgressive limestones and fine sandstones , and regressive mudstones and brecciated limestones. The Moscovian Stage is named after shallow marine limestones and colourful clays found around Moscow, Russia. It was first introduced by Sergei Nikitin in 1890. The Moscovian currently lacks

637-451: A single sedimentary cycle, with an erosional surface at its base. Whilst individual cyclothems are often only metres to a few tens of metres thick, cyclothem sequences can be many hundreds to thousands of metres thick and contain tens to hundreds of individual cyclothems. Cyclothems were deposited along continental shelves where the very gentle gradient of the shelves meant even small changes in sea level led to large advances or retreats of

728-610: A total of 64 angiosperm orders and 416 families. The diversity of flowering plants is not evenly distributed. Nearly all species belong to the eudicot (75%), monocot (23%), and magnoliid (2%) clades. The remaining five clades contain a little over 250 species in total; i.e. less than 0.1% of flowering plant diversity, divided among nine families. The 25 most species-rich of 443 families, containing over 166,000 species between them in their APG circumscriptions, are: The botanical term "angiosperm", from Greek words angeíon ( ἀγγεῖον 'bottle, vessel') and spérma ( σπέρμα 'seed'),

819-624: A tropical wetland environment. Extensive coal deposits developed within the cyclothem sequences that dominated the Pennsylvanian sedimentary basins associated with the growing orogenic belt. Subduction of the Panthalassic oceanic plate along its western margin resulted in the Antler orogeny in the Late Devonian to Early Mississippian. Further north along the margin, slab roll-back , beginning in

910-423: A variety of methods for reconstructing past atmospheric oxygen levels, including the charcoal record, halite gas inclusions, burial rates of organic carbon and pyrite , carbon isotopes of organic material, isotope mass balance and forward modelling. Depending on the preservation of source material, some techniques represent moments in time (e.g. halite gas inclusions), whilst others have a wider time range (e.g.

1001-725: A warmer climate. This rapid rise in CO 2 may have been due to a peak in pyroclastic volcanism and/or a reduction in burial of terrestrial organic matter. The LPIA peaked across the Carboniferous-Permian boundary. Widespread glacial deposits are found across South America, western and central Africa, Antarctica, Australia, Tasmania, the Arabian Peninsula, India, and the Cimmerian blocks, indicating trans-continental ice sheets across southern Gondwana that reached to sea-level. In response to

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1092-858: Is starting to impact plants and is likely to cause many species to become extinct by 2100. Angiosperms are terrestrial vascular plants; like the gymnosperms, they have roots , stems , leaves , and seeds . They differ from other seed plants in several ways. The largest angiosperms are Eucalyptus gum trees of Australia, and Shorea faguetiana , dipterocarp rainforest trees of Southeast Asia, both of which can reach almost 100 metres (330 ft) in height. The smallest are Wolffia duckweeds which float on freshwater, each plant less than 2 millimetres (0.08 in) across. Considering their method of obtaining energy, some 99% of flowering plants are photosynthetic autotrophs , deriving their energy from sunlight and using it to create molecules such as sugars . The remainder are parasitic , whether on fungi like

1183-478: Is derived from the Greek words ἀγγεῖον / angeion ('container, vessel') and σπέρμα / sperma ('seed'), meaning that the seeds are enclosed within a fruit. The group was formerly called Magnoliophyta . Angiosperms are by far the most diverse group of land plants with 64 orders , 416 families , approximately 13,000 known genera and 300,000 known species . They include all forbs (flowering plants without

1274-479: Is limited to Luzula pilosa , and C. sylvaticella feeds only on L. sylvatica . Some species, notably Luzula sylvatica and its cultivars, are used as ornamental garden plants. There are around 140 species in the genus: Flowering plant Basal angiosperms Core angiosperms Flowering plants are plants that bear flowers and fruits , and form the clade Angiospermae ( / ˌ æ n dʒ i ə ˈ s p ər m iː / ). The term 'angiosperm'

1365-508: Is located in Bed 83 of the sequence of dark grey limestones and shales at the Pengchong section, Guangxi , southern China. It is defined by the first appearance of the fusulinid Eoparastaffella simplex in the evolutionary lineage Eoparastaffella ovalis – Eoparastaffella simplex and was ratified in 2009. The Serpukhovian Stage was proposed in 1890 by Russian stratigrapher Sergei Nikitin . It

1456-517: Is named after the Russian village of Gzhel , near Ramenskoye , not far from Moscow. The name and type locality were defined by Sergei Nikitin in 1890. The Gzhelian currently lacks a defined GSSP. The first appearance of the fusulinid Rauserites rossicus and Rauserites stuckenbergi can be used in the Boreal Sea and Paleo-Tethyan regions but not eastern Pangea or Panthalassa margins. Potential sites in

1547-438: Is named after the city of Serpukhov , near Moscow. currently lacks a defined GSSP. The Visean-Serpukhovian boundary coincides with a major period of glaciation. The resulting sea level fall and climatic changes led to the loss of connections between marine basins and endemism of marine fauna across the Russian margin. This means changes in biota are environmental rather than evolutionary making wider correlation difficult. Work

1638-468: Is often a dense cluster of flowers with two leaf-like bracts at the base, or sometimes a solitary flower or a few flowers borne together. They have six brownish tepals . Luzula species are used as food plants by the larvae of some Lepidoptera species, including the smoky wainscot . Several moths of the genus Coleophora have been observed on the plants. Coleophora biforis and C. otidipennella feed exclusively on Luzula . C. antennariella

1729-626: Is that a delay between the development of trees with the wood fibre lignin and the subsequent evolution of lignin-degrading fungi gave a period of time where vast amounts of lignin-based organic material could accumulate. Genetic analysis of basidiomycete fungi, which have enzymes capable of breaking down lignin, supports this theory by suggesting this fungi evolved in the Permian. However, significant Mesozoic and Cenozoic coal deposits formed after lignin-digesting fungi had become well established, and fungal degradation of lignin may have already evolved by

1820-643: Is underway in the Urals and Nashui, Guizhou Province, southwestern China for a suitable site for the GSSP with the proposed definition for the base of the Serpukhovian as the first appearance of conodont Lochriea ziegleri . The Pennsylvanian was proposed by J.J.Stevenson in 1888, named after the widespread coal-rich strata found across the state of Pennsylvania. The closure of the Rheic Ocean and formation of Pangea during

1911-485: The Alismatales grow in marine environments, spreading with rhizomes that grow through the mud in sheltered coastal waters. Some specialised angiosperms are able to flourish in extremely acid or alkaline habitats. The sundews , many of which live in nutrient-poor acid bogs , are carnivorous plants , able to derive nutrients such as nitrate from the bodies of trapped insects. Other flowers such as Gentiana verna ,

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2002-688: The Gulf of Mexico in the west to Turkey in the east. The orogeny was caused by a series of continental collisions between Laurussia, Gondwana and the Armorican Terrane Assemblage (much of modern-day Central and Western Europe including Iberia ) as the Rheic Ocean closed and Pangea formed. This mountain building process began in the Middle Devonian and continued into the early Permian. The Armorican terranes rifted away from Gondwana during

2093-721: The International Commission on Stratigraphy (ICS) stage, but the Viséan is longer, extending into the lower Serpukhovian . North American geologists recognised a similar stratigraphy but divided it into two systems rather than one. These are the lower carbonate-rich sequence of the Mississippian System and the upper siliciclastic and coal-rich sequence of the Pennsylvanian . The United States Geological Survey officially recognised these two systems in 1953. In Russia, in

2184-661: The Kuznetsk Basin . The northwest to eastern margins of Siberia were passive margins along the Mongol-Okhotsk Ocean on the far side of which lay Amuria. From the mid Carboniferous, subduction zones with associated magmatic arcs developed along both margins of the ocean. The southwestern margin of Siberia was the site of a long lasting and complex accretionary orogen. The Devonian to early Carboniferous Siberian and South Chinese Altai accretionary complexes developed above an east-dipping subduction zone, whilst further south,

2275-668: The Latin carbō (" coal ") and ferō ("bear, carry"), and refers to the many coal beds formed globally during that time. The first of the modern "system" names, it was coined by geologists William Conybeare and William Phillips in 1822, based on a study of the British rock succession. Carboniferous is the period during which both terrestrial animal and land plant life was well established. Stegocephalia (four-limbed vertebrates including true tetrapods ), whose forerunners ( tetrapodomorphs ) had evolved from lobe-finned fish during

2366-591: The Latin luzulae or luxulae , from lux ("light"), inspired by the way the plants sparkle when wet with dew . Another etymology sometimes given is that it does derive from lucciola but that this meant a mid-summer field, or from the Latin luculus , meaning a small place; the same source also states that this name was applied by Luigi Anguillara (an Italian botanist ) in 1561. These rushes are usually perennial plants with rhizomes and sometimes stolons . They generally form clumps of cylindrical stems and narrow leaves with hair-lined edges. The inflorescence

2457-566: The Magnitogorsk island arc , which lay between Kazakhstania and Laurussia in the Ural Ocean , collided with the passive margin of northeastern Laurussia ( Baltica craton ). The suture zone between the former island arc complex and the continental margin formed the Main Uralian Fault , a major structure that runs for more than 2,000 km along the orogen. Accretion of the island arc

2548-653: The Old Red Sandstone , Carboniferous Limestone , Millstone Grit and the Coal Measures . These four units were placed into a formalised Carboniferous unit by William Conybeare and William Phillips in 1822 and then into the Carboniferous System by Phillips in 1835. The Old Red Sandstone was later considered Devonian in age. The similarity in successions between the British Isles and Western Europe led to

2639-460: The orchids for part or all of their life-cycle, or on other plants , either wholly like the broomrapes, Orobanche , or partially like the witchweeds, Striga . In terms of their environment, flowering plants are cosmopolitan, occupying a wide range of habitats on land, in fresh water and in the sea. On land, they are the dominant plant group in every habitat except for frigid moss-lichen tundra and coniferous forest . The seagrasses in

2730-883: The "Big Five" extinction events in Earth's history, only the Cretaceous–Paleogene extinction event had occurred while angiosperms dominated plant life on the planet. Today, the Holocene extinction affects all kingdoms of complex life on Earth, and conservation measures are necessary to protect plants in their habitats in the wild ( in situ ), or failing that, ex situ in seed banks or artificial habitats like botanic gardens . Otherwise, around 40% of plant species may become extinct due to human actions such as habitat destruction , introduction of invasive species , unsustainable logging , land clearing and overharvesting of medicinal or ornamental plants . Further, climate change

2821-747: The 1840s British and Russian geologists divided the Carboniferous into the Lower, Middle and Upper series based on Russian sequences. In the 1890s these became the Dinantian, Moscovian and Uralian stages. The Serpukivian was proposed as part of the Lower Carboniferous, and the Upper Carboniferous was divided into the Moscovian and Gzhelian . The Bashkirian was added in 1934. In 1975, the ICS formally ratified

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2912-520: The Bashkirian, the late Moscovian and the latest Kasimovian to mid-Gzhelian are inferred from the disappearance of glacial sediments, the appearance of deglaciation deposits and rises in sea levels. In the early Kasimovian there was short-lived (<1 million years) intense period of glaciation, with atmospheric CO 2 concentration levels dropping as low as 180 ppm. This ended suddenly as a rapid increase in CO 2 concentrations to c. 600 ppm resulted in

3003-726: The Carboniferous Earth's atmosphere, and the coal fueled the Industrial Revolution . During the Pennsylvanian, vast amounts of organic debris accumulated in the peat mires that formed across the low-lying, humid equatorial wetlands of the foreland basins of the Central Pangean Mountains in Laurussia, and around the margins of the North and South China cratons. During glacial periods, low sea levels exposed large areas of

3094-641: The Carboniferous System, with the Mississippian and Pennsylvanian subsystems from the North American timescale, the Tournaisian and Visean stages from the Western European and the Serpukhovian, Bashkirian, Moscovian, Kasimovian and Gzhelian from the Russian. With the formal ratification of the Carboniferous System, the Dinantian, Silesian, Namurian, Westphalian and Stephanian became redundant terms, although

3185-591: The Carboniferous, the Tarim craton lay along the northwestern edge of North China. Subduction along the Kazakhstanian margin of the Turkestan Ocean resulted in collision between northern Tarim and Kazakhstania during the mid Carboniferous as the ocean closed. The South Tian Shan fold and thrust belt , which extends over 2,000 km from Uzbekistan to northwest China, is the remains of this accretionary complex and forms

3276-725: The Early Mississippian, led to the rifting of the Yukon-Tanana terrane and the opening of the Slide Mountain Ocean . Along the northern margin of Laurussia, orogenic collapse of the Late Devonian to Early Mississippian Innuitian orogeny led to the development of the Sverdrup Basin . Much of Gondwana lay in the southern polar region during the Carboniferous. As the plate moved, the South Pole drifted from southern Africa in

3367-509: The Early to Middle Mississippian, carbonate production occurred to depth across the gently dipping continental slopes of Laurussia and North and South China ( carbonate ramp architecture) and evaporites formed around the coastal regions of Laurussia, Kazakhstania, and northern Gondwana. From the late Visean, the cooling climate restricted carbonate production to depths of less than c. 10 m forming carbonate shelves with flat-tops and steep sides. By

3458-485: The Kasimovian covers a period of globally low sea level, which has resulted in disconformities within many sequences of this age. This has created difficulties in finding suitable marine fauna that can used to correlate boundaries worldwide. The Kasimovian currently lacks a defined GSSP; potential sites in the southern Urals, southwest USA and Nashui, Guizhou Province, southwestern China are being considered. The Gzhelian

3549-476: The Late Ordovician . As they drifted northwards the Rheic Ocean closed in front of them, and they began to collide with southeastern Laurussia in the Middle Devonian. The resulting Variscan orogeny involved a complex series of oblique collisions with associated metamorphism , igneous activity, and large-scale deformation between these terranes and Laurussia, which continued into the Carboniferous. During

3640-635: The Late Pennsylvanian, deformation along the Alleghanian orogen became northwesterly-directed compression . The Uralian orogeny is a north–south trending fold and thrust belt that forms the western edge of the Central Asian Orogenic Belt . The Uralian orogeny began in the Late Devonian and continued, with some hiatuses, into the Jurassic . From the Late Devonian to early Carboniferous,

3731-615: The Paleo-Tethys to the southwest and Panthalassa to the northeast. Cyclothem sediments with coal and evaporites were deposited across the passive margins that surrounded both continents. The Carboniferous climate was dominated by the Late Paleozoic Ice Age (LPIA), the most extensive and longest icehouse period of the Phanerozoic, which lasted from the Late Devonian to the Permian (365 Ma-253 Ma). Temperatures began to drop during

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3822-459: The Pennsylvanian, cyclothems were deposited in shallow, epicontinental seas across the tropical regions of Laurussia (present day western and central US, Europe, Russia and central Asia) and the North and South China cratons . The rapid sea levels fluctuations they represent correlate with the glacial cycles of the Late Paleozoic Ice Age. The advance and retreat of ice sheets across Gondwana followed

3913-402: The Pennsylvanian, together with widespread glaciation across Gondwana led to major climate and sea level changes, which restricted marine fauna to particular geographic areas thereby reducing widespread biostratigraphic correlations. Extensive volcanic events associated with the assembling of Pangea means more radiometric dating is possible relative to the Mississippian. The Bashkirian Stage

4004-475: The Period. This was not a steady rise, but included peaks and troughs reflecting the dynamic climate conditions of the time. How the atmospheric oxygen concentrations influenced the large body size of arthropods and other fauna and flora during the Carboniferous is also a subject of ongoing debate. The changing climate was reflected in regional-scale changes in sedimentation patterns. In the relatively warm waters of

4095-480: The Permian. The Kazakhstanian microcontinent is composed of a series of Devonian and older accretionary complexes. It was strongly deformed during the Carboniferous as its western margin collided with Laurussia during the Uralian orogen and its northeastern margin collided with Siberia. Continuing strike-slip motion between Laurussia and Siberia led the formerly elongate microcontinent to bend into an orocline . During

4186-542: The Urals and Nashui, Guizhou Province, southwestern China are being considered. The Kasimovian is the first stage in the Upper Pennsylvanian. It is named after the Russian city of Kasimov , and was originally included as part of Nikitin's 1890 definition of the Moscovian. It was first recognised as a distinct unit by A.P. Ivanov in 1926, who named it the " Tiguliferina " Horizon after a type of brachiopod . The boundary of

4277-490: The Urals and Nashui, Guizhou Province, southwestern China for the GSSP are being considered. The GSSP for the base of the Permian is located in the Aidaralash River valley near Aqtöbe , Kazakhstan and was ratified in 1996. The beginning of the stage is defined by the first appearance of the conodont Streptognathodus postfusus . A cyclothem is a succession of non-marine and marine sedimentary rocks , deposited during

4368-463: The Visean of c. 15.3%, although with large uncertainties; and, pyrite records suggest levels of c. 15% early in the Carboniferous, to over 25% during the Pennsylvanian, before dropping back below 20% towards the end. However, whilst exact numbers vary, all models show an overall increase in atmospheric oxygen levels from a low of between 15-20% at the beginning of the Carboniferous to highs of 25-30% during

4459-511: The Zharma-Saur arc formed along the northeastern margin of Kazakhstania. By the late Carboniferous, all these complexes had accreted to the Siberian craton as shown by the intrusion of post-orogenic granites across the region. As Kazakhstania had already accreted to Laurussia, Siberia was effectively part of Pangea by 310 Ma, although major strike-slip movements continued between it and Laurussia into

4550-647: The average temperature in the tropics c. 24 °C (75 °F) and in polar regions c. -23 °C (-10 °F), whilst during the Early Tournaisian Warm Interval (358-353 Ma) the GAT was c. 22 °C (72 °F), the tropics c. 30 °C (86 °F) and polar regions c. 1.5 °C (35 °F). Overall, for the Ice Age the GAT was c. 17 °C (62 °F), with tropical temperatures c. 26 °C and polar temperatures c. -9.0 °C (16 °F). There are

4641-516: The base of the Carboniferous System, Mississippian Subsystem and Tournaisian Stage is located at the La Serre section in Montagne Noire , southern France. It is defined by the first appearance of the conodont Siphonodella sulcata within the evolutionary lineage from Siphonodella praesulcata to Siphonodella sulcata . This was ratified by the ICS in 1990. However, in 2006 further study revealed

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4732-433: The beginning of the Period to highs of 25-30%. The development of a Carboniferous chronostratigraphic timescale began in the late 18th century. The term "Carboniferous" was first used as an adjective by Irish geologist Richard Kirwan in 1799 and later used in a heading entitled "Coal-measures or Carboniferous Strata" by John Farey Sr. in 1811. Four units were originally ascribed to the Carboniferous, in ascending order,

4823-410: The charcoal record and pyrite). Results from these different methods for the Carboniferous vary. For example: the increasing occurrence of charcoal produced by wildfires from the Late Devonian into the Carboniferous indicates increasing oxygen levels, with calculations showing oxygen levels above 21% for most of the Carboniferous; halite gas inclusions from sediments dated 337-335 Ma give estimates for

4914-562: The city of Visé , Liège Province , Belgium. In 1967, the base of the Visean was officially defined as the first black limestone in the Leffe facies at the Bastion Section in the Dinant Basin . These changes are now thought to be ecologically driven rather than caused by evolutionary change, and so this has not been used as the location for the GSSP. Instead, the GSSP for the base of the Visean

5005-547: The common ancestor of all living gymnosperms before the end of the Carboniferous , over 300 million years ago. In the Cretaceous , angiosperms diversified explosively , becoming the dominant group of plants across the planet. Agriculture is almost entirely dependent on angiosperms, and a small number of flowering plant families supply nearly all plant-based food and livestock feed. Rice , maize and wheat provide half of

5096-465: The complexity of the geology. The ICS subdivisions from youngest to oldest are as follows: The Mississippian was proposed by Alexander Winchell in 1870 named after the extensive exposure of lower Carboniferous limestone in the upper Mississippi River valley. During the Mississippian, there was a marine connection between the Paleo-Tethys and Panthalassa through the Rheic Ocean resulting in

5187-437: The continental shelves. Major river channels, up to several kilometres wide, stretched across these shelves feeding a network of smaller channels, lakes and peat mires. These wetlands were then buried by sediment as sea levels rose during interglacials . Continued crustal subsidence of the foreland basins and continental margins allowed this accumulation and burial of peat deposits to continue over millions of years resulting in

5278-510: The development of a common European timescale with the Carboniferous System divided into the lower Dinantian , dominated by carbonate deposition and the upper Silesian with mainly siliciclastic deposition. The Dinantian was divided into the Tournaisian and Viséan stages. The Silesian was divided into the Namurian , Westphalian and Stephanian stages. The Tournaisian is the same length as

5369-475: The early Carboniferous Kanimblan Orogeny . Continental arc magmatism continued into the late Carboniferous and extended round to connect with the developing proto-Andean subduction zone along the western South American margin of Gondwana. Shallow seas covered much of the Siberian craton in the early Carboniferous. These retreated as sea levels fell in the Pennsylvanian and as the continent drifted north into more temperate zones extensive coal deposits formed in

5460-416: The early Carboniferous in North China. However, bauxite deposits immediately above the regional mid Carboniferous unconformity indicate warm tropical conditions and are overlain by cyclothems including extensive coals. South China and Annamia (Southeast Asia) rifted from Gondwana during the Devonian. During the Carboniferous, they were separated from each other and North China by the Paleoasian Ocean with

5551-503: The early Carboniferous to eastern Antarctica by the end of the period. Glacial deposits are widespread across Gondwana and indicate multiple ice centres and long-distance movement of ice. The northern to northeastern margin of Gondwana (northeast Africa, Arabia, India and northeastern West Australia) was a passive margin along the southern edge of the Paleo-Tethys with cyclothem deposition including, during more temperate intervals, coal swamps in Western Australia. The Mexican terranes along

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5642-406: The end of the Carboniferous, extension and rifting across the northern margin of Gondwana led to the breaking away of the Cimmerian Terrane during the early Permian and the opening of the Neo-Tethys Ocean . Along the southeastern and southern margin of Gondwana (eastern Australia and Antarctica), northward subduction of Panthalassa continued. Changes in the relative motion of the plates resulted in

5733-403: The end of the Devonian, even if the specific enzymes used by basidiomycetes had not. The second theory is that the geographical setting and climate of the Carboniferous were unique in Earth's history: the co-occurrence of the position of the continents across the humid equatorial zone, high biological productivity, and the low-lying, water-logged and slowly subsiding sedimentary basins that allowed

5824-422: The flowering plants as an unranked clade without a formal Latin name (angiosperms). A formal classification was published alongside the 2009 revision in which the flowering plants rank as the subclass Magnoliidae. From 1998, the Angiosperm Phylogeny Group (APG) has reclassified the angiosperms, with updates in the APG II system in 2003, the APG III system in 2009, and the APG IV system in 2016. In 2019,

5915-425: The formation of thick and widespread coal formations. During the warm interglacials, smaller coal swamps with plants adapted to the temperate conditions formed on the Siberian craton and the western Australian region of Gondwana. There is ongoing debate as to why this peak in the formation of Earth's coal deposits occurred during the Carboniferous. The first theory, known as the delayed fungal evolution hypothesis,

6006-456: The late Carboniferous. Land arthropods such as arachnids (e.g. trigonotarbids and Pulmonoscorpius ), myriapods (e.g. Arthropleura ) and especially insects (particularly flying insects ) also underwent a major evolutionary radiation during the late Carboniferous. Vast swaths of forests and swamps covered the land, which eventually became the coal beds characteristic of the Carboniferous stratigraphy evident today. The later half of

6097-433: The late Devonian with a short-lived glaciation in the late Famennian through Devonian–Carboniferous boundary, before the Early Tournaisian Warm Interval. Following this, a reduction in atmospheric CO 2 levels, caused by the increased burial of organic matter and widespread ocean anoxia led to climate cooling and glaciation across the south polar region. During the Visean Warm Interval glaciers nearly vanished retreating to

6188-469: The latter three are still in common use in Western Europe. Stages can be defined globally or regionally. For global stratigraphic correlation, the ICS ratify global stages based on a Global Boundary Stratotype Section and Point (GSSP) from a single formation (a stratotype ) identifying the lower boundary of the stage. Only the boundaries of the Carboniferous System and three of the stage bases are defined by global stratotype sections and points because of

6279-432: The majority of a cyclothem sequence occurred during falling sea levels, when rates of erosion were high, meaning they were often periods of non-deposition. Erosion during sea level falls could also result in the full or partial removal of previous cyclothem sequences. Individual cyclothems are generally less than 10 m thick because the speed at which sea level rose gave only limited time for sediments to accumulate. During

6370-518: The manner of vines or lianas . The number of species of flowering plants is estimated to be in the range of 250,000 to 400,000. This compares to around 12,000 species of moss and 11,000 species of pteridophytes . The APG system seeks to determine the number of families , mostly by molecular phylogenetics . In the 2009 APG III there were 415 families. The 2016 APG IV added five new orders (Boraginales, Dilleniales, Icacinales, Metteniusales and Vahliales), along with some new families, for

6461-430: The mid Carboniferous, the South American sector of Gondwana collided obliquely with Laurussia's southern margin resulting in the Ouachita orogeny. The major strike-slip faulting that occurred between Laurussia and Gondwana extended eastwards into the Appalachian Mountains where early deformation in the Alleghanian orogeny was predominantly strike-slip. As the West African sector of Gondwana collided with Laurussia during

6552-451: The near worldwide distribution of marine faunas and so allowing widespread correlations using marine biostratigraphy . However, there are few Mississippian volcanic rocks , and so obtaining radiometric dates is difficult. The Tournaisian Stage is named after the Belgian city of Tournai . It was introduced in scientific literature by Belgian geologist André Dumont in 1832. The GSSP for

6643-556: The northwestern Gondwana margin, were affected by the subduction of the Rheic Ocean. However, they lay to west of the Ouachita orogeny and were not impacted by continental collision but became part of the active margin of the Pacific. The Moroccan margin was affected by periods of widespread dextral strike-slip deformation, magmatism and metamorphism associated with the Variscan orogeny. Towards

6734-426: The peat mires. As fully marine conditions were established, limestones succeeded these marginal marine deposits. The limestones were in turn overlain by deep water black shales as maximum sea levels were reached. Ideally, this sequence would be reversed as sea levels began to fall again; however, sea level falls tend to be protracted, whilst sea level rises are rapid, ice sheets grow slowly but melt quickly. Therefore,

6825-454: The period experienced glaciations , low sea level, and mountain building as the continents collided to form Pangaea . A minor marine and terrestrial extinction event, the Carboniferous rainforest collapse , occurred at the end of the period, caused by climate change. Atmospheric oxygen levels, originally thought to be consistently higher than today throughout the Carboniferous, have been shown to be more variable, increasing from low levels at

6916-488: The preceding Devonian period, became pentadactylous during the Carboniferous. The period is sometimes called the Age of Amphibians because of the diversification of early amphibians such as the temnospondyls , which became dominant land vertebrates, as well as the first appearance of amniotes including synapsids (the clade to which modern mammals belong) and sauropsids (which include modern reptiles and birds) during

7007-459: The presence of Siphonodella sulcata below the boundary, and the presence of Siphonodella praesulcata and Siphonodella sulcata together above a local unconformity . This means the evolution of one species to the other, the definition of the boundary, is not seen at the La Serre site making precise correlation difficult. The Viséan Stage was introduced by André Dumont in 1832 and is named after

7098-877: The proto-Andes in Bolivia and western Argentina and the Pan-African mountain ranges in southeastern Brazil and southwest Africa. The main phase of the LPIA (c. 335-290 Ma) began in the late Visean, as the climate cooled and atmospheric CO 2 levels dropped. Its onset was accompanied by a global fall in sea level and widespread multimillion-year unconformities. This main phase consisted of a series of discrete several million-year-long glacial periods during which ice expanded out from up to 30 ice centres that stretched across mid- to high latitudes of Gondwana in eastern Australia, northwestern Argentina, southern Brazil, and central and Southern Africa. Isotope records indicate this drop in CO 2 levels

7189-622: The sea. Cyclothem lithologies vary from mudrock and carbonate-dominated to coarse siliciclastic sediment-dominated sequences depending on the paleo-topography, climate and supply of sediments to the shelf. The main period of cyclothem deposition occurred during the Late Paleozoic Ice Age from the Late Mississippian to early Permian, when the waxing and waning of ice sheets led to rapid changes in eustatic sea level . The growth of ice sheets led global sea levels to fall as water

7280-568: The spring gentian, are adapted to the alkaline conditions found on calcium -rich chalk and limestone , which give rise to often dry topographies such as limestone pavement . As for their growth habit , the flowering plants range from small, soft herbaceous plants , often living as annuals or biennials that set seed and die after one growing season, to large perennial woody trees that may live for many centuries and grow to many metres in height. Some species grow tall without being self-supporting like trees by climbing on other plants in

7371-556: The suture between Kazakhstania and Tarim. A continental magmatic arc above a south-dipping subduction zone lay along the northern North China margin, consuming the Paleoasian Ocean. Northward subduction of the Paleo-Tethys beneath the southern margins of North China and Tarim continued during the Carboniferous, with the South Qinling block accreted to North China during the mid to late Carboniferous. No sediments are preserved from

7462-410: The thick accumulation of peat were sufficient to account for the peak in coal formation. During the Carboniferous, there was an increased rate in tectonic plate movements as the supercontinent Pangea assembled. The continents themselves formed a near circle around the opening Paleo-Tethys Ocean, with the massive Panthalassic Ocean beyond. Gondwana covered the south polar region. To its northwest

7553-544: The uplift and erosion of the more mafic basement rocks of the Central Pangea Mountains at this time, CO 2 levels dropped as low as 175 ppm and remained under 400 ppm for 10 Ma. Temperatures across the Carboniferous reflect the phases of the LPIA. At the extremes, during the Permo-Carboniferous Glacial Maximum (299-293 Ma) the global average temperature (GAT) was c. 13 °C (55 °F),

7644-554: The world's staple calorie intake, and all three plants are cereals from the Poaceae family (colloquially known as grasses). Other families provide important industrial plant products such as wood , paper and cotton , and supply numerous ingredients for beverages , sugar production , traditional medicine and modern pharmaceuticals . Flowering plants are also commonly grown for decorative purposes , with certain flowers playing significant cultural roles in many societies. Out of

7735-487: Was Laurussia. These two continents slowly collided to form the core of Pangea. To the north of Laurussia lay Siberia and Amuria . To the east of Siberia, Kazakhstania , North China and South China formed the northern margin of the Paleo-Tethys, with Annamia laying to the south. The Central Pangean Mountains were formed during the Variscan - Alleghanian - Ouachita orogeny. Today their remains stretch over 10,000 km from

7826-483: Was coined in the form "Angiospermae" by Paul Hermann in 1690, including only flowering plants whose seeds were enclosed in capsules. The term angiosperm fundamentally changed in meaning in 1827 with Robert Brown , when angiosperm came to mean a seed plant with enclosed ovules. In 1851, with Wilhelm Hofmeister 's work on embryo-sacs, Angiosperm came to have its modern meaning of all the flowering plants including Dicotyledons and Monocotyledons. The APG system treats

7917-500: Was complete by the Tournaisian, but subduction of the Ural Ocean between Kazakhstania and Laurussia continued until the Bashkirian when the ocean finally closed and continental collision began. Significant strike-slip movement along this zone indicates the collision was oblique. Deformation continued into the Permian and during the late Carboniferous and Permian the region was extensively intruded by granites . The Laurussian continent

8008-559: Was formed by the collision between Laurentia , Baltica and Avalonia during the Devonian. At the beginning of the Carboniferous, some models show it at the equator, whilst others place it further south. In either case, the continent drifted northwards, reaching low latitudes in the northern hemisphere by the end of the Period. The Central Pangean Mountain drew in moist air from the Paleo-Tethys Ocean resulting in heavy precipitation and

8099-646: Was lock away in glaciers. Falling sea levels exposed large tracts of the continental shelves across which river systems eroded channels and valleys and vegetation broke down the surface to form soils . The non-marine sediments deposited on this erosional surface form the base of the cyclothem. As sea levels began to rise, the rivers flowed through increasingly water-logged landscapes of swamps and lakes. Peat mires developed in these wet and oxygen-poor conditions, leading to coal formation. With continuing sea level rise, coastlines migrated landward and deltas , lagoons and esturaries developed; their sediments deposited over

8190-564: Was proposed by Russian stratigrapher Sofia Semikhatova in 1934. It was named after Bashkiria , the then Russian name of the republic of Bashkortostan in the southern Ural Mountains of Russia. The GSSP for the base of the Pennsylvanian Subsystem and Bashkirian Stage is located at Arrow Canyon in Nevada , US and was ratified in 1996. It is defined by the first appearance of the conodont Declinognathodus noduliferus . Arrow Canyon lay in

8281-455: Was triggered by tectonic factors with increased weathering of the growing Central Pangean Mountains and the influence of the mountains on precipitation and surface water flow. Closure of the oceanic gateway between the Rheic and Tethys oceans in the early Bashkirian also contributed to climate cooling by changing ocean circulation and heat flow patterns. Warmer periods with reduced ice volume within

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