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62-616: The Guadalupian is the second and middle series or epoch of the Permian. Previously called Middle Permian, the name of this epoch is part of a revision of Permian stratigraphy for standard global correlation. The name "Guadalupian" was first proposed in the early 1900s, and approved by the International Subcommission on Permian Stratigraphy in 1996. References to the Middle Permian still exist. The Guadalupian

124-683: A mountain range located in West Texas and southeastern New Mexico . The range includes the highest summit in Texas, Guadalupe Peak , 8,751 ft (2,667 m), and the "signature peak" of West Texas, El Capitan , both of which are located within Guadalupe Mountains National Park . The Guadalupe Mountains are bordered by the Pecos River valley and Llano Estacado to the east and north, Delaware Mountains to

186-498: A cultural museum. In 1908, Williams Ranch House was built, and it was named after one of its inhabitants, James Adolphus Williams. Judge J.C. Hunter from Van Horn consolidated most of the smaller ranches in the area into the Guadalupe Mountain Ranch. In 1921, Wallace Pratt , a geologist for Humble Oil and Refining Company , was impressed by the beauty of McKittrick Canyon and bought the land to build two homes in

248-406: A lineage of the eucynodont suborder. Biarmosuchia Dinocephalia Anomodontia Gorgonopsia Therocephalia Cynodontia Six major groups of therapsids are generally recognized: Biarmosuchia , Dinocephalia , Anomodontia , Gorgonopsia , Therocephalia and Cynodontia . A clade uniting therocephalians and cynodonts, called Eutheriodontia , is well supported, but relationships among

310-403: A mutation in the regulatory gene Msx2, which is involved in both the closure of the skull roof and the maintenance of hair follicles in mice. This suggests that hair may have first evolved in probainognathians, though it does not entirely rule out an earlier origin of fur. Whiskers probably evolved in probainognathian cynodonts. Some studies had inferred an earlier origin for whiskers based on

372-517: Is a clade comprising a major group of eupelycosaurian synapsids that includes mammals and their ancestors and close relatives. Many of the traits today seen as unique to mammals had their origin within early therapsids, including limbs that were oriented more underneath the body, resulting in a more "standing" quadrupedal posture, as opposed to the lower sprawling posture of many reptiles and amphibians . Therapsids evolved from earlier synapsids commonly called " pelycosaurs ", specifically within

434-548: Is a favorable environment for photosynthetic organisms and formation of carbonate reefs. As the organisms die and are buried, calcium carbonate incorporated from sea water into shells forms Limestone rock, preserving fossils and their ecology in the rock record. Carbonate production in the Delaware Basin formed the Capitan Reef , one of the most extensive and continuous prehistoric limestone reefs now exposed at

496-587: Is named for these mountains, and the Capitanian age within this epoch is named for the Capitan reef. For details on the area's geology, see Delaware Basin . As the range is built up almost entirely of limestone , upland areas have little or no surface water. The only significant surface water is McKittrick Creek, in McKittrick Canyon, which emerges from the eastern side of the massif, just south of

558-476: Is poorly known, and there are few fossils that provide direct evidence for the presence or absence of fur. The most basal synapsids with unambiguous direct evidence of fur are docodonts , which are mammaliaforms very closely related to crown-group mammals. Two "mummified" juvenile specimens of the dicynodont Lystrosaurus murrayi preserve skin impressions; the skin is hairless, leathery, and dimpled, somewhat comparable to elephant skin. Fossilized facial skin from

620-427: Is poorly understood. Most Permian therapsids had a pineal foramen, indicating that they had a parietal eye like many modern reptiles and amphibians. The parietal eye serves an important role in thermoregulation and the circadian rhythm of ectotherms, but is absent in modern mammals, which are endothermic . Near the end of the Permian, dicynodonts, therocephalians and cynodonts show parallel trends towards loss of

682-401: Is unknown. The climate resembled that of much of central Asia today. Pangea was a supercontinent and had very hot dry summers and cold bitter winters. At this time on the equator there was a desert that reached 74 degrees Celsius. The coasts were tropical and had monsoons. The first two-thirds of the epoch were the continuation of a temperate and tropical climate. This started to dry out and

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744-668: The Basin and Range province , such as the Rio Grande rift west of the Guadalupe Mountains. A mechanism similar to extension in the Rio Grande rift is thought to have generated topographic relief in the Guadalupe Mountains, and the timing of topographic relief generation has been estimated to ~20 million years ago using cave speleothem records and interpreted to reflect drainage of subsurface aquifers as topographic relief

806-629: The Carnian (Late Triassic), although they continued for some time longer in the wet equatorial band and the south. Some exceptions were the still further derived eucynodonts . At least three groups of them survived. They all appeared in the Late Triassic period. The extremely mammal -like family, Tritylodontidae , survived into the Early Cretaceous . Another extremely mammal-like family, Tritheledontidae , are unknown later than

868-477: The Early Cretaceous . Therapsids' temporal fenestrae were larger than those of the pelycosaurs. The jaws of some therapsids were more complex and powerful, and the teeth were differentiated into frontal incisors for nipping, great lateral canines for puncturing and tearing, and molars for shearing and chopping food. Therapsid legs were positioned more vertically beneath their bodies than were

930-591: The Roadian , Wordian , and Capitanian . The Roadian Stage was between 272.3 ± 0.5 – 268.8 ± 0.5 Mya. Olson's Extinction was a worldwide loss of terrestrial vertebrate life that occurred during the Roadian and Wordian. Fauna did not recover fully from Olson's Extinction before the impact of the Permian-Triassic extinction event. Estimates of recovery time vary, where some authors indicated recovery

992-750: The Sphenacodontia , more than 279.5 million years ago. They replaced the pelycosaurs as the dominant large land animals in the Guadalupian through to the Early Triassic. In the aftermath of the Permian–Triassic extinction event , therapsids declined in relative importance to the rapidly diversifying archosaurian sauropsids ( pseudosuchians , dinosaurs and pterosaurs , etc.) during the Middle Triassic. The therapsids include

1054-540: The Theriodontia . Hopson and Barghausen did not initially come to a conclusion about how dinocephalians, anomodonts and theriodonts were related to each other, but subsequent studies suggested that anomodonts and theriodonts should be classified together as the Neotherapsida. However, there remains debate over these relationships; in particular, some studies have suggested that anomodonts, not gorgonopsians, are

1116-631: The cynodonts , the group that gave rise to mammals ( Mammaliaformes ) in the Late Triassic around 225 million years ago, the only therapsid clade that survived beyond the end of the Triassic . The only other group of therapsids to have survived into the Late Triassic , the dicynodonts , became extinct towards the end of the period. The last surviving group of non-mammaliaform cynodonts were the Tritylodontidae , which became extinct during

1178-432: The dinocephalians , the herbivorous anomodonts , the carnivorous biarmosuchians , and the mostly carnivorous theriodonts . After a brief burst of evolutionary diversity, the dinocephalians died out in the later Guadalupian. A mass extinction occurred 273  million years ago in the early Guadalupian before the larger Permian–Triassic extinction event . This extinction was originally called Olson's Gap because it

1240-401: The dinocephalians , the herbivorous anomodonts , the carnivorous biarmosuchians , and the mostly carnivorous theriodonts . After a brief burst of evolutionary diversity, the dinocephalians died out in the later Middle Permian ( Guadalupian ) but the anomodont dicynodonts as well as the theriodont gorgonopsians and therocephalians flourished, being joined at the very end of the Permian by

1302-608: The gorgonopsians among others. A significant mass extinction event (the End-Capitanian extinction event ) occurred at the end of this epoch, which was associated with anoxia and acidification in the oceans and possibly caused by the volcanic eruptions that produced the Emeishan Traps . This extinction event may be related to the much larger Permian–Triassic extinction event that followed about 10 million years later. Carbon isotopes in marine limestone from

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1364-520: The Capitanian Age show an increase in δC values. The change in carbon isotopes in the sea water reflects cooling of global climates . This climatic cooling may have caused the end-Capitanian extinction event among species that lived in warm water, like larger fusulinids (Verbeekninidae), large bivalves ( Alatoconchidae ) and rugose corals, and Waagenophyllidae. Subdivisions that are sometimes used are, Therapsid Therapsida

1426-676: The Early Jurassic . Mammaliaformes was the third group, including Morganucodon and similar animals. Some taxonomists refer to these animals as "mammals", though most limit the term to the mammalian crown group . The non-eucynodont cynodonts survived the Permian–Triassic extinction; Thrinaxodon , Galesaurus and Platycraniellus are known from the Early Triassic . By the Middle Triassic , however, only

1488-597: The Early Permian of the United States has been hypothesized to be an even earlier-diverging therapsid, but more recent study has suggested it is more likely to be a non-therapsid sphenacodontian. Biarmosuchia is the most recently recognized therapsid clade, first recognized as a distinct lineage by Hopson and Barghausen in 1986 and formally named by Sigogneau-Russell in 1989. Most biarmosuchians were previously classified as gorgonopsians. Biarmosuchia includes

1550-541: The Guadalupe Mountains; he worked cattle during the 1870s. McKittrick Canyon is thought to be named after him. Frijole Ranch was the first permanent ranch house; it was constructed in 1876 by the Rader brothers. Frijole Ranch House was the only major building in the region; it served as a community center and regional post office from 1916 to 1942. Today, the Frijole Ranch House has been restored and operates as

1612-753: The New Mexico border. Elevations at the base of the range vary from 4,000 feet (1,200 m) above sea level on the western side to 5,000 feet (1,500 m) on the east. Several peaks on the southern end exceed 8,000 feet (2,400 m). The Guadalupe Mountains experience relatively hot summers, calm, mild autumn weather, and cool to cold weather in winter and early spring. Snow storms, freezing rain, or fog may occur in winter or early spring. Frequent high-wind warnings are issued during winter through spring. Late summer monsoons produce thunderstorms. The nights are cool, even in summer. The Guadalupe Mountains are underlain by Permian aged sedimentary rocks . Although

1674-533: The Sacramento Mountains. The range is bounded on the north by Four Mile Canyon; on the east by the valley of the Pecos River ; and on the west by Piñon Creek, Big Dog Canyon, Valley Canyon, Middle Dog Canyon, and West Dog Canyon. Much of the range is built from the ancient Capitán Reef that formed at the margins of a shallow sea during the Permian period . The Guadalupian epoch of the Permian period

1736-463: The area, and nomadic indigenous tribes of the area such as the Apaches soon found horses to be an asset for hunting and migrating. Mescalero Apaches were nomadic and followed the game and harvested the agave (or mescal) for food and fiber. Mescalero is Spanish for mescal-maker . Agave-roasting pits and other artifacts of Mescalero culture can be found in the park. The Mescalero Apaches remained in

1798-666: The canyon. Both constructions were used as summer homes by Pratt and his family until 1960. Wallace Pratt donated about 6,000 acres (24 km ) of McKittrick Canyon which became part of Guadalupe Mountains National Park . In 1978, the United States Congress designated 46,850 acres (190 km ) of the Texan side of the range as a wilderness area , managed by the National Park Service . The Guadalupe Mountains reach their highest point at Guadalupe Peak,

1860-417: The coal forming of the previous epoch stopped. The change in climate also provided a new environment for new tetrapods, reptiles, fish, plants, and invertebrates. In the last third the temperature started to drop and many coral reefs died out. If that was not enough, increased volcano activity brought a reduction in oxygen, a greenhouse and mass extinction. There are three stages in the guadalupian, they are

1922-499: The dinocephalian Estemmenosuchus has been described as showing that the skin was glandular and lacked both scales and hair. Coprolites containing what appear to be hairs have been found from the Late Permian . Though the source of these hairs is not known with certainty, they may suggest that hair was present in at least some Permian therapsids. The closure of the pineal foramen in probainognathian cynodonts may indicate

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1984-478: The distinctive Burnetiamorpha , but support for the monophyly of Biarmosuchia is relatively low. Many biarmosuchians are known for extensive cranial ornamentation. Dinocephalia comprises two distinctive groups, the Anteosauria and Tapinocephalia . Historically, carnivorous dinocephalians, including both anteosaurs and titanosuchids, were called titanosuchians and classified as members of Theriodontia, while

2046-564: The end-Guadalupian event caused a diversity drop in the Wuchiapingian . There is no agreed cause for the Olson's Extinction. Climate change may be a possible cause. Extreme environments were observed from the Permian of Kansas which resulted from a combination of hot climate and acidic waters particularly coincident with Olson's Extinction. Whether this climate change was a result of Earth's natural processes or exacerbated by another event

2108-438: The eucynodonts remained. The therocephalians , relatives of the cynodonts, managed to survive the Permian–Triassic extinction and continued to diversify through the Early Triassic period. Approaching the end of the period, however, the therocephalians were in decline to eventual extinction, likely outcompeted by the rapidly diversifying Saurian lineage of diapsids , equipped with sophisticated respiratory systems better suited to

2170-471: The first of the cynodonts . Like all land animals, the therapsids were seriously affected by the Permian–Triassic extinction event , with the very successful gorgonopsians and the biarmosuchians dying out altogether and the remaining groups— dicynodonts , therocephalians and cynodonts —reduced to a handful of species each by the earliest Triassic . Surviving dicynodonts were represented by two families of disaster taxa ( Lystrosauridae and Myosauridae ),

2232-631: The herbivorous Tapinocephalidae were classified as members of Anomodontia. Anomodontia includes the dicynodonts , a clade of tusked, beaked herbivores, and the most diverse and long-lived clade of non-cynodont therapsids. Other members of Anomodontia include Suminia , which is thought to have been a climbing form. Gorgonopsia is an abundant but morphologically homogeneous group of saber-toothed predators . It has been suggested that Therocephalia might not be monophyletic, with some species more closely related to cynodonts than others. However, most studies regard Therocephalia as monophyletic. Cynodonts are

2294-553: The highest point in Texas, with an elevation of 8,751 feet (2,667 m). The range lies southeast of the Sacramento Mountains and east of the Brokeoff Mountains. The mountain range extends north-northwest and northeast from Guadalupe Peak in Texas into New Mexico. The northeastern extension ends about 10 miles (16 km) southwest of Carlsbad , near White's City and Carlsbad Caverns National Park ;

2356-675: The land surface. Buried organic matter formed oil and natural gas resources, and ~250,000 wells have been drilled in the surrounding region. Bedrock that formed in shallow oceans of the Delaware Basin were likely uplifted during the Cenozoic period. Subduction of the Farallon Plate underneath the Western United States thickened buoyant continental crust and uplifted the Colorado Plateau across much of

2418-432: The mammaliaform Morganucodon suggest that even early mammaliaforms had reptile-like metabolic rates. Evidence for respiratory turbinates, which have been hypothesized to be indicative of endothermy, was reported in the therocephalian Glanosuchus , but subsequent study showed that the apparent attachment sites for turbinates may simply be the result of distortion of the skull. The evolution of integument in therapsids

2480-481: The many caves and alcoves . The first humans to live here were hunter-gatherers who followed large game and collected edible vegetation. Artifacts that support this include projectile points, baskets, pottery, and rock art. The first Europeans to arrive in the area were the Spaniards in the 16th century, but they did not make serious attempts to settle in the Guadalupe Mountains. The Spanish introduced horses into

2542-537: The most diverse and longest-lived of the therapsid groups, as Cynodontia includes mammals . Cynodonts are the only major therapsid clade to lack a Middle Permian fossil record, with the earliest-known cynodont being Charassognathus from the Wuchiapingian age of the Late Permian. Non-mammalian cynodonts include both carnivorous and herbivorous forms. [REDACTED] Guadalupe Mountains The Guadalupe Mountains ( Spanish : Sierra de Guadalupe ) are

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2604-586: The mountains through the mid-19th century, but they were challenged by an American transportation route at the end of the American Civil War . During the 1840s and 1850s, many people immigrating west crossed the area. In 1858, Pinery station was constructed near Pine Springs for the Butterfield Overland Mail . The Butterfield Overland Mail traveled over Guadalupe Pass located at 5,534 ft (1,687 m) above sea level. A cavalry

2666-519: The other four clades are controversial. The most widely accepted hypothesis of therapsid relationships, the Hopson and Barghausen paradigm, was first proposed in 1986. Under this hypothesis, biarmosuchians are the earliest-diverging major therapsid group, with the other five groups forming the Eutherapsida, and within Eutherapsida, gorgonopsians are the sister taxon of eutheriodonts, together forming

2728-602: The park. Groundwater circulating through deep fractures dissolves limestone and forms extensive cave networks, including the Carlsbad Caverns . Three major ecosystems are contained within the mountain range. First, deserts exhibit salt flats on the western side of the national park and creosote desert , with low elevations on the east covered with grassland , pinyon pine , and junipers such as alligator juniper and one-seeded juniper . Secondly, canyon interiors such as McKittrick, Bear, and Pine Springs Canyon on

2790-461: The pineal foramen, and the foramen is completely absent in probainognathian cynodonts. Evidence from oxygen isotopes, which are correlated with body temperature, suggests that most Permian therapsids were ectotherms and that endothermy evolved convergently in dicynodonts and cynodonts near the end of the Permian. In contrast, evidence from histology suggests that endothermy is shared across Therapsida, whereas estimates of blood flow rate and lifespan in

2852-450: The place in the stratigraphic record where the conodont species Jinogondolella postserrata first appears. The Capitanian Stage was between 265.1 ± 0.4 – 259.8 ± 0.4 Mya. The Guadalupian ended with a deteriorating environment, Greenhouse conditions, and several series of mass-extinctions; both the great dinocephalians , other taxa on land and various invertebrates in the sea. They would be succeeded by new types of therapsids, especially

2914-507: The presence of foramina on the snout of therocephalians and early cynodonts, but the arrangement of foramina in these taxa actually closely resembles lizards, which would make the presence of mammal-like whiskers unlikely. Therapsids evolved from a group of pelycosaurs called sphenacodonts . Therapsids became the dominant land animals in the Middle Permian , displacing the pelycosaurs. Therapsida consists of four major clades :

2976-594: The rocks are now thousands of feet above sea level, sediments that form the rock were deposited in the Delaware Basin , which was a shallow marine coastal setting at the southern edge of what was then the North American craton . Sediments were deposited in an environment that is thought to be similar to present day environments in the Bahamas or southern Florida (U.S.), where warm climate and clear water

3038-581: The scarcely known Kombuisia , and a single group of large stocky herbivores , the Kannemeyeriiformes , which were the only dicynodont lineage to thrive during the Triassic. They and the medium-sized cynodonts (including both carnivorous and herbivorous forms) flourished worldwide throughout the Early and Middle Triassic. They disappear from the fossil record across much of Pangea at the end of

3100-440: The sister taxon of Eutheriodontia, other studies have found dinocephalians and anomodonts to form a clade, and both the phylogenetic position and monophyly of Biarmosuchia remain controversial. In addition to the six major groups, there are several other lineages and species of uncertain classification. Raranimus from the early Middle Permian of China is likely to be the earliest-diverging known therapsid. Tetraceratops from

3162-455: The south, and Sacramento Mountains to the west. One of the clearest exposures of a prehistoric reef is preserved in the mountain range's bedrock geology. Bedrock contains fossils of reef-dwelling organisms from the Permian period , and the geology is widely studied, mostly by stratigraphers , paleontologists , and Paleoecologists (see geology section). Archaeological evidence has shown that people lived over 10,000 years ago in and among

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3224-613: The southeast end exhibit maple , ash , chinquapin oak , and other deciduous trees. These trees are able to grow in the desert due to springs of water recharged by wet uplands. Finally, alpine uplands known as "the Bowl" exceeding elevations of 7,000 ft (2,100 m) are covered with denser forests of ponderosa pine , southwestern white pine , and douglas-fir , with small stands of aspen . The range contains many world-class caves , including Carlsbad Caverns (the best known) and Lechuguilla Cave , discovered in 1986. The history of

3286-605: The southwest tip ends with El Capitan about 90 miles (140 km) east of El Paso. The mountains rise more than 3,000 feet (910 m) above the arid floor of the Chihuahuan Desert . The Guadalupe Mountains are surrounded by the South Plains to the east and north, Delaware Mountains to the south, and Sacramento Mountains to the west. The northwestern extension, bounded by a dramatic escarpment known as "The Rim", extends much further into New Mexico, to near

3348-650: The southwestern United States. Following complete subduction of the Farallon plate in the mid-late Cenozoic, lateral compression was released along the western margin of the North American tectonic plate, and a transform plate boundary formed on the western United States along the San Andreas Fault . Lateral extension of the Colorado Plateau occurred as a result, forming topographic relief and mountainous features along crustal extension features in

3410-421: The sprawling legs of reptiles and pelycosaurs. Also compared to these groups, the feet were more symmetrical, with the first and last toes short and the middle toes long, an indication that the foot's axis was placed parallel to that of the animal, not sprawling out sideways. This orientation would have given a more mammal -like gait than the lizard -like gait of the pelycosaurs. The physiology of therapsids

3472-581: The very hot, dry and oxygen-poor world of the End-Triassic. Dicynodonts were among the most successful groups of therapsids during the Late Permian, and survived through to near the end of the Triassic. Mammals are the only living therapsids. The mammalian crown group , which evolved in the Early Jurassic period, radiated from a group of mammaliaforms that included the docodonts . The mammaliaforms themselves evolved from probainognathians ,

3534-663: Was between 268.8 ± 0.5 – 265.1 ± 0.4 Mya. The base of the Wordian Stage is defined as the place in the stratigraphic record where fossils of conodont species Jinogondolella aserrata first appear. The global reference profile for this stratigraphic boundary is located at Getaway Ledge in the Guadalupe Mountains of Texas . The top of the Wordian (the base of the Capitanian Stage) is defined as

3596-468: Was generated along the margin of the mountain range. The Guadalupe Mountains are mainly carved by a series of NW-SE trending canyons leading to exposure of marine rocks at their current elevation. In the dry, semi-arid environment, continuous limestone bedrock of the Capitan Reef forms large prominent cliffs traceable across the landscape. These cliffs are typically exposed along the eastern edge of

3658-471: Was known as the Buffalo Soldiers was ordered to the area to stop Indian raids on settlements and mail stage routes. During the winter of 1869, Lt. H.B. Cushing led his troops into the Guadalupe Mountains and destroyed two Mescalero Apache camps. The Mescalero Apache were eventually driven out of the area and into US Indian reservations . Felix McKittrick was one of the first European settlers in

3720-622: Was preceded by the Cisuralian and followed by the Lopingian. It is named after the Guadalupe Mountains in New Mexico. The International Chronostratigraphic Chart V2021/07 provides a numerical age of 273.01 ± 0.14 – 259.51 ± 0.21 mya. Therapsids became the dominant land animals in Guadalupian, displacing the pelycosaurs . Therapsids evolved from a group of pelycosaurs called sphenacodonts . Therapsida consists of four major clades :

3782-546: Was prolonged, lasting 30 million years into the Triassic. Several important events took place during Olson's Extinction, most notably the origin of therapsids , a group that includes the evolutionary ancestors of mammals. Further research on the recently identified primitive therapsid of the Xidagou Formation (Dashankou locality) in China of Roadian age may provide more information on this topic. The Wordian Stage

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3844-419: Was thought to be a problem in preservation of fossils. Since the 1990s it has been renamed Olson's Extinction . This extinction event occurred near the beginning of the epoch and led to an extended period of low diversity when two-thirds of terrestrial vertebrate life was lost worldwide. Global diversity rose dramatically by the end probably the result of disaster taxa filling empty guilds, only to fall again when

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