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159-432: A mastodon ( mastós 'breast' + odoús 'tooth') is a member of the genus Mammut (German for 'mammoth'), which was endemic to North America and lived from the late Miocene to the early Holocene . Mastodons belong to the order Proboscidea , the same order as elephants and mammoths (which belong to the family Elephantidae ). Mammut is the type genus of the extinct family Mammutidae , which diverged from

318-473: A monotreme , appeared. The predatory South American phorusrhacids were rare in this time; among the last was Titanis , a large phorusrhacid that migrated to North America and rivaled mammals as top predator. Other birds probably evolved at this time, some modern (such as the genera Cygnus , Bubo , Struthio and Corvus ), some now extinct. Alligators and crocodiles died out in Europe as

477-542: A broader aridification trend. The EMCI ended 18 million years ago, giving way to the Middle Miocene Warm Interval (MMWI), the warmest part of which was the MMCO that began 16 million years ago. As the world transitioned into the MMCO, carbon dioxide concentrations varied between 300 and 500 ppm. Global annual mean surface temperature during the MMCO was about 18.4 °C. MMCO warmth was driven by

636-529: A clade of large terrestrial predatory crocodyliformes distantly related to modern crocodilians, from which they likely diverged over 180 million years ago, are known from the Miocene of South America. The last Desmostylians thrived during this period before becoming the only extinct marine mammal order. The pinnipeds , which appeared near the end of the Oligocene, became more aquatic. A prominent genus

795-570: A cooler, drier climate. C 4 grasses, which are able to assimilate carbon dioxide and water more efficiently than C 3 grasses, expanded to become ecologically significant near the end of the Miocene between 6 and 7 million years ago, although they did not expand northward during the Late Miocene. The expansion of grasslands and radiations among terrestrial herbivores correlates to fluctuations in CO 2 . One study, however, has attributed

954-712: A family of the Elephantimorpha clade, it is only distantly related to the Deinotheriidae due to major differences in dentition and emergence of adult teeth. The Mammutidae is identified as a monophyletic clade, meaning that it did not leave any derived descendant groups in its evolutionary history. The monophyly of the Mammutidae makes it differ from the Elephantida, where the Gomphotheriidae

1113-486: A good analogue for future warmer climates caused by anthropogenic global warming , with this being especially true of the global climate during the Middle Miocene Climatic Optimum (MMCO), because the last time carbon dioxide levels were comparable to projected future atmospheric carbon dioxide levels resulting from anthropogenic climate change was during the MMCO. The Ross Sea margin of

1272-435: A good model for a "living fossil". Eucalyptus fossil leaves occur in the Miocene of New Zealand , where the genus is not native today, but have been introduced from Australia . Both marine and continental fauna were fairly modern, although marine mammals were less numerous. Only in isolated South America and Australia did widely divergent fauna exist. In Eurasia, genus richness shifted southward to lower latitudes from

1431-632: A greater understanding of extinctions. Taxonomically, it was first recognized as a distinct species by Robert Kerr in 1792 then classified to its own genus Mammut by Johann Friedrich Blumenbach in 1799, thus making it amongst the first fossil mammal genera to be erected with undisputed taxonomic authority. The genus served as a wastebasket taxon for proboscidean species with superficially similar molar teeth morphologies but today includes 7 definite species, 1 of questionable affinities, and 4 other species from Eurasia that are pending reassessments to other genera. Mastodons are considered to have had

1590-406: A large neocortex relative to body mass and stone tool manufacture. Improvements in dating methods and in the use of climate proxies have provided scientists with the means to test hypotheses of the evolution of human ancestors. Early hypotheses of the evolution of human traits emphasized the selective pressures produced by particular habitats. For example, many scientists have long favored

1749-578: A letter dating to 1713, Edward Hyde, 3rd Earl of Clarendon (known also as Lord Cornbury) from New York reported to the Royal Society learned society of Great Britain that in 1705, a large-sized tooth was found near the side of the Hudson River by a Dutch country-fellow and was sold to New York General Assembly member Van Bruggen for a gill of rum, and Bruggen eventually gave it to Cornbury. He then stated that he sent Johannis Abeel,

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1908-658: A long and complex paleontological history spanning all the way back to 1705 when the first fossils were uncovered from Claverack , New York in the American colonies. Because of the uniquely shaped molars with no modern analogues in terms of large animals, the species caught wide attention of European researchers and influential Americans before and after the American Revolution to the point of, according to American historians Paul Semonin and Keith Stewart Thomson , bolstering American nationalism and contributing to

2067-598: A major expansion of Antarctic glaciers. This severed the connection between the Indian Ocean and the Mediterranean Sea and formed the present land connection between Afro-Arabia and Eurasia. The subsequent uplift of mountains in the western Mediterranean region and a global fall in sea levels combined to cause a temporary drying up of the Mediterranean Sea (known as the Messinian salinity crisis ) near

2226-480: A major expansion of grass-grazer ecosystems . Herds of large, swift grazers were hunted by predators across broad sweeps of open grasslands , displacing desert, woodland, and browsers . The higher organic content and water retention of the deeper and richer grassland soils , with long-term burial of carbon in sediments, produced a carbon and water vapor sink. This, combined with higher surface albedo and lower evapotranspiration of grassland, contributed to

2385-479: A majority known from endocasts , including M. americanum : Phosphatherium esculliei [REDACTED] Numidotherium koholense [REDACTED] Moeritherium lyonsi [REDACTED] Deinotheriidae [REDACTED] Palaeomastodon beadnelli [REDACTED] Miocene As Earth went from the Oligocene through the Miocene and into the Pliocene, the climate slowly cooled towards

2544-429: A particular habitat. The change to a cooler, drier, more seasonal climate had considerable impacts on Pliocene vegetation, reducing tropical species worldwide. Deciduous forests proliferated, coniferous forests and tundra covered much of the north, and grasslands spread on all continents (except Antarctica). Eastern Africa in particular saw a huge expansion of C 4 grasslands. Tropical forests were limited to

2703-655: A predominantly browsing -based diet on leaves, fruits, and woody parts of plants. This allowed mastodons to niche partition with other members of Proboscidea in North America, like gomphotheres and the Columbian mammoth , who had shifted to mixed feeding or grazing by the late Neogene - Quaternary . It is thought that mastodon behaviors were not much different from elephants and mammoths, with females and juveniles living in herds and adult males living largely solitary lives plus entering phases of aggression similar to

2862-640: A recorder of Albany , New York to dig near the original site of the tooth to find more bones. Abeel reported in a later that he went to the town of Claverack , New York where the original bones were found. American historian Paul Semonin said that the accounts written by Cornbury and Abeel match up with that written by in the July 30, 1705 entry in The Boston News-Letter . The account reported skeletal evidence of an antediluvian (or biblical) " giant " uncovered from Claverack. The femur and one of

3021-540: A second species for Pliomastodon named P. vexillarius based on fossil material from the locality of Elephant Hill in California , determining that it differs from Mammut by differences in the skull and that the etymology of the species name was made in honor of paleontological contributions by the Standard Oil Company of California. In 1933, Childs Frick named the species Mastodon raki from

3180-588: A series of ice ages . The Miocene boundaries are not marked by distinct global events but by regionally defined transitions from the warmer Oligocene to the cooler Pliocene Epoch. During the Early Miocene, Afro-Arabia collided with Eurasia, severing the connection between the Mediterranean and Indian Oceans, and allowing the interchange of fauna between Eurasia and Africa, including the dispersal of proboscideans and hominoids into Eurasia. During

3339-539: A significant drop in atmospheric carbon dioxide levels. Both continental and oceanic thermal gradients in mid-latitudes during the Early Miocene were very similar to those in the present. Global cooling caused the East Asian Summer Monsoon (EASM) to begin to take on its modern form during the Early Miocene. From 22.1 to 19.7 Ma, the Xining Basin experienced relative warmth and humidity amidst

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3498-700: A significant local decline along the northeastern coast of Australia during the Tortonian, most likely due to warming seawater. Cetaceans attained their greatest diversity during the Miocene, with over 20 recognized genera of baleen whales in comparison to only six living genera. This diversification correlates with emergence of gigantic macro-predators such as megatoothed sharks and raptorial sperm whales . Prominent examples are O. megalodon and L. melvillei . Other notable large sharks were O. chubutensis , Isurus hastalis , and Hemipristis serra . Crocodilians also showed signs of diversification during

3657-615: A spring on the Pomme de Terre River to assemble a mounted skeleton of the " Missouri Leviathan " and briefly exhibited it at St. Louis . After exhibiting the skeleton throughout Europe, he sold the skeleton to the British Museum of Natural History . Richard Owen then properly reassembled the skeleton, and it today is on display there. In 1845, another skeleton was excavated from Newburgh by laborers hired by Nathaniel Brewster initially to remove lacustrine deposits to fertilize

3816-968: A tight band around the equator, and in addition to dry savannahs , deserts appeared in Asia and Africa. Both marine and continental faunas were essentially modern, although continental faunas were a bit more primitive than today. The land mass collisions meant great migration and mixing of previously isolated species, such as in the Great American Interchange . Herbivores got bigger, as did specialized predators. In North America, rodents , large mastodons and gomphotheres , and opossums continued successfully, while hoofed animals ( ungulates ) declined, with camel , deer , and horse all seeing populations recede. Three-toed horses ( Nannippus ), oreodonts , protoceratids , and chalicotheres became extinct. Borophagine dogs and Agriotherium became extinct, but other carnivores including

3975-426: A view followed also by George William Featherstonhaugh . Isaac Hays comparatively defended Godman's taxon, which led to a bitter debate regarding the validity of the genus amongst American naturalists. The validities of both Tetracaulodon and Missourium were rejected by Owen in 1842, although he retained the former name informally. By 1869, American paleontologist Joseph Leidy determined that Mastodon americanus

4134-407: A view later followed by Franklin. In 1768, Scottish anatomist William Hunter recorded that he and his brother John Hunter observed that the teeth were not like those of modern elephants. He determined that the "grinders" from Ohio were of a carnivorous animal but believed that the tusks belonged to the same animal. After examining fossils from Franklin and Lord Shelburne, Hunter was convinced that

4293-651: A zone of low rainfall in the Late Miocene. The Indian Plate continued to collide with the Eurasian Plate , creating new mountain ranges and uplifting the Tibetan Plateau , resulting in the rain shadowing and aridification of the Asian interior. The Tian Shan experienced significant uplift in the Late Miocene, blocking westerlies from coming into the Tarim Basin and drying it as a result. At

4452-670: Is Z. proavus , which occurs in the Barstovian and Clarendonian stages. M? furlongi from the Black Butte in Oregon also dates back to the Clarendonian stage, but the affinities of the species remains unclear. If it truly is a species of Mammut , then its earliest temporal range is recorded at about 10 Ma. The earliest undisputed appearance of Mammut is of M. nevadanum from Thousand Creek Beds, dating back to

4611-474: Is paraphyletic (or ancestral to more derived descendant groups in the cladistic sense) in relation to the derived elephantoid families Stegodontidae and Elephantidae (elephants, mammoths, and relatives). Although the separation of the Mammutida and Elephantida is strongly supported based on morphological differences, their origins within the late Paleogene remain uncertain. One hypothesis asserts that

4770-496: Is a key finding of research into a lake-sediment core obtained in Eastern Siberia, which is of exceptional importance because it has provided the longest continuous late Cenozoic land-based sedimentary record thus far. During the late Zanclean, Italy remained relatively warm and humid. Central Asia became more seasonal during the Pliocene, with colder, drier winters and wetter summers, which contributed to an increase in

4929-608: Is extinct and has left no living descendants. He established that it had an overall body form similar to elephants but had molars more similar to hippopotamuses and pigs that did not serve to grind meat. The first species he erected within Mastodon was Mastodon giganteum , giving it the informal name "great mastodon" and writing that that it is designated to the Ohio proboscidean with abundant fossil evidence, equal size but greater proportions to modern elephants, and diamond-shaped points of

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5088-722: Is the epoch in the geologic time scale that extends from 5.33 to 2.58 million years ago (Ma). It is the second and most recent epoch of the Neogene Period in the Cenozoic Era . The Pliocene follows the Miocene Epoch and is followed by the Pleistocene Epoch. Prior to the 2009 revision of the geologic time scale, which placed the four most recent major glaciations entirely within the Pleistocene,

5247-478: Is the type genus of the Mammutidae , the sole family of the elephantimorph clade Mammutida (the other elephantimorph clade is Elephantida ). The Mammutidae is characterized by molars with zygodont-form crests, which have remained morphologically conservative throughout the evolutionary history of the family. Mammut is considered to be a derived genus of the family because of strong zygodont development. As

5406-401: Is the senior species synonym and listed M. giganteum as a junior synonym. He also listed Mammut , Harpagmotherium , Mastotherium , Missourium , and Leviathan as synonyms of Mastodon . He also noted that M. americanum as a species was highly variable in morphology. In 1902, American paleontologist Oliver Perry Hay listed Mammut as the prioritized genus name given its status as

5565-727: The American Museum of Natural History . Other skeletons of Mammut americanum were excavated within the United States in the first half of the 19th century. One of them was collected by American showman Albert C. Koch in what is today the Mastodon State Historic Site at Missouri in 1839. He hypothesized in 1840 that the proboscidean, which he classified as Missourium , was much larger than an elephant, had horizontal tusks plus trunks, and occupied aquatic habitats. He acquired additional fossils from

5724-575: The Clovis culture ) hunted mastodons based on the finding of mastodon remains with cut marks and/or with lithic artifacts. Mastodons disappeared along with many other North American animals, including most of its largest animals ( megafauna ), as part of the end-Pleistocene extinction event around the end of the Late Pleistocene-early Holocene, the causes typically being attributed to human hunting, severe climatic phases like

5883-688: The Coso Mountains in Inyo County , California where skull fossils were recovered. In 1963, J. Arnold Shotwell and Donald E. Russell created another species Mammut (Pliomastodon) furlongi , assigning it to fossils collected from the Juntura Formation of Oregon. The species name was created in honor of Eustace L. Furlong , who made early fossil collections from the western side of the Juntura Basin. The genus Pliomastodon

6042-588: The Hardangervidda plateau to 1200 m in the Early Pliocene. In Southern Sweden similar movements elevated the South Swedish highlands leading to a deflection of the ancient Eridanos river from its original path across south-central Sweden into a course south of Sweden. The Pliocene is bookended by two significant events in the evolution of human ancestors. The first is the appearance of

6201-549: The Irvingtonian to the Rancholabrean (from around 1.6 million to 11,000 years ago), only M. americanum and the newly appearing M. pacificum are recorded, the former having an exceptional level of diversity based on abundant skeletal evidences from the late Pleistocene that is unusual for the typical mammutid fossil record. The following cladogram defines the phylogeny of certain proboscideans,

6360-686: The Isthmus of Panama during the Pliocene, making possible the Great American Interchange and bringing a nearly complete end to South America's distinctive native ungulate fauna, though other South American lineages like its predatory mammals were already extinct by this point and others like xenarthrans continued to do well afterwards. The formation of the Isthmus had major consequences on global temperatures, since warm equatorial ocean currents were cut off and an Atlantic cooling cycle began, with cold Arctic and Antarctic waters decreasing temperatures in

6519-559: The Middle Miocene Climate Transition (MMCT). Abrupt increases in opal deposition indicate this cooling was driven by enhanced drawdown of carbon dioxide via silicate weathering. The MMCT caused a sea surface temperature (SST) drop of approximately 6 °C in the North Atlantic. The drop in benthic foraminiferal δ O values was most noticeable in the waters around Antarctica, suggesting cooling

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6678-571: The Netherlands the Pliocene is divided into these stages (old to young): Brunssumian C, Reuverian A, Reuverian B, Reuverian C, Praetiglian , Tiglian A, Tiglian B, Tiglian C1-4b, Tiglian C4c, Tiglian C5, Tiglian C6 and Eburonian . The exact correlations between these local stages and the International Commission on Stratigraphy (ICS) stages is not established. During the Pliocene epoch (5.3 to 2.6 million years ago (Ma)),

6837-478: The North Atlantic and North Pacific Ocean beds. Mid-latitude glaciation was probably underway before the end of the epoch. The global cooling that occurred during the Pliocene may have accelerated on the disappearance of forests and the spread of grasslands and savannas. During the Pliocene the earth climate system response shifted from a period of high frequency-low amplitude oscillation dominated by

6996-660: The Snake Creek Formation of western Nebraska , naming it in honor of William Diller Matthew . He also erected another species M. merriami from the Thousand Creek Formation in Nevada , which was eventually synonymized with Zygolophodon proavus . Osborn in 1926 followed up for Mastodon matthewi by establishing the genus Pliomastodon for the species based on cranial differences from " Miomastodon " (= Zygolophodon ). In 1930, Matthew erected

7155-482: The Younger Dryas , or some combination of the two. The American mastodon had its last recorded occurrence in the earliest Holocene around 11,000 years ago, which is considerably later than other North American megafauna species. Today, the American mastodon is one of the most well-known fossil species in both academic research and public perception, the result of its inclusion in American popular culture. In

7314-560: The carbon cycle occurred approximately 6 Ma, causing continental carbon reservoirs to no longer expand during cold spells, as they had done during cold periods in the Oligocene and most of the Miocene. At the end of the Miocene, global temperatures rose again as the amplitude of Earth's obliquity increased, which caused increased aridity in Central Asia. Around 5.5 Ma, the EAWM underwent a period of rapid intensification. Life during

7473-497: The hominin Australopithecus anamensis in the early Pliocene, around 4.2 million years ago. The second is the appearance of Homo , the genus that includes modern humans and their closest extinct relatives, near the end of the Pliocene at 2.6 million years ago. Key traits that evolved among hominins during the Pliocene include terrestrial bipedality and, by the end of the Pliocene, encephalized brains (brains with

7632-533: The musth exhibited by modern elephants. Mammut achieved maximum species diversity in the Pliocene , though the genus is known from abundant fossil evidence in the Late Pleistocene . Mastodons for at least a few thousand years prior to their extinction coexisted with Paleoindians , who were the first humans to have inhabited North America. Evidence has been found that Paleoindians (including those of

7791-634: The savannah hypothesis . This proposes that the evolution of terrestrial bipedality and other traits was an adaptive response to Pliocene climate change that transformed forests into more open savannah . This was championed by Grafton Elliot Smith in his 1924 book, The Evolution of Man , as "the unknown world beyond the trees", and was further elaborated by Raymond Dart as the killer ape theory . Other scientists, such as Sherwood L. Washburn , emphasized an intrinsic model of hominin evolution. According to this model, early evolutionary developments triggered later developments. The model placed little emphasis on

7950-493: The weasel family diversified, and dogs and short-faced bears did well. Ground sloths , huge glyptodonts , and armadillos came north with the formation of the Isthmus of Panama. The latitudinal diversity gradient among terrestrial North American mammals became established during this epoch some time after 4 Ma. In Eurasia rodents did well, while primate distribution declined. Elephants , gomphotheres and stegodonts were successful in Asia (the largest land mammals of

8109-550: The " pseudo-elephant ", or " animal incognitum " (shortened as " incognitum "), was an animal species separate from elephants that might have also been the same as the proboscideans found in Siberia. He concluded his article with the opinion that although regrettable to philosophers, humanity should be thankful to heaven that the animal, if truly carnivorous, was extinct. In 1785, Reverend Robert Annan wrote an account recalling an event in which workers discovered bones in his farm near

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8268-540: The 19th century before eventually being reclassified into distinct genera. In addition to still-valid species names, several synonymous or dubious species names ultimately belonging to different genera were erected within the Americas as well throughout the 19th century. Also, many species names erected based on M. americanum remains were erected. As a result, M. americanum has many synonymous names. The issue of synonymous species names were especially apparent in

8427-469: The 41,000-year period of Earth's obliquity to one of low-frequency, high-amplitude oscillation dominated by the 100,000-year period of the orbital eccentricity characteristic of the Pleistocene glacial-interglacial cycles. During the late Pliocene and early Pleistocene, 3.6 to 2.6 Ma, the Arctic was much warmer than it is at the present day (with summer temperatures some 8 °C warmer than today). That

8586-429: The Americas. He stated that the bones that Buffon previously described from North America were not of elephants but another animal that he referred to as the " mastodonte ," or the " animal of Ohio ." He reinforced the idea that the extinct "mastodon" was an animal close in relationship to elephants that differed by jaws with large tubercles. He suggested that "mammoth" and "carnivorous elephant" be discontinued as names for

8745-567: The Aquitanian and Burdigalian Stages), the apes first evolved, began diversifying, and became widespread throughout the Old World . Around the end of this epoch, the ancestors of humans had split away from the ancestors of the chimpanzees and had begun following their own evolutionary path during the final Messinian Stage (7.5–5.3 Ma) of the Miocene. As in the Oligocene before it, grasslands continued to expand, and forests to dwindle. In

8904-680: The Big Bone Lick locality. He stated that the tusks were similar to elephants while the molars were completely different because they were covered with enamel and had a double row of high conical cusp processes. Kerr was unsure about the taxonomic affinities of the molars and referenced that Thomas Pennant supposed that they belong to an unknown species within the genus Elephas , giving the common name "American elephant." German naturalist Johann Friedrich Blumenbach also followed up with more taxonomic descriptions of fossil proboscideans in 1799. The first fossil species, recovered from Germany,

9063-654: The Blancan, and M. raki specifically is thought to not be synonymous with M. pacificum . M. americanum (known popularly as an "American mastodon" or simply "mastodon") is also stratigraphically recorded first from the early Blancan of the Ringold Formation , Washington . The age of the formation where the mammutid specimen was found dates to about 3.75 Ma. It is also known from multiple other Blancan sites such as Fish Springs Flat in Nevada. From

9222-710: The Central Paratethys, cut off from sources of freshwater input by its separation from the Eastern Paratethys. From 13.36 to 12.65 Ma, the Central Paratethys was characterised by open marine conditions, before the reopening of the Bârlad Strait resulted in a shift to brackish-marine conditions in the Central Paratethys, causing the Badenian-Sarmatian Extinction Event. As a result of the Bârlad Strait's reopening,

9381-837: The Early to the Middle Miocene. Europe's large mammal diversity significantly declined during the Late Miocene. In the Early Miocene, several Oligocene groups were still diverse, including nimravids , entelodonts , and three-toed equids. As in the previous Oligocene Epoch, oreodonts were still diverse, only to disappear in the earliest Pliocene. During the later Miocene mammals were more modern, with easily recognizable canids , bears , red pandas , procyonids , equids , beavers , deer , camelids , and whales , along with now-extinct groups like borophagine canids , certain gomphotheres , three-toed horses , and hornless rhinos like Teleoceras and Aphelos . The late Miocene also marks

9540-595: The Earth's climate became cooler and drier, as well as more seasonal, marking a transition between the relatively warm Miocene to the cooler Pleistocene . However, the beginning of the Pliocene was marked by an increase in global temperatures relative to the cooler Messinian . This increase was related to the 1.2 million year obliquity amplitude modulation cycle . By 3.3-3.0 Ma, during the Mid-Piacenzian Warm Period (mPWP), global average temperature

9699-402: The East Antarctic Ice Sheet (EAIS) was highly dynamic during the Early Miocene. The Miocene began with the Early Miocene Cool Event (Mi-1) around 23 million years ago, which marked the start of the Early Miocene Cool Interval (EMCI). This cool event occurred immediately after the Oligocene-Miocene Transition (OMT) during a major expansion of Antarctica's ice sheets, but was not associated with

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9858-399: The East Asian Winter Monsoon (EAWM) became stronger synchronously with a southward shift of the subarctic front. Greenland may have begun to have large glaciers as early as 8 to 7 Ma, although the climate for the most part remained warm enough to support forests there well into the Pliocene. Zhejiang, China was noticeably more humid than today. In the Great Rift Valley of Kenya , there

10017-427: The Elephantimorpha is monophyletic if the primitive Elephantiformes genus Phiomia was truly ancestral to both the Elephantida and Mammutida. An alternate hypothesis suggests that the Elephantimorpha is diphyletic because Phiomia is ancestral to gomphotheres while Palaeomastodon is ancestral to mammutids. The earliest undisputed mammutid genus Losodokodon is recorded in Kenya , Africa and firmly establishes

10176-418: The Hudson River in New York in fall of 1780. The workers found four molars in addition to another that was broken and thrown away. They also uncovered bones, including vertebrae that broke shortly thereafter. Annan expressed his confusion at what the animal could be but speculated based on its "grinders" that it was carnivorous in diet. He speculated also that it was probably extinct due to some catastrophe within

10335-411: The LMC; extratropical sea surface temperatures dropped substantially by approximately 7–9 °C. 41 kyr obliquity cycles became the dominant orbital climatic control 7.7 Ma and this dominance strengthened 6.4 Ma. Benthic δ O values show significant glaciation occurred from 6.26 to 5.50 Ma, during which glacial-interglacial cycles were governed by the 41 kyr obliquity cycle. A major reorganisation of

10494-405: The Late Cretaceous, are known from the Miocene of Patagonia, represented by the mole-like Necrolestes . The youngest known representatives of metatherians (the broader grouping to which marsupials belong) in Europe, Asia and Africa are known from the Miocene, including the European herpetotheriid Amphiperatherium , the peradectids Siamoperadectes and Sinoperadectes from Asia, and

10653-591: The Late Miocene, the Earth's climate began to display a high degree of similarity to that of the present day . The 173 kyr obliquity modulation cycle governed by Earth's interactions with Saturn became detectable in the Late Miocene. By 12 Ma, Oregon was a savanna akin to that of the western margins of the Sierra Nevada of northern California . Central Australia became progressively drier, although southwestern Australia experienced significant wettening from around 12 to 8 Ma. The South Asian Winter Monsoon (SAWM) underwent strengthening ~9.2–8.5 Ma. From 7.9 to 5.8 Ma,

10812-511: The Miocene Epoch was mostly supported by the two newly formed biomes , kelp forests and grasslands . Grasslands allow for more grazers, such as horses , rhinoceroses , and hippos . Ninety-five percent of modern plants existed by the end of this epoch . Modern bony fish genera were established. A modern-style latitudinal biodiversity gradient appeared ~15 Ma. The coevolution of gritty , fibrous, fire-tolerant grasses and long-legged gregarious ungulates with high-crowned teeth , led to

10971-449: The Miocene. The largest form among them was a gigantic caiman Purussaurus which inhabited South America. Another gigantic form was a false gharial Rhamphosuchus , which inhabited modern age India . A strange form, Mourasuchus also thrived alongside Purussaurus . This species developed a specialized filter-feeding mechanism, and it likely preyed upon small fauna despite its gigantic size. The youngest members of Sebecidae ,

11130-413: The North American Great Plains and in Argentina . The global trend was towards increasing aridity caused primarily by global cooling reducing the ability of the atmosphere to absorb moisture, particularly after 7 to 8 million years ago. Uplift of East Africa in the late Miocene was partly responsible for the shrinking of tropical rain forests in that region, and Australia got drier as it entered

11289-512: The North American species of Zygolophodon and Mammut . They synonymized P. adamsi and P. sellardsi with Mammut matthewi and emended M. nevadanus and M. pacificus to M. nevadanum and M. pacificum , respectively. They also said that they were uncertain of the taxonomic status of M. furlongi , specifically whether or not it was a variant of sexual dimorphism of Z. proavus . Some authors have considered M. nevadanum to be synonymous with M. matthewi while others had retained validity of

11448-656: The Oligocene–Miocene transgression. As the southern Andes rose in the Middle Miocene (14–12 million years ago) the resulting rain shadow originated the Patagonian Desert to the east. Far northern Australia was monsoonal during the Miocene. Although northern Australia is often believed to have been much wetter during the Miocene, this interpretation may be an artefact of preservation bias of riparian and lacustrine plants; this finding has itself been challenged by other papers. Western Australia, like today,

11607-510: The Pliocene also included the Gelasian Stage, which lasted from 2.59 to 1.81 Ma, and is now included in the Pleistocene. As with other older geologic periods, the geological strata that define the start and end are well-identified but the exact dates of the start and end of the epoch are slightly uncertain. The boundaries defining the Pliocene are not set at an easily identified worldwide event but rather at regional boundaries between

11766-628: The Pliocene contains the Dacian (roughly equal to the Zanclean) and Romanian (roughly equal to the Piacenzian and Gelasian together) stages. As usual in stratigraphy, there are many other regional and local subdivisions in use. In Britain , the Pliocene is divided into the following stages (old to young): Gedgravian, Waltonian , Pre-Ludhamian, Ludhamian, Thurnian, Bramertonian or Antian, Pre-Pastonian or Baventian, Pastonian and Beestonian . In

11925-566: The Pliocene were such proboscideans as Deinotherium , Anancus , and Mammut borsoni , ) though proboscidean diversity declined significantly during the Late Pliocene. Hyraxes migrated north from Africa. Horse diversity declined, while tapirs and rhinos did fairly well. Bovines and antelopes were successful; some camel species crossed into Asia from North America. Hyenas and early saber-toothed cats appeared, joining other predators including dogs, bears, and weasels. Africa

12084-617: The Qiongdongnan Basin in the northern South China Sea indicates the Pearl River was a major source of sediment flux into the sea during the Early Miocene and was a major fluvial system as in the present. During the Oligocene and Early Miocene, the coast of northern Brazil, Colombia, south-central Peru , central Chile and large swathes of inland Patagonia were subject to a marine transgression . The transgressions in

12243-546: The Western Atlantic, assemblages of bivalves exhibited remarkable stasis with regards to their basal metabolic rates throughout the various climatic changes of the Pliocene. The Pliocene was a high water mark for species diversity among Caribbean corals. From 5 to 2 Ma, coral species origination rates were relatively high in the Caribbean, although a noticeable extinction event and drop in diversity occurred at

12402-483: The abundance of C 4 plants across the region. In the Loess Plateau , δ13C values of occluded organic matter increased by 2.5% while those of pedogenic carbonate increased by 5% over the course of the Late Miocene and Pliocene, indicating increased aridification. Further aridification of Central Asia was caused by the development of Northern Hemisphere glaciation during the Late Pliocene. A sediment core from

12561-497: The activity of the Columbia River Basalts and enhanced by decreased albedo from the reduction of deserts and expansion of forests. Climate modelling suggests additional, currently unknown, factors also worked to create the warm conditions of the MMCO. The MMCO saw the expansion of the tropical climatic zone to much larger than its current size. The July ITCZ, the zone of maximal monsoonal rainfall, moved to

12720-462: The ancestors of modern elephants at least 27–25 million years ago, during the Oligocene . Like other members of Mammutidae, the molar teeth of mastodons have zygodont morphology (where parallel pairs of cusps are merged into sharp ridges), which strongly differ from those of elephantids. In comparison to its likely ancestor Zygolophodon , Mammut is characterized by particularly long and upward curving upper tusks, reduced or absent tusks on

12879-472: The aridity of the former. Unequivocally-recognizable dabbling ducks , plovers , typical owls , cockatoos and crows appear during the Miocene. By the epoch's end, all or almost all modern bird groups are believed to have been present; the few post-Miocene bird fossils which cannot be placed in the evolutionary tree with full confidence are simply too badly preserved, rather than too equivocal in character. Marine birds reached their highest diversity ever in

13038-638: The beginning of the Miocene, the northern margin of the Arabian plate, then part of the African landmass, collided with Eurasia; as a result, the Tethys seaway continued to shrink and then disappeared as Africa collided with Eurasia in the Turkish – Arabian region. The first step of this closure occurred 20 Ma, reducing water mass exchange by 90%, while the second step occurred around 13.8 Ma, coincident with

13197-465: The bones were discovered by Native Americans (probably Abenaki hunter-warriors). He came to the conclusion that the femur and tusk belonged to an elephant while the molars (or cheek teeth) came from a separate giant hippopotamus . In Shawnee tradition, the proboscideans roamed in herds and were hunted by giants, who both eventually died out. The accounts told by the Shawnee individuals in 1762 are

13356-617: The climate cooled. Venomous snake genera continued to increase as more rodents and birds evolved. Rattlesnakes first appeared in the Pliocene. The modern species Alligator mississippiensis , having evolved in the Miocene, continued into the Pliocene, except with a more northern range; specimens have been found in very late Miocene deposits of Tennessee . Giant tortoises still thrived in North America, with genera like Hesperotestudo . Madtsoid snakes were still present in Australia. The amphibian order Allocaudata became extinct. In

13515-577: The course of this epoch . The youngest representatives of Choristodera , an extinct order of aquatic reptiles that first appeared in the Middle Jurassic , are known from the Miocene of Europe, belonging to the genus Lazarussuchus , which had been the only known surviving genus of the group since the beginning of the Eocene. The last known representatives of the archaic primitive mammal order Meridiolestida , which dominated South America during

13674-462: The earliest Miocene (~23-20 Ma) of Africa after Losodokodon . Eozygodon was subsequently succeeded by Zygolophodon by the early Miocene, and the latter dispersed into Eurasia by around 19-18 million years ago, and into North America by the middle Miocene. The dispersal of mammutids between Africa and Eurasia may have occurred multiple times. The Mammutidae eventually went extinct in Africa prior to

13833-415: The earliest presence of mammutids in the late Oligocene (~27-24 Ma). The Mammutidae, like other Paleogene proboscideans, was therefore an endemic radiation within the continent akin to other endemic mammals like arsinoitheres , hyracoids , and catarrhine primates plus non-endemics such as anthracotheres and hyaenodonts . In the early Neogene phase of evolution, Eozygodon made an appearance in

13992-463: The early Hemphillian , or 8.0-7.1 Ma. Historically, North American paleontologists considered that North American Zygolophodon evolved into Mammut in an endemic fashion while European workers generally thought that Mammut was a Eurasian immigrant that replaced North American Zygolophodon during the Miocene or Pliocene . Current evidence supports an endemic origin of North American Mammut from Zygolophodon without later migration because of

14151-619: The early to mid Miocene (23–15 Ma). Oceans cooled partly due to the formation of the Antarctic Circumpolar Current , and about 15 million years ago the ice cap in the southern hemisphere started to grow to its present form. The Greenland ice cap developed later, in the Middle Pliocene time, about 3 million years ago. Pliocene The Pliocene ( / ˈ p l aɪ . ə s iː n , ˈ p l aɪ . oʊ -/ PLY -ə-seen, PLY -oh- ; also Pleiocene )

14310-475: The early-mid Pliocene (5 Ma – 3 Ma), after three-million-year intervals with modern or glacial ice volume became longer and collapse occurs only at times when warmer global temperature coincide with strong austral summer insolation anomalies. Continents continued to drift , moving from positions possibly as far as 250 km from their present locations to positions only 70 km from their current locations. South America became linked to North America through

14469-515: The end of the Miocene due to increased habitat uniformity. The expansion of grasslands in North America also led to an explosive radiation among snakes. Previously, snakes were a minor component of the North American fauna, but during the Miocene, the number of species and their prevalence increased dramatically with the first appearances of vipers and elapids in North America and the significant diversification of Colubridae (including

14628-422: The end of the Miocene. The Paratethys underwent a significant transgression during the early Middle Miocene. Around 13.8 Ma, during a global sea level drop, the Eastern Paratethys was cut off from the global ocean by the closure of the Bârlad Strait, effectively turning it into a saltwater lake. From 13.8 to 13.36 Ma, an evaporite period similar to the later Messinian salinity crisis in the Mediterranean ensued in

14787-506: The end of this interval. Oceans continued to be relatively warm during the Pliocene, though they continued cooling. The Arctic ice cap formed , drying the climate and increasing cool shallow currents in the North Atlantic. Deep cold currents flowed from the Antarctic. The formation of the Isthmus of Panama about 3.5 million years ago cut off the final remnant of what was once essentially a circum-equatorial current that had existed since

14946-637: The enigmatic Saint Bathans Mammal . Microbial life in the igneous crust of the Fennoscandian Shield shifted from being dominated by methanogens to being primarily composed of sulphate-reducing prokaryotes . The change resulted from fracture reactivation during the Pyrenean-Alpine orogeny, enabling sulphate-reducing microbes to permeate into the Fennoscandian Shield via descending surficial waters. Diatom diversity

15105-461: The evolution of both groups into modern representatives. The early Miocene Saint Bathans Fauna is the only Cenozoic terrestrial fossil record of the landmass, showcasing a wide variety of not only bird species, including early representatives of clades such as moa , kiwi and adzebills , but also a diverse herpetofauna of sphenodontians , crocodiles and turtles as well as a rich terrestrial mammal fauna composed of various species of bats and

15264-499: The expansion of grasslands not to a CO 2 drop but to the increasing seasonality and aridity, coupled with a monsoon climate, which made wildfires highly prevalent compared to before. The Late Miocene expansion of grasslands had cascading effects on the global carbon cycle, evidenced by the imprint it left in carbon isotope records. Cycads between 11.5 and 5 million years ago began to rediversify after previous declines in variety due to climatic changes, and thus modern cycads are not

15423-718: The extinction of the last-surviving members of the hyaenodonts . Islands began to form between South and North America in the Late Miocene, allowing ground sloths like Thinobadistes to island-hop to North America. The expansion of silica-rich C 4 grasses led to worldwide extinctions of herbivorous species without high-crowned teeth . Mustelids diversified into their largest forms as terrestrial predators like Ekorus , Eomellivora , and Megalictis and bunodont otters like Enhydriodon and Sivaonyx appeared. Eulipotyphlans were widespread in Europe, being less diverse in Southern Europe than farther north due to

15582-629: The findings of marine invertebrate fossils of both Atlantic and Pacific affinity in La Cascada Formation . Connection would have occurred through narrow epicontinental seaways that formed channels in a dissected topography . The Antarctic Plate started to subduct beneath South America 14 million years ago in the Miocene, forming the Chile Triple Junction . At first the Antarctic Plate subducted only in

15741-769: The first half of the 19th century. Today, the genera that include species formerly classified into Mastodon include Gomphotherium ( G. angustidens , G. pyrenaicum , G. productum , G. libycum , G. subtapiroideum , G. steinheimense ), Zygolophodon ( Z. turicensis , Z. proavus ), Cuvieronius ( C. hyodon ), Stegodon ( S. elephantoides ), Stegolophodon ( S. latidens , S. cautleyi ), Anancus ( A. avernensis , A. sivalensis , A. perimensis ), Tetralophodon ( T. longirostris ), Choerolophodon ( C. pentelici ), Stegomastodon ( S. mirificus ), Rhynchotherium (" R. " euhypodon ), Stenobelodon ( S. floridanus ), and Notiomastodon ( N. platensis ). In 1830, American naturalist John Davidson Godman created

15900-549: The first time since the Cretaceous , with North American rodents and primates mixing with southern forms. Litopterns and the notoungulates , South American natives, were mostly wiped out, except for the macrauchenids and toxodonts , which managed to survive. Small weasel-like carnivorous mustelids , coatis and short-faced bears migrated from the north. Grazing glyptodonts , browsing giant ground sloths and smaller caviomorph rodents , pampatheres , and armadillos did

16059-440: The genus Tetracaulodon plus its species T. Mastodontoideum based on what he determined to be differences between it and Mastodon based on the skull and dentition. Both Richard Harlan and William Cooper pointed out that except for the tusks, all other characteristics of the specimens were consistent with M. giganteum . They therefore argued that there was no reason to assume that the tusks were not just individual variations,

16218-668: The globe. American statesman Thomas Jefferson stated his thoughts on Notes on the State of Virginia (published by 1785) that the fossil proboscideans may have been carnivorous, still exist in the northern parts of North America, and are related to mammoths whose remains were found in Siberia. Jefferson referenced the theory of American social degeneracy by Georges-Louis Leclerc, Comte de Buffon , countering it by using extant and extinct animal measurements, including those of "mammoths," as proof that North America faunas were not "degenerative" in size. Semonin pointed out that social degeneracy

16377-606: The gradual appearance of Mammut morphologies and a lack of solid evidence that Mammut sensu stricto (in a strict sense) ever dispersed outside of North America. M. matthewi is recorded from the late Hemphillian to early Blancan stages. Mammutid specimens of the Hemphillian and Blancan had typically previously been assigned to M. matthewi , but this is seemingly the result of overreliance on stratigraphic positions to define taxa. M. vexillarius , M. raki , and M. cosoensis are definitively recorded from

16536-450: The historic plus taxonomically correct name Mammut over Mastodon . He continued prioritizing Mammut in 1945, stating that people were generally aware of its taxonomic priorities over Mastodon and that people had refused to use it. He stated that he did not want to either but reluctantly set aside his personal preferences to follow taxonomic rules. In 1921, Osborn created the species name Mastodon matthewi based on distinct molars from

16695-411: The human lineage) appeared in Africa at the very end of the Miocene, including Sahelanthropus , Orrorin , and an early form of Ardipithecus ( A. kadabba ). The chimpanzee–human divergence is thought to have occurred at this time. The evolution of bipedalism in apes at the end of the Miocene instigated an increased rate of faunal turnover in Africa. In contrast, European apes met their end at

16854-413: The influence of seasonal variation. More recent research has emphasized the variability selection hypothesis, which proposes that variability in climate fostered development of hominin traits. Improved climate proxies show that the Pliocene climate of east Africa was highly variable, suggesting that adaptability to varying conditions was more important in driving hominin evolution than the steady pressure of

17013-606: The lake levels of the Eastern Paratethys dropped as it once again became a sea. The Fram Strait opened during the Miocene and acted as the only throughflow for Atlantic Water into the Arctic Ocean until the Quaternary period. Due to regional uplift of the continental shelf, this water could not move through the Barents Seaway in the Miocene. The modern day Mekong Delta took shape after 8 Ma. Geochemistry of

17172-687: The land bridge between South America and North America was absent, although South America was approaching the western subduction zone in the Pacific Ocean , causing both the rise of the Andes and a southward extension of the Meso-American peninsula. Mountain building took place in western North America , Europe , and East Asia . Both continental and marine Miocene deposits are common worldwide with marine outcrops common near modern shorelines. Well studied continental exposures occur in

17331-557: The last Eurasian mammutid, became extinct during the earliest Pleistocene , around 2.5-2 million years ago. The oldest evidence of mammutids in North America is of a fragmentary molar of Zygolophodon sp. from Massacre Lake , Nevada, dating to 16.5-16.4 Ma (during the Hemingfordian stage of the North American land mammal ages (NALMA)). The only definitively defined species of Zygolophodon from North America

17490-580: The late Miocene, the connections between the Atlantic and Mediterranean closed, causing the Mediterranean Sea to almost completely evaporate. This event is referred to as the " Messinian salinity crisis ". Then, at the Miocene–Pliocene boundary, the Strait of Gibraltar opened, and the Mediterranean refilled. That event is referred to as the " Zanclean flood ". Also during the early Miocene (specifically

17649-466: The late Miocene. Mammut as currently defined sensu lato (in a broad sense) is most likely polyphyletic (comprising several unrelated groups). This is because the inclusion of Eurasian mammutid species into Mammut implies that they share a common origin with North American Mammut , but this relationship has been doubted. As a result, these Eurasian species may belong to either other existing mammutid genera or entirely new genera. "Mammut" borsoni ,

17808-612: The locality in 1801, where he first sketched the fossils then purchased excavation privileges and full ownership of the fossils from Masten and borrowed a loan from the American Philosophical Society (APS) in Philadelphia , Pennsylvania . In addition to the first skeleton, the second was excavated using a mill-like device to drain a 12 ft (3.7 m) deep marl pit. Peale assembled a complete skeleton in his Philadelphia Museum in 1804, and its exhibit

17967-487: The locality of Truth or Consequences , New Mexico based on differences on the heel and M 3 tooth from M. americanus , otherwise having proportions similar to it. In 1936, Chester Stock published the species name Pliomastodon nevadanus based on fossils from the Thousand Creek Beds of northwestern Nevada. In 1937, John R. Schultz created the species name Pliomastodon? cosoensis , naming it after

18126-909: The lower jaw, as well as the shortening of the mandibular symphysis (the frontmost part of the lower jaw), the latter two traits also having evolved in parallel separately in elephantids. Mastodons had an overall stockier skeletal build, a lower-domed skull, and a longer tail compared to elephantids. Fully grown male M. americanum are thought to have been have been 275 cm (9.02 ft) to 305 cm (10.01 ft) at shoulder height and from 6.8 t (6.7 long tons; 7.5 short tons) to 9.2 t (9.1 long tons; 10.1 short tons) in body mass on average. The size estimates suggest that American mastodon males were on average heavier than any living elephant species; they were typically larger than Asian elephants and African forest elephants of both sexes but shorter than male African bush elephants . M. americanum , known as an "American mastodon" or simply "mastodon," had

18285-471: The molars. The naturalist also created the second species name Mastodon angustidens and gave it the informal name "narrow-toothed mastodon," diagnosing it as having narrower molars, smaller sizes compared to M. giganteum , and range distributions in Europe and South America. Cuvier also erected several other species of Mastodon originating from other continents in 1824. Despite Cuvier's genus name being younger than multiple other genus names, Mastodon became

18444-423: The most commonly used genus name for the 19th century. " Mastodon " was riddled with major taxonomic problems since species now determined as belonging to other proboscidean genera were classified to Mastodon on the basis of similar dentitions to that of " Mastodon giganteum " (= Mammut americanum ), effectively making it a wastebasket taxon . Various fossil proboscidean species were classified into Mastodon in

18603-510: The neighboring fields. They were observed by a large amount of spectators and uncovered relatively complete fossil evidence of M. americanum . The skeleton was exhibited in New York City and other New England towns then was acquired by John Collins Warren for study. After Warren's death in 1856, the skeleton was sent to Warren's family but was traded to Harvard Medical School for John Warren's skeleton. The "Warren mastodon", under

18762-547: The north, increasing precipitation over southern China whilst simultaneously decreasing it over Indochina during the EASM. Western Australia was at this time characterised by exceptional aridity. In Antarctica, average summer temperatures on land reached 10 °C. In the oceans, the lysocline shoaled by approximately half of a kilometre during warm phases that corresponded to orbital eccentricity maxima. The MMCO ended around 14 million years ago, when global temperatures fell in

18921-555: The northern South China Sea shows an increase in dust storm activity during the middle Pliocene. The South Asian Summer Monsoon (SASM) increased in intensity after 2.95 Ma, likely because of enhanced cross-equatorial pressure caused by the reorganisation of the Indonesian Throughflow. In the south-central Andes , an arid period occurred from 6.1 to 5.2 Ma, with another occurring from 3.6 to 3.3 Ma. These arid periods are coincident with global cold periods, during which

19080-422: The northern hemisphere. The Miocene faunal stages from youngest to oldest are typically named according to the International Commission on Stratigraphy : Regionally, other systems are used, based on characteristic land mammals; some of them overlap with the preceding Oligocene and following Pliocene Epochs: Continents continued to drift toward their present positions. Of the modern geologic features, only

19239-698: The now-separated Atlantic Ocean. Africa 's collision with Europe formed the Mediterranean Sea , cutting off the remnants of the Tethys Ocean . The border between the Miocene and the Pliocene is also the time of the Messinian salinity crisis . During the Late Pliocene, the Himalayas became less active in their uplift, as evidenced by sedimentation changes in the Bengal Fan . The land bridge between Alaska and Siberia ( Beringia )

19398-404: The oldest genus name, making Mastodon , Tetracaulodon , and Missourium classified as junior synonyms. He also established M. americanum as the type species. The genus name Mastodon was subsequently abandoned by many American paleontologists in favor of Mammut within the early 20th century. In 1942, American paleontologist George Gaylord Simpson said that for his study, he prioritized

19557-524: The oldest known documented interpretations of the " Ohio " fossils, although the traditions may have had been told for generations. In 1767, Peter Collinson credited Irish trader George Croghan for having sent him and Benjamin Franklin fossil evidence of the mysterious proboscideans, using them for his studies. He concluded that the peculiar grinders (the molars) were built for herbivorous diets of branches of trees and shrubs as well as other vegetation,

19716-512: The onset of continental glaciation in the Arctic, suggesting that vegetation changes in Australia during the Pliocene behaved similarly to during the Late Pleistocene and were likely characterised by comparable cycles of aridity and humidity. The equatorial Pacific Ocean sea surface temperature gradient was considerably lower than it is today. Mean sea surface temperatures in the east were substantially warmer than today but similar in

19875-400: The opposite, migrating to the north and thriving there. The marsupials remained the dominant Australian mammals, with herbivore forms including wombats and kangaroos , and the huge Diprotodon . Carnivorous marsupials continued hunting in the Pliocene, including dasyurids , the dog-like thylacine and cat-like Thylacoleo . The first rodents arrived in Australia. The modern platypus ,

20034-523: The origin of many modern genera such as Nerodia , Lampropeltis , Pituophis and Pantherophis ). Arthropods were abundant, including in areas such as Tibet where they have traditionally been thought to be undiverse. Neoisopterans diversified and expanded into areas they previously were absent from, such as Madagascar and Australia. In the oceans, brown algae , called kelp , proliferated, supporting new species of sea life, including otters , fish and various invertebrates . Corals suffered

20193-628: The position of the Southern Hemisphere westerlies shifted northward and disrupted the South American Low Level Jet, which brings moisture to southeastern South America. From around 3.8 Ma to about 3.3 Ma, North Africa experienced an extended humid period. In northwestern Africa, tropical forests extended up to Cape Blanc during the Zanclean until around 3.5 Ma. During the Piacenzian, from about 3.5 to 2.6 Ma,

20352-463: The possible herpetotheriid Morotodon from the late Early Miocene of Uganda. Approximately 100 species of apes lived during this time , ranging throughout Africa, Asia and Europe and varying widely in size, diet, and anatomy. Due to scanty fossil evidence it is unclear which ape or apes contributed to the modern hominid clade, but molecular evidence indicates this ape lived between 18 and 13 million years ago. The first hominins ( bipedal apes of

20511-605: The previously established species " Elephas americanus " and argued that the species was different from elephants and mammoths and cannot be found amongst living animals due to extinction from catastrophism . The proboscidean species was subject to several other species names given by other taxonomists within the earliest 18th century as well as the genus name Harpagmotherium by the Russian naturalist Gotthelf Fischer von Waldheim in 1808. In 1806, Cuvier wrote multiple extended research articles on fossil proboscideans of Eurasia and

20670-493: The promotion of the "mastodon" skeleton made it a symbol of the strength of American nationalism and that "mammoth" as a term became associated with gigantism. Decades later, the museum bankrupted, and the first skeleton's specimens were sold to some German spectators in around 1848, who eventually sold it to Hessisches Landesmuseum Darmstadt in Germany where it is now displayed. The second skeleton's specimens landed eventually at

20829-514: The recent", referring to the essentially modern marine mollusc fauna. In the official timescale of the ICS , the Pliocene is subdivided into two stages . From youngest to oldest they are: The Piacenzian is sometimes referred to as the Late Pliocene, whereas the Zanclean is referred to as the Early Pliocene. In the system of In the Paratethys area (central Europe and parts of western Asia)

20988-499: The region was forested at irregular intervals and contained a significant Saharan palaeoriver until 3.35 Ma, when trade winds began to dominate over fluvial transport of pollen. Around 3.26 Ma, a strong aridification event that was followed by a return to more humid conditions, which was itself followed by another aridification around 2.7 Ma. From 2.6 to 2.4 Ma, vegetation zones began repeatedly shifting latitudinally in response to glacial-interglacial cycles. The climate of eastern Africa

21147-506: The request of American paleontologist Henry Fairfield Osborn , was purchased by the American financier J. P. Morgan for $ 30,000 in 1906 and donated to the American Museum of Natural History where it is exhibited today. In the 1790s, the " American incognitum " was subject to research by multiple taxonomists. Scottish writer Robert Kerr erected the species name Elephas americanus in 1792 based on fossil tusks and "grinders" from

21306-419: The scene. Bears, dogs and weasels (originally from North America) joined cats, hyenas and civets as the African predators, forcing hyenas to adapt as specialized scavengers. Most mustelids in Africa declined as a result of increased competition from the new predators, although Enhydriodon omoensis remained an unusually successful terrestrial predator. South America was invaded by North American species for

21465-582: The seas of the Miocene, kelp forests made their first appearance and soon became one of Earth's most productive ecosystems. The plants and animals of the Miocene were recognizably modern. Mammals and birds were well established. Whales , pinnipeds , and kelp spread. The Miocene is of particular interest to geologists and palaeoclimatologists because major phases of the geology of the Himalaya occurred during that epoch, affecting monsoonal patterns in Asia, which were interlinked with glacial periods in

21624-714: The southernmost tip of Patagonia, meaning that the Chile Triple Junction lay near the Strait of Magellan . As the southern part of Nazca Plate and the Chile Rise became consumed by subduction the more northerly regions of the Antarctic Plate begun to subduct beneath Patagonia so that the Chile Triple Junction advanced to the north over time. The asthenospheric window associated to the triple junction disturbed previous patterns of mantle convection beneath Patagonia inducing an uplift of ca. 1 km that reversed

21783-477: The species and that it receive a new genus name instead. Cuvier said that for " mastodonte ," he derived the name's etymology (compound μαστός ( mastós , "breast") + ὀδούς ( odoús , "tooth") from Ancient Greek to mean "nipple tooth," since he thought that it expressed the characteristic form of the teeth. In 1817, the French naturalist officially established the genus name Mastodon , reaffirming that it

21942-406: The species name. Several mammutid species outside of North America are classified to Mammut (or " Pliomastodon "), namely M. borsoni , M. obliquelophus , M. zhupengensis , and M. lufugense (possibly synonymous with M. obliquelophus ). Recent research such as that of von Koenigswald et al. in 2023 warned that the genus Mammut should be carefully used for non-North American species. Mammut

22101-541: The species was distinguished from other animals of the prehistoric world based on the unusual shapes of the large molars. The genus name "Mammut" refers to the German translation for "mammoth." The naming of the genus Mammut in 1799 makes it the second or third genus to be recognized with taxonomic authority given that Megalonyx had been named the same year. French naturalist Georges Cuvier also described known fossil proboscidean species back in 1796, although his account

22260-400: The surrounding environment. Anthropologists tended to focus on intrinsic models while geologists and vertebrate paleontologists tended to put greater emphasis on habitats. Alternatives to the savanna hypothesis include the woodland/forest hypothesis, which emphasizes the evolution of hominins in closed habitats, or hypotheses emphasizing the influence of colder habitats at higher latitudes or

22419-578: The teeth both dissolved before they could be further observed, however. In 1739, a French military expedition under the command of Charles III Le Moyne (known also as "Longueil") explored the locality of " Big Bone Lick " (located in what is now the US state of Kentucky ) and gathered fossil bones and teeth there. The French naturalist Louis Jean-Marie Daubenton examined the fossil collection brought by Longueuil and compared it with specimens of extant elephants and Siberian mammoths in 1762. Daubenton said that

22578-514: The warmer Miocene and the relatively cooler Pleistocene. The upper boundary was set at the start of the Pleistocene glaciations. Charles Lyell (later Sir Charles) gave the Pliocene its name in Principles of Geology (volume 3, 1833). The word pliocene comes from the Greek words πλεῖον ( pleion , "more") and καινός ( kainos , "new" or "recent") and means roughly "continuation of

22737-604: The west coast of South America are thought to be caused by a regional phenomenon while the steadily rising central segment of the Andes represents an exception. While there are numerous registers of Oligocene–Miocene transgressions around the world it is doubtful that these correlate. It is thought that the Oligocene–Miocene transgression in Patagonia could have temporarily linked the Pacific and Atlantic Oceans, as inferred from

22896-505: The west. This condition has been described as a permanent El Niño state, or “El Padre.” Several mechanisms have been proposed for this pattern, including increased tropical cyclone activity . The extent of the West Antarctic Ice Sheet oscillated at the 40 kyr period of Earth's obliquity. Ice sheet collapse occurred when the global average temperature was 3 °C warmer than today and carbon dioxide concentration

23055-423: Was Allodesmus . A ferocious walrus , Pelagiarctos may have preyed upon other species of pinnipeds including Allodesmus . Furthermore, South American waters witnessed the arrival of Megapiranha paranensis , which were considerably larger than modern age piranhas . New Zealand 's Miocene fossil record is particularly rich. Marine deposits showcase a variety of cetaceans and penguins , illustrating

23214-470: Was 2–3 °C higher than today, while carbon dioxide levels were the same as today (400 ppm). Global sea level was about 25 m higher, though its exact value is uncertain. The northern hemisphere ice sheet was ephemeral before the onset of extensive glaciation over Greenland that occurred in the late Pliocene around 3 Ma. The formation of an Arctic ice cap is signaled by an abrupt shift in oxygen isotope ratios and ice-rafted cobbles in

23373-624: Was a gradual and progressive trend of increasing aridification, though it was not unidirectional, and wet humid episodes continued to occur. Between 7 and 5.3 Ma, temperatures dropped sharply again in the Late Miocene Cooling (LMC), most likely as a result of a decline in atmospheric carbon dioxide and a drop in the amplitude of Earth's obliquity, and the Antarctic ice sheet was approaching its present-day size and thickness. Ocean temperatures plummeted to near-modern values during

23532-531: Was an offensive concept to Anglo-American naturalists and that the American proboscidean fossils were used as political tools to inspire American nationalism and counter against the theory of American degeneracy. In 1799, laborers recovered a thighbone while digging a marl pit at John Masten's farm in Newburgh , New York, and subsequent excavations were observed by a crowd of over a hundred people. American painter and exhibitionist Charles Willson Peale visited

23691-464: Was arid, particularly so during the Middle Miocene. Climates remained moderately warm, although the slow global cooling that eventually led to the Pleistocene glaciations continued. Although a long-term cooling trend was well underway, there is evidence of a warm period during the Miocene when the global climate rivalled that of the Oligocene . The climate of the Miocene has been suggested as

23850-511: Was at 400 ppmv. This resulted in open waters in the Ross Sea . Global sea-level fluctuation associated with ice-sheet collapse was probably up to 7 meters for the west Antarctic and 3 meters for the east Antarctic. Model simulations are consistent with reconstructed ice-sheet oscillations and suggest a progression from a smaller to a larger West Antarctic ice sheet in the last 5 million years. Intervals of ice sheet collapse were much more common in

24009-400: Was described as belonging to the newly erected species Elephas primigenius ? (now known as Mammuthus primigenius ). The second was what he considered to be an unknown "colossal land monster of the prehistoric world," considering it to be the "mammoth." He created the genus Mammut and erected the species Mammut ohioticum based on fossil bones dug up from Ohio in North America. He said that

24168-486: Was dominated by hoofed animals, and primates continued their evolution, with australopithecines (some of the first hominins ) and baboon-like monkeys such as the Dinopithecus appearing in the late Pliocene. Rodents were successful, and elephant populations increased. Cows and antelopes continued diversification and overtook pigs in numbers of species. Early giraffes appeared. Horses and modern rhinos came onto

24327-452: Was first flooded near the start of the Pliocene, allowing marine organisms to spread between the Arctic and Pacific Oceans. The bridge would continue to be periodically flooded and restored thereafter. Pliocene marine formations are exposed in northeast Spain , southern California , New Zealand , and Italy . During the Pliocene parts of southern Norway and southern Sweden that had been near sea level rose. In Norway this rise elevated

24486-688: Was inversely correlated with carbon dioxide levels and global temperatures during the Miocene. Most modern lineages of diatoms appeared by the Late Miocene. There is evidence from oxygen isotopes at Deep Sea Drilling Program sites that ice began to build up in Antarctica about 36 Ma during the Eocene . Further marked decreases in temperature during the Middle Miocene at 15 Ma probably reflect increased ice growth in Antarctica. It can therefore be assumed that East Antarctica had some glaciers during

24645-456: Was later published in 1799. He considered that the remains uncovered from Siberia were true "mammoths" that had similar dentitions to extant elephants but had some morphological differences. He mentioned the fossil remains that were brought back by Longueil from Ohio back in 1739 and several researchers from previous decades who noted the unusual molars and thought that they belonged to different animals like hippopotamuses. He followed recognition in

24804-646: Was most intense there. Around this time the Mi3b glacial event (a massive expansion of Antarctic glaciers) occurred. The East Antarctic Ice Sheet (EAIS) markedly stabilised following the MMCT. The intensification of glaciation caused a decoherence of sediment deposition from the 405 kyr eccentricity cycle. The MMWI ended about 11 Ma, when the Late Miocene Cool Interval (LMCI) started. A major but transient warming occurred around 10.8-10.7 Ma. During

24963-677: Was open first to invited members of the American Philosophical Society on December 24 then to the general public on December 25 for an exhibit admission fee in addition to the general admission fee. The special exhibition attracted thousands of visitors, and the skeleton became a US national symbol. Charles Peale's son Rembrandt Peale took the skeleton to Europe used to promote the fossil proboscidean and have it used as support for Jefferson's final rebuttals against Buffon's arguments for supposed inferiority of American faunas. Author Keith Stewart Thomson argued that

25122-706: Was synonymized with Mammut while Miomastodon was synonymized with Zygolophodon by Jeheskel Shoshani and Pascal Tassy in a 1996 appendix, a view that was followed by other authors in later years. In 2019, Alton C. Dooley Jr. et al. established Mammut pacificus based on fossils collected from the Diamond Valley Lake in Hemet , California. They also stated that M. oregonense is a nomen dubium and that further analysis needs to be done to confirm whether or not M. furlongi belongs to Zygolophodon instead. In 2023, Wighart von Koenigswald et al. reviewed

25281-545: Was very similar to what it is today. Unexpectedly, the expansion of grasslands in eastern Africa during this epoch appears to have been decoupled from aridification and not caused by it, as evidenced by their asynchrony. Southwestern Australia hosted heathlands , shrublands , and woodlands with a greater species diversity compared to today during the Middle and Late Pliocene. Three different aridification events occurred around 2.90, 2.59, and 2.56 Ma, and may have been linked to

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