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48-501: It altered the vast coal forests that covered the equatorial region of Euramerica (Europe and North 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. In

96-477: A forest-independent life, and fossil records of both large griffinflies and Arthropleura are known after rainforest collapse. This means that rainforest collapse and reduced oxygen levels were less involved in their extinction. The sudden collapse affected several large groups. Labyrinthodont amphibians were particularly devastated, while the amniotes (the first members of the sauropsid and synapsid groups) fared better, being physiologically better adapted to

144-741: A limited capacity to adapt to the drier conditions that dominated Permian environments, many amphibian families failed to occupy new ecological niches and became extinct. Amphibians also removed the scales of their aquatic ancestors , and breathed with both lungs and skin (as long as the skin was kept wet). But amniotes re-evolved scales, now more keratinized, allowing them to conserve water but losing their cutaneous respiration . Synapsids and sauropsids acquired new niches faster than amphibians, and new feeding strategies, including herbivory and carnivory , previously only having been insectivores and piscivores . Synapsids in particular became substantially larger than before and this trend would continue until

192-572: A longstanding refugium, based on the discovery of the "living fossil" of a marine dinoflagellate called Dapsilidinium pastielsii , currently found in the Indo-Pacific Warm Pool only. For plants, anthropogenic climate change propels scientific interest in identifying refugial species that were isolated into small or disjunct ranges during glacial episodes of the Pleistocene , yet whose ability to expand their ranges during

240-492: A measure of geodiversity. Because geodiversity has been shown to be correlated with biodiversity, even as species move in response to climate change, protected areas with high geodiversity may continue to protect biodiversity as niches get filled by the influx of species from neighboring areas. Highly geodiverse protected areas may also allow for the movement of species within the area from one land facet or elevation to another. Conservation scientists, however, emphasize that

288-419: A meteor strike, and global, multiyear effects occur. The sweepstake-winning species happens to already be living in a fortunate site, and their environment is rendered even more advantageous, as opposed to the "losing" species, which immediately fails to reproduce. Ecological understanding and geographic identification of climate refugia that remained significant strongholds for plant and animal survival during

336-620: A shift in the overall regional climate to drier conditions in the Upper Pennsylvanian (Missourian). This is consistent with climate interpretations based on contemporaneous paleo-floral assemblages and geological evidence. At the time of the Carboniferous rainforest collapse, the climate became cooler and drier. This is reflected in the rock record as the Earth entered a short, intense ice age. Sea levels dropped by about 100 metres (330 ft), and glacial ice covered most of

384-553: A species inhabits during the period of a glacial/interglacial cycle that represents the species' maximum contraction in geographical range," and "areas where local populations of a species can persist through periods of unfavorable regional climate." In systematic conservation planning , the term refugium has been used to define areas that could be used in protected area development to protect species from climate change . The term has been used alternatively to refer to areas with stable habitats or stable climates. More specifically,

432-415: A wide area but only for a small part of the coal-forming period, and are thus useful as zone fossils . Animals inhabiting the coal forests were invertebrates (particularly insects), fish, labyrinthodont amphibians, and early reptiles. Amphibians were widespread, but once the coal forests fragmented, the new environment was better suited to reptiles, which became more diverse and even varied their diet in

480-435: Is characterised by the formation of coal deposits which were formed within a context of the removal of atmospheric carbon. In the latest Middle Pennsylvanian (late Moscovian) a cycle of aridification began, coinciding with abrupt faunal changes in marine and terrestrial species. This change was recorded in paleosols , which reflect a period of overall decreased hydromorphy , increased free-drainage and landscape stability, and

528-692: Is confirmed by a 2011 study showing that the presence of meandering and anabranching streams, occurrences of large woody debris, and records of log jams decrease significantly at the Moscovian-Kasimovian boundary. Rainforests were fragmented, forming shrinking 'islands' further and further apart, and in latest Kasimovian time, rainforests vanished from the fossil record. Little mixing of different plant assemblages occurred throughout this transition; floral assemblages were highly discrete and conservative and gave way to new ones without any transitional floras intermediate in composition with regards to

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576-534: Is sometimes treated as an extinction factor for large Carboniferous arthropods such as giant griffinfly Meganeura and millipede Arthropleura . It is common theory that high oxygen levels have led to larger arthropods, and these organisms have been thought to live in forests. It was said that rainforest collapse led to a decrease in oxygen concentration and a decrease in the habitat of these arthropods, leading them to extinction. However, later study shows that both griffinflies and Arthropleura more likely lived

624-552: The Klamath-Siskiyou Ecoregion found that, in addition to old-growth forest, the northern aspects of hillslopes and deep gorges would provide relatively cool areas for wildlife and seeps or bogs surrounded by mature and old-growth forests would continue to supply moisture even as water availability decreases. Beginning in 2010 the concept of geodiversity (a term used previously in efforts to preserve scientifically important geological features) entered into

672-542: The Last Glacial Maximum ) in sparsely wooded areas and dispersed through areas of high primary productivity while avoiding dense forest cover . Glacial refugia, where human populations found refuge during the last glacial period, may have played a crucial role in shaping the emergence and diversification of the language families that exist in the world today. More recently, refugia has been used to refer to areas that could offer relative climate stability in

720-568: The mountain gorilla , isolated to specific mountains in central Africa, and the Australian sea lion , isolated to specific breeding beaches along the south-west coast of Australia, due to humans taking so many of their number as game. This resulting isolation, in many cases, can be seen as only a temporary state; however, some refugia may be longstanding, thereby having many endemic species , not found elsewhere, which survive as relict populations. The Indo-Pacific Warm Pool has been proposed to be

768-411: The southern hemisphere .) Each site becomes a refugium, one as a "cold-surviving refugium" and the other as a "hot-surviving refugium". Canyons with deep hidden areas (the opposite of hillsides, mountains, mesas, etc. or other exposed areas) lead to these separate types of refugia. A concept not often referenced is that of "sweepstakes colonization": when a dramatic ecological event occurs, for example

816-597: The Carboniferous, the great tropical rainforests of Euramerica supported towering lycopodiophyta , a heterogeneous mix of vegetation, as well as a great diversity of animal life: giant griffinflies , millipedes , blattopterans , smaller amphibians, and the first amniotes . The rise of rainforests in the Carboniferous greatly altered the landscapes by eroding low-energy, organic-rich anastomosing (braided) river systems with multiple channels and stable alluvial islands. The continuing evolution of tree-like plants increased floodplain stability (less erosion and movement) by

864-578: The Moskovian/Kasimovian boundary and the Carboniferous rainforest collapse. While the CRC affected the equatorial region of Euramerica, the collapse had no effect in the region of Cathaysia to the east (which mostly corresponds to modern China), where Carboniferous-like rainforests persisted until the end of the Permian, around 252 million years ago. Many fossil sites around the world reflect

912-776: The Pennsylvanian and early Permian . As the climate aridified through the Late Paleozoic, rainforests were eventually replaced by seasonally dry biomes. After restoring the middle of the Skagerrak-Centered Large Igneous Province using a new reference frame, it has been shown that the Skagerrak plume rose from the core–mantle boundary to its ~300 Ma position. The major eruption interval took place in very narrow time interval, of 297 Ma ± 4 Ma. The rift formation coincides with

960-601: The Permian–Triassic extinction event, after which their cynodont ( mammal ancestors) descendants became smaller and nocturnal . There are several hypotheses about the nature and cause of the Carboniferous rainforest collapse, some of which include climate change . After the late Bashkirian glacial maximum of the Late Paleozoic Ice Age  I, around 318  Ma , frequent shifts in seasonality from humid to arid times began. The Carboniferous period

1008-511: The ancestors of reptiles and mammals diversified into more species after the initial crisis. These patterns are explained by the theory of insular biogeography , a concept that explains how evolution progresses when populations are restricted into isolated pockets. This theory was originally developed for oceanic islands , but it can be applied equally well to any other ecosystem that is fragmented, only existing in small patches and surrounded by another unsuitable habitat. According to this theory,

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1056-540: The area may have been a refugium. Moreover, the current distribution of species with narrow ecological requirements tend to be associated with the spatial position of glacial refugia. One can provide a simple explanation of refugia involving core temperatures and exposure to sunlight. In the northern hemisphere , north-facing sites on hills or mountains, and places at higher elevations count as cold sites . The reverse are sun- or heat-exposed, lower-elevation, south-facing sites: hot sites . (The opposite directions apply in

1104-476: The changing conditions of the Carboniferous rainforest collapse. The Joggins Fossil Cliffs on Nova Scotia's Bay of Fundy , a UNESCO World Heritage Site, is a particularly well-preserved fossil site. Fossil skeletons embedded in the crumbling sea cliffs were discovered by Sir Charles Lyell in 1852. In 1859, his colleague William Dawson discovered the oldest known reptile-ancestor, Hylonomus lyelli , and since then hundreds more skeletons have been found, including

1152-440: The coal forests in very late Carboniferous seems to have coincided with a lowering of global temperatures and a return of extensive polar ice in southern Gondwana , perhaps caused by lessening of the greenhouse effect as the massive coal deposition process extracted carbon dioxide from the atmosphere. The coal forests seem to have been areas of flat, low-lying swampy areas with rivers flowing through from higher, drier land. When

1200-614: The coast are predicted to experience overall less warming than areas toward the interior of the US State of Washington . Other research has found that old-growth forests are particularly insulated from climatic changes due to evaporative cooling effects from evapotranspiration and their ability to retain moisture. The same study found that such effects in the Pacific Northwest would create important refugia for bird species. A review of refugia-focused conservation strategy in

1248-643: The demise of Carboniferous rainforests. The fragmentation of wetlands left a few isolated refugia in Europe. However, even these were unable to maintain the diversity of Moscovian flora. By the Asselian , many families of seed ferns that characterized the Moscovian tropical wetlands had disappeared including Flemingitaceae , Diaphorodendraceae , Tedeleaceae , Urnatopteridaceae , Cyclopteridaceae , and Neurodontopteridaceae . Carboniferous rainforest collapse

1296-437: The density of floodplain forests, the production of woody debris, and an increase in complexity and diversity of root assemblages. Collapse occurred through a series of step changes. First there was a gradual rise in the frequency of opportunistic ferns in late Moscovian times. This was followed in the earliest Kasimovian by a major, abrupt extinction of the dominant lycopsids and a change to tree fern -dominated ecosystems. This

1344-486: The drier conditions. Amphibians can survive cold conditions by decreasing metabolic rates and resorting to overwintering strategies (i.e. spending most of the year inactive in burrows or under logs). However, this is not an effective way to deal with prolonged unfavourable conditions, especially desiccation . Amphibians must return to water to lay eggs, while amniotes have eggs that have a membrane that retains water and allows gas exchange out of water. Because amphibians had

1392-472: The edges of lakes and waterways. Lycopsid genera specialized in various roles: Paralycopodites as a pioneer on newly silted lakes shallow enough for land vegetation to start; Diaphorodendron later when the ground had become peaty. Other species specialized in re-settling land which had been briefly deforested by flooding: Synchysidendron and Lepidodendron in mineral-soil areas and Lepidophloios in peat areas. Cordaites may have favored drier areas of

1440-597: The extremes of past cooling and warming episodes largely pertain to the Quaternary glaciation cycles during the past several million years, especially in the Northern Hemisphere . A number of defining characteristics of past refugia are prevalent, including "an area where distinct genetic lineages have persisted through a series of Tertiary or Quaternary climate fluctuations owing to special, buffering environmental characteristics", "a geographical region that

1488-483: The face of modern climate change . As an example of a locale refugia study, Jürgen Haffer first proposed the concept of refugia to explain the biological diversity of bird populations in the Amazonian river basin . Haffer suggested that climatic change in the late Pleistocene led to reduced reservoirs of habitable forests in which populations become allopatric. Over time, that led to speciation : populations of

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1536-659: The face of the continental ice sheets ) during the last glacial period . Going from west to east, suggested examples include the Franco-Cantabrian region (in northern Iberia ), the Italian and Balkan peninsulas, the Ukrainian LGM refuge , and the Bering Land Bridge . Archaeological and genetic data suggest that the source populations of Paleolithic humans survived the glacial maxima (including

1584-543: The initial impact of habitat fragmentation is devastating, with most life dying out quickly from lack of resources. Then, as surviving plants and animals reestablish themselves, they adapt to their restricted environment to take advantage of the new allotment of resources, and diversify. After the CRC, each pocket of life evolved in its own way, resulting in a unique species mix that ecologists call " endemism ". A 2018 paper challenged this theory, however, finding evidence for increased cosmopolitanism rather than endemism following

1632-409: The late 1990s and early 2000s. The most recent efforts have used the idea of land facets (also referred to as geophysical settings , enduring features , or geophysical stages ), which are unique combinations of topographical features (such as slope steepness, slope direction, and elevation ) and soil composition, to quantify physical features. The density of these facets, in turn, is used as

1680-659: The literature of conservation biologists as a potential way to identify climate change refugia and as a surrogate (in other words, a proxy used when planning for protected areas) for biodiversity. While the language to describe this mode of conservation planning hadn't fully developed until recently, the use of geophysical diversity in conservation planning goes back at least as far as the work by Hunter and others in 1988, and Richard Cowling and his colleagues in South Africa also used "spatial features" as surrogates for ecological processes in establishing conservation areas in

1728-439: The oldest synapsid, Protoclepsydrops . Coal forest Coal forests were the vast swathes of freshwater swamp and riparian forests that covered much of the lands on Earth's tropical regions during the late Carboniferous ( Pennsylvanian ) and Permian periods. As plant matters from these wetland forests decayed, enormous deposits of peat accumulated, which later became buried and converted into coal over

1776-529: The preceding one and succeeding one. The fossil record of insects can be difficult to study, due to the generally smaller and more delicate nature of their bodies. One study tabulate the rates of origination and extinction of over 600 terrestrial and freshwater animal families. Their stratigraphic ranges spanned a geologic interval from the middle Paleozoic biotic invasion of the land to the Permian–Triassic extinction event . Insects comprise more than half of

1824-464: The rapidly changing environment. These films and TV series are set partly in coal forests: Refugium (population biology) In biology, a refugium (plural: refugia ) is a location which supports an isolated or relict population of a once more widespread species. This isolation ( allopatry ) can be due to climatic changes, geography, or human activities such as deforestation and overhunting. Present examples of refugial animal species are

1872-614: The rest of Carboniferous times, the coal forests were mainly restricted to refugia in North America (such as the Appalachian and Illinois coal basins) and central Europe. At the very end of the Carboniferous, the coal forests underwent a resurgence, expanding mainly in eastern Asia, notably China; they never recovered fully in Laurasia. The Chinese coal forests continued to flourish well into Permian times. This resurgence of

1920-573: The rivers flooded, silt gradually built up into natural levees . Lakes formed as some areas subsided, while formerly wet areas became dry from silt buildups. When a forested area became dry enough to be set on fire by lightning, the resulting forest fire left charcoal , the fusain component of coal. There seems to have been a rich and varied flora, with sets of species for each type of growing condition. The most varied flora seems to have been leafy vegetation, with many species of trees, bushes, creepers, etc. Thickets of Calamites seem to have favored

1968-643: The same species that found themselves in different refugia evolved differently, creating parapatric sister-species . As the Pleistocene ended, the arid conditions gave way to the present humid rainforest environment, reconnecting the refugia. Scholars have since expanded the idea of this mode of speciation and used it to explain population patterns in other areas of the world, such as Africa , Eurasia , and North America . Theoretically, current biogeographical patterns can be used to infer past refugia: if several unrelated species follow concurrent range patterns,

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2016-500: The sampled families, most of which are from tropical Euramerica. This study found a Late Pennsylvanian extinction pulse that reflects drying climates and the transition of lycopod to tree fern-dominated land floras. Before the collapse, vertebrate animal species distribution was very cosmopolitan, with the same species existing across tropical Pangaea . After the collapse, each surviving rainforest 'island' developed its own unique mix of species. Many amphibian species became extinct, while

2064-440: The size of Meganeura compared to modern dragonflies . Coal forests covered tropical Laurasia (Europe, eastern North America, northwesternmost Africa) and Cathaysia (mainly China). Climate change devastated these tropical rainforests during the Carboniferous period. The Carboniferous rainforest collapse was caused by a cooler drier climate that initially fragmented, then collapsed the rainforest ecosystem. During most of

2112-405: The southern continent of Gondwana . The climate was unfavourable to rainforests and much of the biodiversity in them. Rainforests shrank into isolated patches mostly confined to wet valleys further and further apart. Little of the original lycopsid rainforest biome survived this initial climate crisis. The concentration of carbon dioxide in the atmosphere crashed to one of its all time global lows in

2160-451: The subsequent geologic eras. Much of the carbon in the peat deposits produced by coal forests came from photosynthetic fixation of atmospheric carbon dioxide , which released the accompanying split-off oxygen into the atmosphere. This process may have greatly increased the atmospheric concentration of oxygen to possibly as high as about 35%, making the air more breathable by animals with inefficient respiratory systems, as indicated by

2208-572: The swamp. In the later part of this period tree ferns tended to take over from lycopsid trees. Some of the characteristic plants of the coal forests were: Genera recorded in Great Britain include: Palaeontologists have described many species for some of these genera, e.g. (in Britain): Sigillaria 33, Lepidodendron 19, Alethopteris (pteridosperm leaves) 11, Calamites 8. Some easily identified species occur over

2256-495: The term in situ refugium is used to refer to areas that will allow species that exist in an area to remain there even as conditions change, whereas ex situ refugium refers to an area into which species distributions can move to in response to climate change. Sites that offer in situ refugia are also called resilient sites in which species will continue to have what they need to survive even as climate changes. One study found with downscaled climate models that areas near

2304-596: The warmth of interglacial periods (such as the Holocene ) was apparently limited or precluded by topographic , streamflow , or habitat barriers —or by the extinction of coevolved animal dispersers . The concern is that ongoing warming trends will expose them to extirpation or extinction in the decades ahead. In anthropology , refugia often refers specifically to Last Glacial Maximum refugia , where some ancestral human populations may have been forced back to glacial refugia (similar small isolated pockets on

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