Late Pleistocene

The Late Pleistocene is a geochronological age of the Pleistocene Epoch and is associated with Upper Pleistocene (or Tarantian) stage rocks. The beginning of the stage is defined by the base of the Eemian interglacial phase before the final glacial episode of the Pleistocene 126,000 ± 5,000 years ago. Its end is defined at the end of the Younger Dryas, some 11,700 years ago.[4][5] The age represents the end of the Pleistocene epoch and is followed by the Holocene epoch.

Much of the Late Pleistocene age was dominated by glaciations, such as the Wisconsin glaciation in North America and the Weichselian glaciation and Würm glaciation in Eurasia). Many megafauna became extinct during this age, a trend that continued into the Holocene. The Late Pleistocene contains the Upper Paleolithic stage of human development, including the out-of-Africa migration and dispersal of anatomically modern humans and the extinction of the last remaining archaic human species.

Subdivisions of the Quaternary System
System/
Period
Series/
Epoch
Stage/
Age
Age (Ma)
Quaternary Holocene Meghalayan 0 0.0042
Northgrippian 0.0042 0.0082
Greenlandian 0.0082 0.0117
Pleistocene 'Tarantian' 0.0117 0.126
'Chibanian' 0.126 0.781
Calabrian 0.781 1.80
Gelasian 1.80 2.58
Neogene Pliocene Piacenzian 2.58 3.60
Notes and references[1][2][3]
Subdivision of the Quaternary period according to the ICS, as of 2018.[1]

For the Holocene, dates are relative to the year 2000 (e.g. Greenlandian began 11,700 years before 2000). For the begin of the Northgrippian a date of 8,236 years before 2000 has been set.[2] The Meghalayan has been set to begin 4,250 years before 2000, apparently from a calibrated radio-carbon date of 4,200 years BP i.e. before 1950.[3]

'Chibanian' and 'Tarantian' are informal, unofficial names proposed to replace the also informal, unofficial 'Middle Pleistocene' and 'Upper Pleistocene' subseries/subepochs respectively.

In Europe and North America, the Holocene is subdivided into Preboreal, Boreal, Atlantic, Subboreal, and Subatlantic stages of the Blytt–Sernander time scale. There are many regional subdivisions for the Upper or Late Pleistocene; usually these represent locally recognized cold (glacial) and warm (interglacial) periods. The last glacial period ends with the cold Younger Dryas substage.

North America

According to George Carr Frison, Bison occidentalis and Bison antiquus, an extinct subspecies of the smaller present-day bison, survived the Late Pleistocene period, between about 12 and 11 ka ago. Plains and Rocky Mountain First Nations depended on these bison as their major food source.[6][Notes 1] Earlier kills of camels, horses, and muskoxen found at Wally's beach were dated to 13.1–13.3 ka B.P.[7]

Göbekli Tepe

Göbekli Tepe is the only known major Pleistocene architectural constriction. It was used into the earliest Holocene epoch.

Notes

  1. ^ Frison noted that the "oldest, well-documented bison kills by pedestrian human hunters in North America date to about 11,000 years ago".

Citations

  1. ^ a b Cohen, K.M.; Finney, S.C.; Gibbard, P.L.; Fan, J.-X. "International Chronostratigraphic Chart". International Commission on Stratigraphy. Retrieved July 10, 2018.
  2. ^ a b "IUGS ratifies Holocene". Retrieved 18 August 2018.
  3. ^ a b "announcement ICS chart v2018/07". Retrieved 9 August 2018.
  4. ^ Walker et al. 2009, p. 3.
  5. ^ "Major Divisions". Subcommission on Quaternary Stratigraphy. International Commission on Stratigraphy. 4 January 2016. Retrieved 25 January 2017.. For the top of the series, see: Lourens, L., Hilgen, F., Shackleton, N.J., Laskar, J., Wilson, D., (2004) "The Neogene Period". In: Gradstein, F., Ogg, J., Smith, A.G. (Eds.), A Geologic Time Scale 2004. Cambridge: Cambridge University Press.
  6. ^ Frison 2000.
  7. ^ Michael R. Waters; Thomas W. Stafford Jr.; Brian Kooyman; L. V. Hills (March 23, 2015). "Late Pleistocene horse and camel hunting at the southern margin of the ice-free corridor: Reassessing the age of Wally's Beach, Canada". PNAS. doi:10.1073/pnas.1420650112. PMC 4394292.

References

Further reading

  • Ehlers, J., and P.L. Gibbard, 2004a, Quaternary Glaciations: Extent and Chronology 2: Part II North America. Elsevier, Amsterdam. ISBN 0-444-51462-7
  • Ehlers, J., and P L. Gibbard, 2004b, Quaternary Glaciations: Extent and Chronology 3: Part III: South America, Asia, Africa, Australia, Antarctica. ISBN 0-444-51593-3
  • Gillespie, A.R., S.C. Porter, and B.F. Atwater, 2004, The Quaternary Period in the United States. Developments in Quaternary Science no. 1. Elsevier, Amsterdam. ISBN 978-0-444-51471-4
  • Mangerud, J., J. Ehlers, and P. Gibbard, 2004, Quaternary Glaciations : Extent and Chronology 1: Part I Europe. Elsevier, Amsterdam. ISBN 0-444-51462-7
  • Sibrava, V., Bowen, D.Q, and Richmond, G.M., 1986, Quaternary Glaciations in the Northern Hemisphere, Quaternary Science Reviews. vol. 5, pp. 1–514.

Paleoclimatology stages

Arlington Springs Man

The Arlington Springs man is a set of Late Pleistocene human remains discovered on Santa Rosa Island, one of the Channel Islands located off the coast of Southern California. The Arlington Springs archeological site is protected within northern Channel Islands National Park, and in Santa Barbara County.

Dire wolf

The dire wolf (Canis dirus, "fearsome dog") is an extinct species of the genus Canis. It is one of the most famous prehistoric carnivores in North America, along with its extinct competitor, the sabre-toothed cat Smilodon fatalis. The dire wolf lived in the Americas during the Late Pleistocene and Early Holocene epochs (125,000–9,440 years ago). The species was named in 1858, four years after the first specimen had been found. Two subspecies are recognized: Canis dirus guildayi and Canis dirus dirus. The dire wolf probably evolved from Armbruster's wolf (Canis armbrusteri) in North America. The largest collection of its fossils has been obtained from the Rancho La Brea Tar Pits in Los Angeles.

Dire wolf remains have been found across a broad range of habitats including the plains, grasslands, and some forested mountain areas of North America, and in the arid savannah of South America. The sites range in elevation from sea level to 2,255 meters (7,400 ft). Dire wolf fossils have rarely been found north of 42°N latitude; there have been only five unconfirmed reports above this latitude. This range restriction is thought to be due to temperature, prey, or habitat limitations imposed by proximity to the Laurentide and Cordilleran ice sheets that existed at the time.

The dire wolf was about the same size as the largest modern gray wolves (Canis lupus): the Yukon wolf and the northwestern wolf. C. d. guildayi weighed on average 60 kilograms (132 lb) and C. d. dirus was on average 68 kg (150 lb). Its skull and dentition matched those of C. lupus, but its teeth were larger with greater shearing ability, and its bite force at the canine tooth was the strongest of any known Canis species. These characteristics are thought to be adaptations for preying on Late Pleistocene megaherbivores, and in North America its prey are known to have included horses, ground sloths, mastodons, bison, and camels. As with other large Canis hypercarnivores today, the dire wolf is thought to have been a pack hunter. Its extinction occurred during the Quaternary extinction event along with most of the American megafauna of the time, including a number of other carnivores, that occurred soon after the appearance of humans in the New World. Its reliance on megaherbivores has been proposed as the cause of its extinction, along with climate change and competition with other species, but the cause remains controversial. Dire wolves lived as recently as 9,440 years ago, according to dated remains.

European ass

The European ass (Equus hydruntinus) is an extinct equine from the middle and late Pleistocene of Eurasia. It appeared first in the fossil report 300,000 years before present and did not disappear until Holocene times. In the late Pleistocene it was widespread throughout much of western Eurasia from the Middle East to Europe, especially along the Mediterranean, with fossil reports from Sicily, Turkey, Spain, France and Portugal. In the east the range apparently stretched at least to the Volga and to Iran. In the north it reached almost to the North Sea in Germany. It is possible that the Iberian "cebro", extinct in the wild from the 16th century, could correspond to the Equus hydruntinus, although the word "cebro" comes from Latin equiferus meaning 'wild horse'. Morphologically the European ass can be distinguished from asses and hemiones particularly by its molars and the relatively short nares. The exact systematic position is still not fully clear, but genetic and morphological analysis suggest that it is closely related to the Asiatic wild ass.

Glacial Lake Nantucket Sound

Glacial Lake Nantucket Sound was a glacial lake that formed during the late Pleistocene epoch inside modern Nantucket Sound. After the Laurentide ice sheet retreated, glacial ice melt washed over the terminal moraine of Cape Cod and the glacial meltwater settled in the modern day sound, creating the lake.

Hesperotestudo

Hesperotestudo ("Western turtle") is an extinct genus of tortoise that lived from the Miocene to the Pleistocene. Its remains are known from North America, Central America and Bermuda. Further specimens identifiable only to genus have been found in El Salvador (TEWG, 2015).

Megalomys curazensis

Megalomys curazensis is a species of rodent from the Late Pleistocene (400,000 to 130,000 years ago) of the island of Curaçao, off northwestern Venezuela. It is a member of the genus Megalomys, which also includes species from other islands of the Lesser Antilles. It is known from abundant but fragmentary material found throughout the island.

Nevado del Tolima

The Nevado del Tolima is a Late Pleistocene to recently active andesitic stratovolcano located in the Tolima department, Colombia. The volcano lies south of Nevado del Ruiz volcano and is situated within the Los Nevados National Natural Park. The volcano, whose most recent activity dates to 1943 and last major eruption around 3600 years ago, overlies the Eocene El Bosque Batholith, dated at 49.1 ± 1.7 Ma.

Panthera pardus spelaea

Panthera pardus spelaea, sometimes called the European Ice Age leopard or Late Pleistocene Ice Age leopard, is a fossil leopard subspecies, which roamed Europe in the Late Pleistocene. The youngest known bone fragments date to about 32,000 to 26,000 years ago, and are similar in size to modern leopard bones.

Panthera spelaea

Panthera spelaea, also known as the Eurasian cave lion, European cave lion, or steppe lion, is an extinct Panthera species that evolved in Europe probably after the third Cromerian interglacial stage, less than 600,000 years ago. Phylogenetic analysis of fossil bone samples revealed that it was highly distinct and genetically isolated from the modern lion (Panthera leo) occurring in Africa and Asia. Analysis of morphological differences and mitochondrial data support the taxonomic recognition of Panthera spelaea as a distinct species that diverged from the lion about 1.9 million years ago.

The oldest known bone fragments were excavated in Yakutia and radiocarbon dated at least 62,400 years old. It became extinct about 13,000 years ago.

Pleistocene coyote

The Pleistocene coyote (Canis latrans orcutti), also known as the Ice Age coyote, is an extinct subspecies of coyote that lived in western North America during the Late Pleistocene era. Most remains of the subspecies were found in southern California, though at least one was discovered in Idaho. It was part of a carnivore guild that included other canids like foxes, gray wolves, and dire wolves.Compared to their modern Holocene counterparts, Pleistocene coyotes were larger and more robust, weighing 39–46 lb (18–21 kg), likely in response to larger competitors and prey rather than Bergmann's rule. Their skulls and jaws were significantly thicker and deeper than in modern coyotes, with a shorter and broader rostrum and wider carnassial (denoting the large upper premolar and lower molar teeth of a carnivore, adapted for shearing flesh) teeth. These adaptions allowed it to cope with higher levels of stress, when it killed larger prey, compared to modern coyotes. Pleistocene coyotes were also likely more specialized carnivores than their descendants, as their teeth were more adapted to shearing meat, showing fewer grinding surfaces which were better suited for processing vegetation. The lower jaw was also deeper, and the molars showed more signs of wear and breakage than modern populations, thus indicating that the animals consumed more bone than today. Behaviorally, it is likely to have been more social than the modern coyote, as its remains are the third most common in the La Brea Tar Pits, after dire wolves and sabre-toothed cats, both thought to be gregarious species.Their reduction in size occurred within 1,000 years of the occurrence of the Quaternary extinction event, when the climate changed and the majority of their larger prey became extinct. Furthermore, Pleistocene coyotes were unable to successfully exploit the big game hunting niche left vacant after the extinction of the dire wolf, as that gap was rapidly filled by gray wolves. These gray wolves are likely to have actively killed off the larger-bodied coyotes, with natural selection favoring the modern gracile morph. Human predation on the Pleistocene coyote's dwindling prey base may have also impacted the animal's change in morphology.

Podilymbus

Podilymbus is a genus of birds in the Podicipedidae family, containing the extinct Atitlán grebe (Podilymbus gigas) and the pied-billed grebe (Podilymbus podiceps). The genus name is derived from Latin Podilymbus, a contraction of podicipes ("feet at the buttocks", from podici-, "rump-" + pes, "foot")—the origin of the name of the grebe order—and Ancient Greek kolymbos, "diver".There are also several prehistoric taxa of Podilymbus described from fossil remains:

Podilymbus majusculus (Late Pliocene of Wisconsin)

Podilymbus wetmorei (Late Pleistocene of Florida)

Podilymbus podiceps magnus - a paleosubspecies of the pied-billed grebe of uncertain validity.

Proglacial lake

In geology, a proglacial lake is a lake formed either by the damming action of a moraine during the retreat of a melting glacier, a glacial ice dam, or by meltwater trapped against an ice sheet due to isostatic depression of the crust around the ice. At the end of the last ice age about 10,000 years ago, large proglacial lakes were a widespread feature in the northern hemisphere.

Puffin

Puffins are any of three small species of alcids (auks) in the bird genus Fratercula with a brightly coloured beak during the breeding season. These are pelagic seabirds that feed primarily by diving in the water. They breed in large colonies on coastal cliffs or offshore islands, nesting in crevices among rocks or in burrows in the soil. Two species, the tufted puffin and horned puffin, are found in the North Pacific Ocean, while the Atlantic puffin is found in the North Atlantic Ocean.

All puffin species have predominantly black or black and white plumage, a stocky build, and large beaks. They shed the colourful outer parts of their bills after the breeding season, leaving a smaller and duller beak. Their short wings are adapted for swimming with a flying technique under water. In the air, they beat their wings rapidly (up to 400 times per minute) in swift flight, often flying low over the ocean's surface.

A significant decline in numbers of puffins on Shetland is worrying scientists.

Quaternary extinction event

The Quaternary period (from 2.588 ± 0.005 million years ago to the present) saw the extinctions of numerous predominantly megafaunal species, which resulted in a collapse in faunal density and diversity and the extinction of key ecological strata across the globe. The most prominent event in the Late Pleistocene is differentiated from previous Quaternary pulse extinctions by the widespread absence of ecological succession to replace these extinct species, and the regime shift of previously established faunal relationships and habitats as a consequence.

The earliest casualties were incurred at 130,000 BCE (the start of the Late Pleistocene). However, the great majority of extinctions in Afro-Eurasia and the Americas occurred during the transition from the Pleistocene to the Holocene epoch (13,000 BCE to 8,000 BCE). This extinction wave did not stop at the end of the Pleistocene, continuing, especially on isolated islands, in human-caused extinctions, although there is debate as to whether these should be considered separate events or part of the same event.Among the main causes hypothesized by paleontologists are overkill by the widespread appearance of humans and natural climate change. A notable modern human presence first appeared during the Middle Pleistocene in Africa, and started to establish continuous, permanent populations in Eurasia and Australasia from 120,000 BCE and 63,000 BCE respectively, and the Americas from 22,000 BCE.A variant of the former possibility is the second-order predation hypothesis, which focuses more on the indirect damage caused by overcompetition with nonhuman predators. Recent studies have tended to favor the human-overkill theory.

Rancholabrean

The Rancholabrean North American Land Mammal Age on the geologic timescale is the North American faunal stage according to the North American Land Mammal Ages chronology (NALMA), typically set from less than 240,000 years to 11,000 years BP, a period of 0.229 million years. Named after the famed Rancho La Brea fossil site (more commonly known as the La Brea tar pits) in Los Angeles, California, the Rancholabrean is characterized by the presence of the genus Bison in a Pleistocene context, often in association with other extinct Pleistocene forms such as Mammuthus. The age is usually considered to overlap the Middle Pleistocene and Late Pleistocene epochs. The Rancholabrean is preceded by the Irvingtonian NALMA stage.

The Rancholabrean can be further divided into the substages of:

Sheridanian: Upper boundary source of the base of the Holocene (approximate)The Rancholabrean shares this time period with the Oldenburgian of European Land Mammal Ages.

Stegodon

Stegodon, meaning "roofed tooth" (from the Ancient Greek words στέγω, stégō, 'to cover', + ὀδούς, odoús, 'tooth') because of the distinctive ridges on the animal's molars, is a genus of the extinct subfamily Stegodontinae of the order Proboscidea. It was assigned to the family Elephantidae (Abel, 1919), but has also been placed in the Stegodontidae (R. L. Carroll, 1988). Stegodonts were present from 11.6 million years ago (Mya) to the late Pleistocene, with unconfirmed records of localized survival until 4,100 years ago. Fossils are found in Asian and African strata dating from the late Miocene; during the Pleistocene, they lived across large parts of Asia and East and Central Africa.A review of 130 papers written about 180 different sites with proboscidean remains in southern China revealed Stegodon to have been more common than Asian elephants; the papers gave many recent radiocarbon dates, the youngest being 2,150 BCE (4,100 BP). However, Turvey et al. (2013) reported that one of the faunal assemblages including supposed fossils of Holocene Stegodon (from Gulin, Sichuan Province) is actually late Pleistocene in age; other supposed fossils of Holocene stegodonts were lost and their age cannot be verified. The authors concluded that the latest confirmed occurrences of Stegodon from China are from the late Pleistocene, and that its Holocene survival cannot be substantiated.

Tham Lod rockshelter

Tham Lod Rockshelter (Thai: เพิงผาถ้ำลอด), first researched by Rasmi Shoocongdej from Silpakorn University, funded by the Thai Research Fund, was a prehistoric cemetery and a workshop located in Northern Thailand known to have human inhabitants from the late Pleistocene to the late Holocene period Additionally, Tham Lod is near Ban Rai, another rock shelter and is in the vicinity of two well known caves, Spirit Cave and Tham Lot cave. Recent researches and carbon dating suggested that Homo sapiens have occupied the area. These researches provide more detail on the activities by the humans in the area which includes burials, living habits, gathering, and tool making, and social interactions.

West Napa Fault

The West Napa Fault is a 57 km (35 mi) long geologic fault in Napa County, in the North Bay region of the San Francisco Bay Area in northern California. It is believed to be the northern extension of the Calaveras Fault in the East Bay region.

It has been mapped as a Late Pleistocene-Holocene active fault, and is considered to be predominantly a right lateral strike-slip fault. The fault was discovered in 1976 by Gene Boudreau, a ground water drilling specialist from Sebastopol.

Zhiren Cave

Zhiren Cave (Chinese: 智人洞) is a karstic cave in the Mulan Mountains that overlooks the Hejiang River in Chongzuo, Guangxi, China. Zhiren Cave is an early Late Pleistocene site that has yielded the fossil remains of possibly anatomically modern humans with some mixed archaic human features.

Cenozoic era
(present–66.0 Mya)
Mesozoic era
(66.0–251.902 Mya)
Paleozoic era
(251.902–541.0 Mya)
Proterozoic eon
(541.0 Mya–2.5 Gya)
Archean eon (2.5–4 Gya)
Hadean eon (4–4.6 Gya)

This page is based on a Wikipedia article written by authors (here).
Text is available under the CC BY-SA 3.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.