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113-668: The Antarctic plate started to subduct beneath South America 14 million years ago in the Miocene epoch forming the Chile triple junction. At first the Antarctic plate subducted only in 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 and the more northerly regions of

226-459: A Middle Jurassic fossil of the early mammal Didelphis , Lyell told his father that "There was everything but man even as far back as the Oolite." Lyell inaccurately portrayed Lamarckism as a response to the fossil record, and said it was falsified by a lack of progress. He said in the second volume of Principles that the occurrence of this one fossil of the higher mammalia "in these ancient strata,

339-571: A "remarkable manifestation of creative Power" as creating each species separately. He countered Lamarck's views by rejecting continued cooling of the earth in favour of "a fluctuating cycle", a long-term steady-state geohistory as proposed by James Hutton . The fragmentary fossil record already showed "a high class of fishes, close to reptiles" in the Carboniferous period which he called "the first Zoological era", and quadrupeds could also have existed then. In November 1827, after William Broderip found

452-526: 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

565-519: 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

678-561: 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

791-506: A copy of Principles and praising the book as opening a way for bold speculation on "that mystery of mysteries, the replacement of extinct species by others" – by analogy with other intermediate causes , "the origination of fresh species, could it ever come under our cognizance, would be found to be a natural in contradistinction to a miraculous process". Lyell replied: "In regard to the origination of new species, I am very glad to find that you think it probable that it may be carried on through

904-473: 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

1017-435: 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

1130-579: 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

1243-480: 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

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1356-590: A profession, entering Lincoln's Inn in 1820. He completed a circuit through rural England, where he could observe geological phenomena. In 1821 he attended Robert Jameson 's lectures in Edinburgh, and visited Gideon Mantell at Lewes , in Sussex . In 1823 he was elected joint secretary of the Geological Society . As his eyesight began to deteriorate, he turned to geology as a full-time profession. His first paper, "On

1469-582: A profitable mining area, bears Lyell's name; and the Lyell Range in north-west Western Australia is named after him as well. In Southwest Nelson in the South Island of New Zealand, the Lyell Range, Lyell River and the gold mining town of Lyell (now only a camping site) were all named after Lyell. Lyall Bay in Wellington, New Zealand was possibly named after Lyell. The jawless fish Cephalaspis lyelli , from

1582-513: A recent formation of freshwater limestone in Forfarshire", was presented in 1826. By 1827, he had abandoned law and embarked on a geological career that would result in fame and the general acceptance of uniformitarianism, a working out of the ideas proposed by James Hutton a few decades earlier. In 1832, Lyell married Mary Horner in Bonn, daughter of Leonard Horner (1785–1864), also associated with

1695-468: A remarkable series of nearly three hundred manuscript notebooks and diaries. These span Lyell's long scientific career (1825–1874), and offer an unrivalled insight into personal influences, field observations, thoughts and relationships. They were acquired in 2019 by the University of Edinburgh 's Heritage Collections, thanks to a fundraising campaign, with many generous individual and institutional donors from

1808-578: 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

1921-695: 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

2034-627: 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

2147-756: Is as fatal to the theory of successive development, as if several hundreds had been discovered." In the first edition of Principles , the first volume briefly set out Lyell's concept of a steady state with no real progression of fossils. The sole exception was the advent of humanity, with no great physical distinction from animals, but with absolutely unique intellectual and moral qualities. The second volume dismissed Lamarck's claims of animal forms arising from habits, continuous spontaneous generation of new life, and man having evolved from lower forms. Lyell explicitly rejected Lamarck's concept of transmutation of species, drawing on Cuvier's arguments, and concluded that species had been created with stable attributes. He discussed

2260-493: Is best known, however, for his role in elaborating the doctrine of uniformitarianism . He played a critical role in advancing the study of loess . From 1830 to 1833 his multi-volume Principles of Geology was published. The work's subtitle was "An attempt to explain the former changes of the earth's surface by reference to causes now in operation", and this explains Lyell's impact on science. He drew his explanations from field studies conducted directly before he went to work on

2373-498: Is confined between the two large topographic features, the Chile Rise and the JFR. The northern Chilean margin is poor in sediments due to low sediment supplies from the Andes and the presence of the JFR, which acts as a barrier to the transport of trench sediments from the southern Chile trench to the north. Taitao Peninsula lies near the triple junction and various geological features, such as

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2486-489: Is mainly formed of metasedimentary and metavolcanic rocks of Paleozoic age intruded by Cretaceous and Tertiary, acidic, I-type plutonic rocks of the Patagonian Batholith. In the southern-central Chilean margin, the sediment in the Chile trench is confined to the Chile Rise. The trench is unusually poor in sediments north of the JFR, but is heavily sedimented south of the Chile triple junction. The accretionary prism

2599-663: 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 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

2712-579: Is the first geological epoch of the Neogene Period and extends from about 23.03 to 5.333 million years ago (Ma). The Miocene was named by Scottish geologist Charles Lyell ; the name comes from the Greek words μείων ( meíōn , "less") and καινός ( kainós , "new") and means "less recent" because it has 18% fewer modern marine invertebrates than the Pliocene has. The Miocene followed

2825-452: Is to happen thereafter." Geological remains from the distant past can, and should, be explained by reference to geological processes now in operation and thus directly observable. Lyell's interpretation of geological change as the steady accumulation of minute changes over enormously long spans of time was a powerful influence on the young Charles Darwin . Lyell asked Robert FitzRoy , captain of HMS Beagle , to search for erratic boulders on

2938-627: The British Geological Survey (founded in 1835), and the US Geological Survey (founded in 1879), map and exhibit the natural resources within their countries. Over time, these surveys have been used extensively by modern extractive industries, such as nuclear, coal and oil. Before the work of Lyell, phenomena such as earthquakes were understood by the destruction that they brought. One of the contributions that Lyell made in Principles

3051-535: The Elements in 1838. The book went through six editions, eventually growing to two volumes and ceasing to be the inexpensive, portable handbook that Lyell had originally envisioned. Late in his career, therefore, Lyell produced a condensed version titled Student's Elements of Geology that fulfilled the original purpose. Geological Evidences of the Antiquity of Man brought together Lyell's views on three key themes from

3164-653: The Geological Society of London . The new couple spent their honeymoon in Switzerland and Italy on a geological tour of the area. During the 1840s, Lyell travelled to the United States and Canada, and wrote two popular travel-and-geology books: Travels in North America (1845) and A Second Visit to the United States (1849). In 1866, he was elected a foreign member of the Royal Swedish Academy of Sciences . After

3277-681: The Great Chicago Fire in 1871, Lyell was one of the first to donate books to help found the Chicago Public Library . In 1841, Lyell was elected as a member to the American Philosophical Society . Lyell's wife died in 1873, and two years later (in 1875) Lyell himself died as he was revising the twelfth edition of Principles . He is buried in Westminster Abbey where there is a bust to him by William Theed in

3390-673: The Highlands . His family's second country home was in a completely different geological and ecological area: he spent much of his childhood at Bartley Lodge in the New Forest , in Hampshire in southern England. Lyell entered Exeter College, Oxford , in 1816, and attended William Buckland 's geological lectures. He graduated with a BA Hons. second class degree in classics, in December 1819, and gained his M.A. 1821. After graduation he took up law as

3503-557: The Holocene by French paleontologist Paul Gervais in 1867 – included all deposits from the era subject to human observation. In recent years Lyell's subdivisions have been widely discussed in relation to debates about the Anthropocene . In Principles of Geology (first edition, vol. 3, ch. 2, 1833) Lyell proposed that icebergs could be the means of transport for erratics . During periods of global warming, ice breaks off

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3616-539: 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

3729-522: The Old Red Sandstone of southern Scotland, was named by Louis Agassiz in honour of Lyell. Sir Charles Lyell was buried at Westminster Abbey on 27 February 1875. The pallbearers included T. H. Huxley , the Rev. W. S. Symonds and Mr John Carrick Moore . Lyell had private means, and earned further income as an author. He came from a prosperous family, worked briefly as a lawyer in the 1820s, and held

3842-512: The Oligocene and preceded the Pliocene. As Earth went from the Oligocene through the Miocene and into the Pliocene, the climate slowly cooled towards 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

3955-557: The Taitao ophiolite , are related to the dynamics of the triple junction. Ridge and trench collisions are clear indications of the subduction history around the Pacific Ocean and are likely a dominant mechanism of ophiolite positioning. This results in a rapid sinking and spreading along with magmatic activity near the oceanic trench . Miocene The Miocene ( / ˈ m aɪ . ə s iː n , - oʊ -/ MY -ə-seen, -⁠oh- )

4068-550: 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

4181-689: The survey voyage of the Beagle , and just before it set out FitzRoy gave Darwin Volume 1 of the first edition of Lyell's Principles . When the Beagle made its first stop ashore at St Jago in the Cape Verde islands, Darwin found rock formations which seen "through Lyell's eyes" gave him a revolutionary insight into the geological history of the island, an insight he applied throughout his travels. While in South America Darwin received Volume 2 which considered

4294-399: The 'Recent', is widely cited as providing the foundations for the modern discussion of the Anthropocene . Building on the innovative work of James Hutton and his follower John Playfair , Lyell favoured an indefinitely long age for the earth, despite evidence suggesting an old but finite age. He was a close friend of Charles Darwin , and contributed significantly to Darwin's thinking on

4407-526: The Antarctic plate begun to subduct beneath Patagonia so that the Chile triple junction advanced gradually to its present position in front of Taitao Peninsula at 46°15'. The South American plate is moving away from the Nazca plate and moving in a direction to the north of the Chile ridge spreading center, while the Nazca plate is subducting under the South American plate at a rate of about 80–90 mm/a north of

4520-673: 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,

4633-471: The Chile Rise or Chile Ridge being more prominent in the south. Additionally around 14 Ma, the Chile Rise collided with the South American continental plate . The high relief topography caused the trench to be devoid of sediment at the Chile-South America junction. Subduction accretion is an important process that leads to mountain building and the growth of continents, but it is also associated with

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4746-826: 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

4859-677: 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

4972-526: 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

5085-457: 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

5198-563: 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

5311-694: 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,

5424-567: 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

5537-449: 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 ,

5650-676: 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 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

5763-413: 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

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5876-529: 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,

5989-450: The Origin of Species , Lyell finally offered a tepid endorsement of evolution in the tenth edition of Principles . Elements of Geology began as the fourth volume of the third edition of Principles : Lyell intended the book to act as a suitable field guide for students of geology. The systematic, factual description of geological formations of different ages contained in Principles grew so unwieldy, however, that Lyell split it off as

6102-433: 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

6215-524: The UK and overseas. Highlights include his travels throughout Europe and the United States of America, the drafts of his correspondence with the likes of Charles Darwin, his geological and landscape sketches and his constant gathering of evidence and refinement of his theories. Principles of Geology , Lyell's first book, was also his most famous, most influential, and most important. First published in three volumes in 1830–33, it established Lyell's credentials as an important geological theorist and propounded

6328-423: 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

6441-531: 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 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

6554-469: The ancient spirit of speculation revived, and a desire manifestly shown to cut, rather than patiently untie, the Gordian Knot. -Sir Charles Lyell, Principles of Geology , 1854 edition, p. 196; quoted by Stephen Jay Gould . Lyell saw himself as "the spiritual saviour of geology, freeing the science from the old dispensation of Moses." The two terms, uniformitarianism and catastrophism , were both coined by William Whewell ; in 1866 R. Grove suggested

6667-472: 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

6780-422: 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

6893-422: 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 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

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7006-460: 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

7119-521: The destruction of forearc material. The impact of topographic features, such as topographic features of mountain ranges and faulting, is one important mechanism. An impact between a spreading ridge and a continental forearc can result in a thermal pulse within the forearc. This thermal pulse can be quantified using apatite fission track data and the thermal maturity of organic carbon in the forearc sediment. Several authors have suggested that subduction erosion or slip during earthquakes may be responsible for

7232-522: The doctrine of uniformitarianism . It was a work of synthesis, backed by his own personal observations on his travels. The central argument in Principles was that the present is the key to the past  – a concept of the Scottish Enlightenment which David Hume had stated as "all inferences from experience suppose ... that the future will resemble the past", and James Hutton had described when he wrote in 1788 that "from what has actually been, we have data for concluding with regard to that which

7345-436: 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. Charles Lyell Sir Charles Lyell, 1st Baronet , FRS (14 November 1797 – 22 February 1875)

7458-451: 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

7571-422: 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

7684-429: 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

7797-461: 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

7910-499: 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

8023-653: 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

8136-604: 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

8249-422: The formation of atolls , which supported Lyell's uniformitarianism. On the return of the Beagle (October 1836) Lyell invited Darwin to dinner and from then on they were close friends. Although Darwin discussed evolutionary ideas with him from 1842, Lyell continued to reject evolution in each of the first nine editions of the Principles . He encouraged Darwin to publish, and following the 1859 publication of On

8362-583: The fossil record indicated a directional geohistory in which species went extinct. Around 1826, when he was on circuit, he read Lamarck 's Zoological Philosophy and on 2 March 1827 wrote to Mantell , expressing admiration, but cautioning that he read it "rather as I hear an advocate on the wrong side, to know what can be made of the case in good hands".: He struggled with the implications for human dignity, and later in 1827 wrote private notes on Lamarck's ideas. Lyell reconciled transmutation of species with natural theology by suggesting that it would be as much

8475-598: The founding geology text. He was, along with the earlier John Playfair , the major advocate of James Hutton 's idea of uniformitarianism , that the earth was shaped entirely by slow-moving forces still in operation today, acting over a very long period of time. This was in contrast to catastrophism , an idea of abrupt geological changes, which had been adapted in England to explain landscape features—such as rivers much smaller than their associated valleys—that seemed impossible to explain other than through violent action. Criticizing

8588-588: The geographical distribution of plants and animals, and proposed that every species of plant or animal was descended from a pair or individual, originated in response to differing external conditions. Species would regularly go extinct, in a "struggle for existence" between hybrids, or a "war one with another" due to population pressure. He was vague about how replacement species formed, portraying this as an infrequent occurrence which could rarely be observed. The leading man of science Sir John Herschel wrote from Cape Town on 20 February 1836, thanking Lyell for sending

8701-785: The geology of the Quaternary Period of earth history: glaciers, evolution, and the age of the human race . First published in 1863, it went through three editions that year, with a fourth and final edition appearing in 1873. The book was widely regarded as a disappointment because of Lyell's equivocal treatment of evolution . Lyell, a highly religious man with a strong belief in the special status of human reason, had great difficulty reconciling his beliefs with natural selection . Lyell's geological interests ranged from volcanoes and geological dynamics through stratigraphy , palaeontology , and glaciology to topics that would now be classified as prehistoric archaeology and paleoanthropology . He

8814-460: 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

8927-430: The ideas of Jean-Baptiste Lamarck in some detail. Lyell rejected Lamarck's idea of organic evolution , proposing instead "Centres of Creation" to explain diversity and territory of species. However, as discussed below , many of his letters show he was fairly open to the idea of evolution. In geology Darwin was very much Lyell's disciple, and brought back observations and his own original theorising, including ideas about

9040-449: The intervention of intermediate causes. I left this rather to be inferred, not thinking it worth while to offend a certain class of persons by embodying in words what would only be a speculation." Whewell subsequently questioned this topic, and in March 1837 Lyell told him: As a result of his letters and, no doubt, personal conversations, Huxley and Ernst Haeckel were convinced that, at

9153-587: 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

9266-756: The north aisle. Lyell was knighted ( Kt ) in 1848, and later, in 1864, made a baronet ( Bt ), which is an hereditary honour. He was awarded the Copley Medal of the Royal Society in 1858 and the Wollaston Medal of the Geological Society in 1866. Mount Lyell , the highest peak in Yosemite National Park , is named after him; the crater Lyell on the Moon and a crater on Mars were named in his honour; Mount Lyell in western Tasmania, Australia, located in

9379-543: 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

9492-566: The number and proportion of marine shells encased within. Based on this the third volume of his Principles of Geology , published in 1833, proposed dividing the Tertiary period into four parts, which he named the Eocene , Miocene , Pliocene , and Recent. In 1839, Lyell termed the Pleistocene epoch, distinguishing a more recent fossil layer from the Pliocene. The Recent epoch – renamed

9605-523: 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

9718-408: The poles and floats across submerged continents, carrying debris with it, he conjectured. When the iceberg melts, it rains down sediments upon the land. Because this theory could account for the presence of diluvium, the word drift became the preferred term for the loose, unsorted material, today called till . Furthermore, Lyell believed that the accumulation of fine angular particles covering much of

9831-463: 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

9944-552: The post of Professor of Geology at King's College London in the 1830s. From 1830 onward his books provided both income and fame. Each of his three major books was a work continually in progress. All three went through multiple editions during his lifetime, although many of his friends (such as Darwin) thought the first edition of the Principles was the best written. Lyell used each edition to incorporate additional material, rearrange existing material, and revisit old conclusions in light of new evidence. Throughout his life, Lyell kept

10057-726: The preceding Oligocene and following Pliocene Epochs: Continents continued to drift toward their present positions. Of the modern geologic features, only 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

10170-693: The processes involved in evolution. As Darwin wrote in On the Origin of Species , "He who can read Sir Charles Lyell's grand work on the Principles of Geology, which the future historian will recognise as having produced a revolution in natural science, yet does not admit how incomprehensibly vast have been the past periods of time, may at once close this volume." Lyell helped to arrange the simultaneous publication in 1858 of papers by Darwin and Alfred Russel Wallace on natural selection , despite his personal religious qualms about

10283-453: The reliance of his contemporaries on what he argued were ad hoc explanations, Lyell wrote, Never was there a doctrine more calculated to foster indolence, and to blunt the keen edge of curiosity, than this assumption of the discordance between the former and the existing causes of change... The student was taught to despond from the first. Geology, it was affirmed, could never arise to the rank of an exact science... [With catastrophism] we see

10396-443: The simpler term continuity for Lyell's view, but the old terms persisted. In various revised editions (12 in all, through 1872), Principles of Geology was the most influential geological work in the middle of the 19th century, and did much to put geology on a modern footing. Lyell noted the "economic advantages" that geological surveys could provide, citing their felicity in mineral-rich countries and provinces. Modern surveys, like

10509-647: 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

10622-643: The study of nature. Lyell's grandfather, also Charles Lyell, had made the family fortune supplying the Royal Navy at Montrose , enabling him to buy Kinnordy House. The family seat is located in Strathmore , near the Highland Boundary Fault . Round the house, in the strath , is good farmland, but within a short distance to the north-west, on the other side of the fault, are the Grampian Mountains in

10735-419: The theory of gradual "backed up-building" of volcanoes . In stratigraphy his division of the Tertiary period into the Pliocene , Miocene , and Eocene was highly influential. He incorrectly conjectured that icebergs were the impetus behind the transport of glacial erratics , and that silty loess deposits might have settled out of flood waters. His creation of a separate period for human history, entitled

10848-658: The theory of natural selection by Darwin and Alfred Russel Wallace in 1858: each had arrived at the theory independently. Lyell's views on gradual change and the power of a long time scale were important because Darwin thought that populations of an organism changed very slowly. Although Lyell rejected evolution at the time of writing the Principles , after the Darwin–Wallace papers and the Origin Lyell wrote in one of his notebooks on 3 May 1860: Lyell's acceptance of natural selection, Darwin's proposed mechanism for evolution,

10961-433: The theory. He later published evidence from geology of the time man had existed on the earth. Lyell was born into a wealthy family, on 14 November 1797, at the family's estate house , Kinnordy House , near Kirriemuir in Forfarshire. He was the eldest of ten children. Lyell's father, also named Charles Lyell , was noted as a translator and scholar of Dante . An accomplished botanist, it was he who first exposed his son to

11074-521: The time he wrote Principles , he believed new species had arisen by natural methods. Adam Sedgwick wrote worried letters to him about this. By the time Darwin returned from the Beagle survey expedition in 1836, he had begun to doubt Lyell's ideas about the permanence of species. He continued to be a close personal friend, and Lyell was one of the first scientists to support On the Origin of Species , though he did not subscribe to all its contents. Lyell

11187-604: The triple junction. The triple junction of the Chile Ridge, the Chile Trench and the Antarctic plate collided about 14 Ma ago near the latitude of Tierra del Fuego . Since then it has migrated north, with the actual triple junction now located at 46°12'S.The Chilean margin consists of the Nazca-Antarctic spreading center, the Chile Rise or Chile Ridge, and the Chile Ridge, with the Nazca-Antarctic spreading center being at 46.5° S,

11300-446: The upheaval argument supported by other geologists. Lyell was a key figure in establishing the classification of more recent geological deposits, long known as the Tertiary period. From May 1828, until February 1829, he travelled with Roderick Impey Murchison (1792–1871) to the south of France (Auvergne volcanic district) and to Italy. In these areas he concluded that the recent strata (rock layers) could be categorised according to

11413-465: The uplift of the Coastal Cordillera, a trench-parallel morphostructural system in north Chile. The Juan Fernández Ridge (JFR) is a prominent feature on the oceanic Nazca lithosphere located west of the Chile Trench. The O'Higgins seamount group, surrounded by a topographic swell, acts as a barrier between the north and south half of the Chile Trench. The continental basement of southern Chile

11526-650: 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

11639-401: The world (today called loess ) was a deposit settled from mountain flood water. Today some of Lyell's mechanisms for geological processes have been disproven, though many have stood the test of time. His observational methods and general analytical framework remain in use today as foundational principles in geology. Lyell initially accepted the conventional view of other men of science, that

11752-423: 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

11865-578: Was a Scottish geologist who demonstrated the power of known natural causes in explaining the earth's history. He is best known today for his association with Charles Darwin and as the author of Principles of Geology (1830–33), which presented to a wide public audience the idea that the earth was shaped by the same natural processes still in operation today, operating at similar intensities. The philosopher William Whewell dubbed this gradualistic view " uniformitarianism " and contrasted it with catastrophism , which had been championed by Georges Cuvier and

11978-610: 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

12091-399: Was also a friend of Darwin's closest colleagues, Joseph Dalton Hooker and Huxley , but unlike them he struggled to square his religious beliefs with evolution. This inner struggle has been much commented on. He had particular difficulty in believing in natural selection as the main motive force in evolution. Lyell and Hooker were instrumental in arranging the peaceful co-publication of

12204-405: 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

12317-498: Was better accepted in Europe. The combination of evidence and eloquence in Principles convinced a wide range of readers of the significance of " deep time " for understanding the earth and environment. Lyell's scientific contributions included a pioneering explanation of climate change, in which shifting boundaries between oceans and continents could be used to explain long-term variations in temperature and rainfall. Lyell also gave influential explanations of earthquakes and developed

12430-571: Was equivocal, and came in the tenth edition of Principles . The Antiquity of Man (published in early February 1863, just before Huxley's Man's place in nature ) drew these comments from Darwin to Huxley: "I am fearfully disappointed at Lyell's excessive caution" and "The book is a mere 'digest'". Quite strong remarks: no doubt Darwin resented Lyell's repeated suggestion that he owed a lot to Lamarck , whom he (Darwin) had always specifically rejected. Darwin's daughter Henrietta (Etty) wrote to her father: "Is it fair that Lyell always calls your theory

12543-623: 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

12656-627: 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

12769-421: Was to explain the cause of earthquakes. Lyell, in contrast focused on recent earthquakes (150 yrs), evidenced by surface irregularities such as faults, fissures, stratigraphic displacements and depressions. Lyell's work on volcanoes focused largely on Vesuvius and Etna , both of which he had earlier studied. His conclusions supported gradual building of volcanoes, so-called "backed up-building", as opposed to

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