Journal articles: 'Pleistocene extinctions'

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MORLAN, R. E. "Pleistocene Extinction Reexamined: Quaternary Extinctions." Science 228, no. 4701 (May 17, 1985): 870–71. http://dx.doi.org/10.1126/science.228.4701.870.

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Pires, Mathias M., Paul L. Koch, Richard A. Fariña, Marcus A. M. de Aguiar, Sérgio F. dos Reis, and Paulo R. Guimarães. "Pleistocene megafaunal interaction networks became more vulnerable after human arrival." Proceedings of the Royal Society B: Biological Sciences 282, no. 1814 (September 7, 2015): 20151367. http://dx.doi.org/10.1098/rspb.2015.1367.

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The end of the Pleistocene was marked by the extinction of almost all large land mammals worldwide except in Africa. Although the debate on Pleistocene extinctions has focused on the roles of climate change and humans, the impact of perturbations depends on properties of ecological communities, such as species composition and the organization of ecological interactions. Here, we combined palaeoecological and ecological data, food-web models and community stability analysis to investigate if differences between Pleistocene and modern mammalian assemblages help us understand why the megafauna died out in the Americas while persisting in Africa. We show Pleistocene and modern assemblages share similar network topology, but differences in richness and body size distributions made Pleistocene communities significantly more vulnerable to the effects of human arrival. The structural changes promoted by humans in Pleistocene networks would have increased the likelihood of unstable dynamics, which may favour extinction cascades in communities facing extrinsic perturbations. Our findings suggest that the basic aspects of the organization of ecological communities may have played an important role in major extinction events in the past. Knowledge of community-level properties and their consequences to dynamics may be critical to understand past and future extinctions.

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Faith, J. Tyler, and James F. O'Connell. "Revisiting the late Pleistocene mammal extinction record at Tight Entrance Cave, southwestern Australia." Quaternary Research 76, no. 3 (November 2011): 397–400. http://dx.doi.org/10.1016/j.yqres.2011.08.001.

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AbstractTight Entrance Cave (TEC) in southwestern Australia provides a Pleistocene sequence documenting the extinction of 14 large mammal species. This record has been interpreted as indicating that extinctions did not occur during or before the penultimate glacial maximum (PGM) and that humans played a primary role in the extinctions. However, it remains possible that the majority of extinct megafauna persisted no later than the PGM. The TEC extinctions correspond with vegetation change, a cooling/drying trend, increased biomass burning, and increasingly unstable small mammal communities. The initiation of these trends predates human arrival on the continent and implies environmentally mediated extinctions.

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Louys, Julien, Todd J. Braje, Chun-Hsiang Chang, Richard Cosgrove, Scott M. Fitzpatrick, Masaki Fujita, Stuart Hawkins, et al. "No evidence for widespread island extinctions after Pleistocene hominin arrival." Proceedings of the National Academy of Sciences 118, no. 20 (May 3, 2021): e2023005118. http://dx.doi.org/10.1073/pnas.2023005118.

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The arrival of modern humans into previously unoccupied island ecosystems is closely linked to widespread extinction, and a key reason cited for Pleistocene megafauna extinction is anthropogenic overhunting. A common assumption based on late Holocene records is that humans always negatively impact insular biotas, which requires an extrapolation of recent human behavior and technology into the archaeological past. Hominins have been on islands since at least the early Pleistocene and Homo sapiens for at least 50 thousand y (ka). Over such lengthy intervals it is scarcely surprising that significant evolutionary, behavioral, and cultural changes occurred. However, the deep-time link between human arrival and island extinctions has never been explored globally. Here, we examine archaeological and paleontological records of all Pleistocene islands with a documented hominin presence to examine whether humans have always been destructive agents. We show that extinctions at a global level cannot be associated with Pleistocene hominin arrival based on current data and are difficult to disentangle from records of environmental change. It is not until the Holocene that large-scale changes in technology, dispersal, demography, and human behavior visibly affect island ecosystems. The extinction acceleration we are currently experiencing is thus not inherent but rather part of a more recent cultural complex.

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Beck, Michael W. "On discerning the cause of late Pleistocene megafaunal extinctions." Paleobiology 22, no. 1 (1996): 91–103. http://dx.doi.org/10.1017/s0094837300016043.

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I examine the late Pleistocene megafaunal extinctions by testing the only extinction model with strong a priori predictions, the blitzkrieg model (Martin 1973; Mosimann and Martin 1975). I first test an assumption of the blitzkrieg and other extinction models that the megafaunal extinctions occurred in the terminal Wisconsin (12-10 Ka). This assumption has been disputed by Grayson (1989, 1991), but I find that both a reanalysis of Grayson's data and an analysis of new reliable data support a terminal Wisconsin extinction.The blitzkrieg model predicts that the ranges of megafauna in North America were constricted as the semicircular front of hunters moved southeastward; hence the extinctions should be time-transgressive from northwest to southeast. I test this prediction in three separate analyses that examine (1) the location of terminal sites for each taxon relative to all their other late Wisconsin fossil sites, (2) the location of terminal sites for each taxon relative to all their other reliably dated late Wisconsin fossil sites, and (3) the spatio-temporal pattern of all the reliably dated terminal Wisconsin sites without regard to taxonomy. The geographic distribution of the megafaunal remains does not support the blitzkrieg hypothesis in any of the three analyses. Moreover, all of the patterns in the data are in a direction opposite to that predicted by the blitzkrieg hypothesis. I examine how these conclusions affect both climatic and predation models, particularly in relation to the testability of other extinction hypotheses.

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Grayson, Donald K. "Deciphering North American Pleistocene Extinctions." Journal of Anthropological Research 63, no. 2 (July 2007): 185–213. http://dx.doi.org/10.3998/jar.0521004.0063.205.

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Hofreiter, Michael. "Pleistocene Extinctions: Haunting the Survivors." Current Biology 17, no. 15 (August 2007): R609—R611. http://dx.doi.org/10.1016/j.cub.2007.06.031.

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Budd, Ann F., Thomas A. Stemann, and Kenneth G. Johnson. "Late Cenozoic turnover in the Caribbean reef coral fauna." Paleontological Society Special Publications 6 (1992): 43. http://dx.doi.org/10.1017/s2475262200006031.

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Study of the stratigraphic ranges of reef coral species in scattered sequences (Dominican Republic, Bahamas, Costa Rica, Jamaica, and Florida) suggests that a major episode of faunal turnover occurred in the Caribbean region between early Pliocene and mid Pleistocene time. In a data set composed of all reef corals except the families Mussidae and Oculinidae and the genera Cladocora and Madracis, approximately 90% of the Mio-Pliocene fauna, composed of as many as 65–70 species, became extinct during this time interval. Ten of 27 genera became extinct. Despite the high numbers of extinctions, the total number of species in the Caribbean reef coral fauna dropped only slightly over the time interval, due to similar numbers of originations and extinctions in the fauna. With one possible exception, new species arose in surviving genera, and no new genera formed.Although similar numbers of species became extinct within early Pliocene, late Pliocene, and early Pleistocene time units, shallow water communities experienced higher numbers of extinctions during the late Miocene and early Pliocene. Deeper water communities experienced higher numbers of extinctions during the late Pliocene and early Pleistocene. Species surviving the turnover episode occur in deeper water communities and belong predominantly to the family Agariciidae. Nearshore grass flat communities contain the highest number of early extinctions. No difference in extinction patterns could be detected between taxa which reproduce primarily by fragmentation and those that reproduce primarily by larval recruitment. Although originations appear evenly distributed among community types, a large number occur in Florida along the northern margin of faunal distribution.The increased extinctions in shallow water communities and increased originations in the north suggest that turnover occurred primarily in response to change in abiotic factors such as temperature and siltation, and not in response to species-area effects associated with sea level change.

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Andermann, Tobias, Søren Faurby, Samuel T. Turvey, Alexandre Antonelli, and Daniele Silvestro. "The past and future human impact on mammalian diversity." Science Advances 6, no. 36 (September 2020): eabb2313. http://dx.doi.org/10.1126/sciadv.abb2313.

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To understand the current biodiversity crisis, it is crucial to determine how humans have affected biodiversity in the past. However, the extent of human involvement in species extinctions from the Late Pleistocene onward remains contentious. Here, we apply Bayesian models to the fossil record to estimate how mammalian extinction rates have changed over the past 126,000 years, inferring specific times of rate increases. We specifically test the hypothesis of human-caused extinctions by using posterior predictive methods. We find that human population size is able to predict past extinctions with 96% accuracy. Predictors based on past climate, in contrast, perform no better than expected by chance, suggesting that climate had a negligible impact on global mammal extinctions. Based on current trends, we predict for the near future a rate escalation of unprecedented magnitude. Our results provide a comprehensive assessment of the human impact on past and predicted future extinctions of mammals.

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Russell, Sharman Apt. "The Pleistocene Extinctions: A Bedtime Story." Missouri Review 18, no. 2 (1995): 30–39. http://dx.doi.org/10.1353/mis.1995.0025.

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Kooyman, Brian, L. V. Hills, Shayne Tolman, and Paul McNeil. "Late Pleistocene Western Camel (Camelops Hesternus) Hunting in Southwestern Canada." American Antiquity 77, no. 1 (January 2012): 115–24. http://dx.doi.org/10.7183/0002-7316.77.1.115.

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AbstractLate Pleistocene large mammal extinctions in North America have been attributed to a number of factors or combination of factors, primarily climate change and human hunting, but the relative roles of these factors remain much debated. Clo-vis-period hunters exploited species such as mammoth, but many now extinct species such as camels were seemingly not hunted. Archaeological evidence from the Wally’s Beach site in southern Canada, including stone tools and butchered bone, provide the first evidence that Clovis people hunted North American camels. Archaeologists generally dismiss human hunting as a significant contributor to Pleistocene extinctions in North America, but Wally’s Beach demonstrates that human hunting was more inclusive than assumed and we must continue to consider hunting as a factor in Pleistocene extinctions.

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Davis, Owen K. "Spores of the Dung Fungus Sporormiella: Increased Abundance in Historic Sediments and Before Pleistocene Megafaunal Extinction." Quaternary Research 28, no. 2 (September 1987): 290–94. http://dx.doi.org/10.1016/0033-5894(87)90067-6.

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AbstractSpores of the dung fungus Sporormiella become abundant following the historic introduction of grazing herbivores at seven sites in the western United States. During the Holocene they are generally rare, but at six sites Sporormiella spores are abundant before the extinction of Pleistocene megaherbivores ca. 11,000 yr B.P. Sporormiella spores are directly linked to extinct megaherbivores by their presence in mammoth dung preserved in Bechan Cave, Southern Utah. Their abundance in late-glacial sediments may reflect the abundance of megaherbivores during Quaternary, thereby indicating the age of Pleistocene extinctions where other indicators are absent.

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Meltzer, David J. "Overkill, glacial history, and the extinction of North America’s Ice Age megafauna." Proceedings of the National Academy of Sciences 117, no. 46 (November 9, 2020): 28555–63. http://dx.doi.org/10.1073/pnas.2015032117.

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The end of the Pleistocene in North America saw the extinction of 38 genera of mostly large mammals. As their disappearance seemingly coincided with the arrival of people in the Americas, their extinction is often attributed to human overkill, notwithstanding a dearth of archaeological evidence of human predation. Moreover, this period saw the extinction of other species, along with significant changes in many surviving taxa, suggesting a broader cause, notably, the ecological upheaval that occurred as Earth shifted from a glacial to an interglacial climate. But, overkill advocates ask, if extinctions were due to climate changes, why did these large mammals survive previous glacial−interglacial transitions, only to vanish at the one when human hunters were present? This question rests on two assumptions: that previous glacial−interglacial transitions were similar to the end of the Pleistocene, and that the large mammal genera survived unchanged over multiple such cycles. Neither is demonstrably correct. Resolving the cause of large mammal extinctions requires greater knowledge of individual species’ histories and their adaptive tolerances, a fuller understanding of how past climatic and ecological changes impacted those animals and their biotic communities, and what changes occurred at the Pleistocene−Holocene boundary that might have led to those genera going extinct at that time. Then we will be able to ascertain whether the sole ecologically significant difference between previous glacial−interglacial transitions and the very last one was a human presence.

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Estes, James A., Alexander Burdin, and Daniel F. Doak. "Sea otters, kelp forests, and the extinction of Steller’s sea cow." Proceedings of the National Academy of Sciences 113, no. 4 (October 26, 2015): 880–85. http://dx.doi.org/10.1073/pnas.1502552112.

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The late Pleistocene extinction of so many large-bodied vertebrates has been variously attributed to two general causes: rapid climate change and the effects of humans as they spread from the Old World to previously uninhabited continents and islands. Many large-bodied vertebrates, especially large apex predators, maintain their associated ecosystems through top-down forcing processes, especially trophic cascades, and megaherbivores also exert an array of strong indirect effects on their communities. Thus, a third possibility for at least some of the Pleistocene extinctions is that they occurred through habitat changes resulting from the loss of these other keystone species. Here we explore the plausibility of this mechanism, using information on sea otters, kelp forests, and the recent extinction of Steller's sea cows from the Commander Islands. Large numbers of sea cows occurred in the Commander Islands at the time of their discovery by Europeans in 1741. Although extinction of these last remaining sea cows during early years of the Pacific maritime fur trade is widely thought to be a consequence of direct human overkill, we show that it is also a probable consequence of the loss of sea otters and the co-occurring loss of kelp, even if not a single sea cow had been killed directly by humans. This example supports the hypothesis that the directly caused extinctions of a few large vertebrates in the late Pleistocene may have resulted in the coextinction of numerous other species.

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Wan, Xinru, and Zhibin Zhang. "Climate warming and humans played different roles in triggering Late Quaternary extinctions in east and west Eurasia." Proceedings of the Royal Society B: Biological Sciences 284, no. 1851 (March 22, 2017): 20162438. http://dx.doi.org/10.1098/rspb.2016.2438.

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Climate change and humans are proposed as the two key drivers of total extinction of many large mammals in the Late Pleistocene and Early Holocene, but disentangling their relative roles remains challenging owing to a lack of quantitative evaluation of human impact and climate-driven distribution changes on the extinctions of these large mammals in a continuous temporal–spatial dimension. Here, our analyses showed that temperature change had significant effects on mammoth (genus Mammuthus ), rhinoceros (Rhinocerotidae), horse (Equidae) and deer (Cervidae). Rapid global warming was the predominant factor driving the total extinction of mammoths and rhinos in frigid zones from the Late Pleistocene and Early Holocene. Humans showed significant, negative effects on extirpations of the four mammalian taxa, and were the predominant factor causing the extinction or major extirpations of rhinos and horses. Deer survived both rapid climate warming and extensive human impacts. Our study indicates that both the current rates of warming and range shifts of species are much faster than those from the Late Pleistocene to Holocene. Our results provide new insight into the extinction of Late Quaternary megafauna by demonstrating taxon-, period- and region-specific differences in extinction drivers of climate change and human disturbances, and some implications about the extinction risk of animals by recent and ongoing climate warming.

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Woodman, Neal, and Nancy Beavan Athfield. "Post-Clovis survival of American Mastodon in the southern Great Lakes Region of North America." Quaternary Research 72, no. 3 (November 2009): 359–63. http://dx.doi.org/10.1016/j.yqres.2009.06.009.

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AbstractThe end of the Pleistocene in North America was marked by a wave of extinctions of large mammals, with the last known appearances of many species falling between ca. 11,000–10,000 14C yr BP. Temporally, this period overlaps with the Clovis Paleoindian cultural complex (11,190–10,530 14C yr BP) and with sudden climatic changes that define the beginning of the Younger Dryas chronozone (ca. 11,000–10,000 14C yr BP), both of which have been considered as potential proximal causes of this extinction event. Radiocarbon dating of enamel and filtered bone collagen from an extinct American Mastodon (Mammut americanum) from northern Indiana, USA, by accelerator mass spectrometer yielded direct dates of 10,055 ± 40 14C yr BP and 10,032 ± 40 14C yr BP, indicating that the animal survived beyond the Clovis time period and into the late Younger Dryas. Although the late survival of this species in mid-continental North America does not remove either humans or climatic change as contributing causes for the late Pleistocene extinctions, neither Clovis hunters nor the climatic perturbations initiating the Younger Dryas chronozone were immediately responsible for driving mastodons to extinction.

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Marshall, Charles R., Emily L. Lindsey, Natalia A. Villavicencio, and Anthony D. Barnosky. "A Quantitative Model for Distinguishing Between Climate Change, Human Impact, and Their Synergistic Interaction as Drivers of the Late Quaternary Megafaunal Extinctions." Paleontological Society Papers 21 (October 2015): 1–20. http://dx.doi.org/10.1017/s1089332600002941.

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A simple quantitative approach is presented for determining the relative importance of climate change and human impact in driving late Quaternary megafaunal extinctions. This method is designed to determine whether climate change or human impact alone can account for these extinctions, or whether both were important, acting independently (additively) and/or synergistically (multiplicatively). This approach is applied to the megafaunal extinction in the Última Esperanza region of southern Chile. In this region, there is a complex pattern of extinction. Records of environmental change include temperature proxies and pollen records that capture the transition from cold grasslands to warmer, moister forests, as well as evidence of initial human arrival. Uncertainty in extinction times and time of human arrival complicates the analysis, as does uncertainty about the size of local human populations, and the nature, strength, and persistence of their impacts through the late Pleistocene and early Holocene. Results of the Ultima Esperanza analysis were equivocal, with evidence for climate- and human-driven extinction, with each operating alone or additively. The results depend on the exact timing of extinctions and human arrival, and assumptions about the kinds of pressures humans put on the megafauna. There was little evidence for positive synergistic effects, while the unexpected possibility of negative synergistic interactions arose in some scenarios. Application of this quantitative approach highlights the need for higher precision dating of the extinctions and human arrival, and provides a platform for sharpening our understanding of these megafaunal extinctions.

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Metcalf, Jessica L., Chris Turney, Ross Barnett, Fabiana Martin, Sarah C. Bray, Julia T. Vilstrup, Ludovic Orlando, et al. "Synergistic roles of climate warming and human occupation in Patagonian megafaunal extinctions during the Last Deglaciation." Science Advances 2, no. 6 (June 2016): e1501682. http://dx.doi.org/10.1126/sciadv.1501682.

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The causes of Late Pleistocene megafaunal extinctions (60,000 to 11,650 years ago, hereafter 60 to 11.65 ka) remain contentious, with major phases coinciding with both human arrival and climate change around the world. The Americas provide a unique opportunity to disentangle these factors as human colonization took place over a narrow time frame (~15 to 14.6 ka) but during contrasting temperature trends across each continent. Unfortunately, limited data sets in South America have so far precluded detailed comparison. We analyze genetic and radiocarbon data from 89 and 71 Patagonian megafaunal bones, respectively, more than doubling the high-quality Pleistocene megafaunal radiocarbon data sets from the region. We identify a narrow megafaunal extinction phase 12,280 ± 110 years ago, some 1 to 3 thousand years after initial human presence in the area. Although humans arrived immediately prior to a cold phase, the Antarctic Cold Reversal stadial, megafaunal extinctions did not occur until the stadial finished and the subsequent warming phase commenced some 1 to 3 thousand years later. The increased resolution provided by the Patagonian material reveals that the sequence of climate and extinction events in North and South America were temporally inverted, but in both cases, megafaunal extinctions did not occur until human presence and climate warming coincided. Overall, metapopulation processes involving subpopulation connectivity on a continental scale appear to have been critical for megafaunal species survival of both climate change and human impacts.

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Ceballos, Gerardo, Joaquín Arroyo-Cabrales, and Eduardo Ponce. "Effects of Pleistocene environmental changes on the distribution and community structure of the mammalian fauna of Mexico." Quaternary Research 73, no. 3 (May 2010): 464–73. http://dx.doi.org/10.1016/j.yqres.2010.02.006.

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Biological communities in Mexico experienced profound changes in species composition and structure as a consequence of the environmental fluctuations during the Pleistocene. Based on the recent and fossil Mexican mammal checklists, we determine the distribution, composition, diversity, and community structure of late Pleistocene mammalian faunas, and analyze extinction patterns and response of individual species to environmental changes. We conclude that (1) differential extinctions occurred at family, genus, and species level, with a major impact on species heavier than 100 kg, including the extinction all proboscideans and several ruminants; (2) Pleistocene mammal communities in Mexico were more diverse than recent ones; and (3) the current assemblages of species are relatively young. Furthermore, Pleistocene relicts support the presence of biogeographic corridors; important refugia existed as well as centers of speciation in isolated regions. We identified seven corridors: eastern USA–Sierra Madre Oriental corridor, Rocky Mountains–Sierra Madre Occidental corridor, Central United States–Northern Mexico corridor, Transvolcanic Belt–Sierra Madre del Sur corridor, western USA–Baja California corridor, Tamaulipas–Central America gulf lowlands corridor, and Sonora–Central America Pacific lowlands corridor. Our study suggests that present mammalian assemblages are very different than the ones in the late Pleistocene.

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Brault, M. O., L. A. Mysak, H. D. Matthews, and C. T. Simmons. "Assessing the impact of late Pleistocene megafaunal extinctions on global vegetation and climate." Climate of the Past 9, no. 4 (August 2, 2013): 1761–71. http://dx.doi.org/10.5194/cp-9-1761-2013.

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Abstract. The end of the Pleistocene was a turning point for the Earth system as climate gradually emerged from millennia of severe glaciation in the Northern Hemisphere. The deglacial climate change coincided with an unprecedented decline in many species of Pleistocene megafauna, including the near-total eradication of the woolly mammoth. Due to an herbivorous diet that presumably involved large-scale tree grazing, the mammoth extinction has been associated with the rapid expansion of dwarf deciduous trees in Siberia and Beringia, thus potentially contributing to the changing climate of the period. In this study, we use the University of Victoria Earth System Climate Model (UVic ESCM) to simulate the possible effects of these extinctions on climate during the latest deglacial period. We have explored various hypothetical scenarios of forest expansion in the northern high latitudes, quantifying the biogeophysical effects in terms of changes in surface albedo and air temperature. These scenarios include a Maximum Impact Scenario (MIS) which simulates the greatest possible post-extinction reforestation in the model, and sensitivity tests which investigate the timing of extinction, the fraction of trees grazed by mammoths, and the southern extent of mammoth habitats. We also show the results of a simulation with free atmospheric CO2-carbon cycle interactions. For the MIS, we obtained a surface albedo increase and global warming of 0.006 and 0.175 °C, respectively. Less extreme scenarios produced smaller global mean temperature changes, though local warming in some locations exceeded 0.3 °C even in the more realistic extinction scenarios. In the free CO2 simulation, the biogeophysical-induced warming was amplified by a biogeochemical effect, whereby the replacement of high-latitude tundra with shrub forest led to a release of soil carbon to the atmosphere and a small atmospheric CO2 increase. Overall, our results suggest the potential for a small, though non-trivial, effect of megafaunal extinctions on Pleistocene climate.

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Jordan, GI, and RS Hill. "Two new Banksia species from pleistocene sediments in western Tasmania." Australian Systematic Botany 4, no. 3 (1991): 499. http://dx.doi.org/10.1071/sb9910499.

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Subtribe Banksiinae of the Proteaceae was diverse in Tasmania in the early and middle Tertiary, but is now restricted to two species, Banksia marginata and B. serrata. Rapid and extreme environmental changes during the Pleistocene are likely causes of the extinction of some Banksia species in Tasmania. Such extinctions may have been common in many taxonomic groups. The leaves and infructescences of Banksia kingii Jordan & Hill, sp. nov. are described from late Pleistocene sediments. This is the most recent macrofossil record of a now extinct species in Tasmania. Banksia kingii is related to the extant B. saxicola. Banksia strahanensis Jordan & Hill, sp. nov. (known only from a leaf and leaf fragments and related to B. spinulosa) is described from Early to Middle Pleistocene sediments in Tasmania. This represents the third Pleistocene macrofossil record of a plant species which is now extinct in Tasmania.

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Owen-Smith, Norman. "Pleistocene extinctions: the pivotal role of megaherbivores." Paleobiology 13, no. 3 (1987): 351–62. http://dx.doi.org/10.1017/s0094837300008927.

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Two alternative hypotheses have been advanced to explain the demise of about half of the mammalian genera exceeding 5 kg in body mass in the later Pleistocene. One hypothesis invokes climatic change and resulting habitat transformations. This fails to predict the increased likelihood of extinctions with increasing body size, greater severity in both North and South America than in Eurasia or Australia, lack of simultaneous extinctions in Africa and tropical Asia, and the absence of extinctions at the end of previous glacial periods. The other hypothesis invokes human predation as the primary cause. This fails to explain the simultaneous extinctions of a number of mammalian and avian species not obviously vulnerable to human overkill. I propose a “keystone herbivore” hypothesis, based on the ecology of extant African species of megaherbivore, (i.e., animals exceeding 1,000 kg in body mass). Due to their invulnerability to non-human predation on adults, these species attain saturation densities at which they may radically transform vegetation structure and composition. African elephant can change closed woodland or thicket into open grassy savanna, and create open gaps colonized by rapidly-regenerating trees in forests. Grazing white rhinoceros and hippopotamus transform tall grasslands into lawns of more nutritious short grasses. The elimination of megaherbivores elsewhere in the world by human hunters at the end of the Pleistocene would have promoted reverse changes in vegetation. The conversion of the open parklike woodlands and mosaic grasslands typical of much of North America during the Pleistocene to the more uniform forests and prairie grasslands we find today could be a consequence. Such habitat changes would have been detrimental to the distribution and abundance of smaller herbivores dependent upon the nutrient-rich and spatially diverse vegetation created by megaherbivore impact. At the same time these species would have become more vulnerable to human predation. The elimination of megaherbivore influence is the major factor differentiating habitat changes at the end of the terminal Pleistocene glaciation from those occurring at previous glacial-interglacial transitions.

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Meltzer, David J. "Pleistocene Overkill and North American Mammalian Extinctions." Annual Review of Anthropology 44, no. 1 (October 21, 2015): 33–53. http://dx.doi.org/10.1146/annurev-anthro-102214-013854.

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MARKGRAF, V. "Late Pleistocene Faunal Extinctions in Southern Patagonia." Science 228, no. 4703 (May 31, 1985): 1110–12. http://dx.doi.org/10.1126/science.228.4703.1110.

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Lundgren, Erick J., Daniel Ramp, John Rowan, Owen Middleton, Simon D. Schowanek, Oscar Sanisidro, Scott P. Carroll, et al. "Introduced herbivores restore Late Pleistocene ecological functions." Proceedings of the National Academy of Sciences 117, no. 14 (March 23, 2020): 7871–78. http://dx.doi.org/10.1073/pnas.1915769117.

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Large-bodied mammalian herbivores dominated Earth’s terrestrial ecosystems for several million years before undergoing substantial extinctions and declines during the Late Pleistocene (LP) due to prehistoric human impacts. The decline of large herbivores led to widespread ecological changes due to the loss of their ecological functions, as driven by their unique combinations of traits. However, recently, humans have significantly increased herbivore species richness through introductions in many parts of the world, potentially counteracting LP losses. Here, we assessed the extent to which introduced herbivore species restore lost—or contribute novel—functions relative to preextinction LP assemblages. We constructed multidimensional trait spaces using a trait database for all extant and extinct mammalian herbivores ≥10 kg known from the earliest LP (∼130,000 ybp) to the present day. Extinction-driven contractions of LP trait space have been offset through introductions by ∼39% globally. Analysis of trait space overlap reveals that assemblages with introduced species are overall more similar to those of the LP than native-only assemblages. This is because 64% of introduced species are more similar to extinct rather than extant species within their respective continents. Many introduced herbivores restore trait combinations that have the capacity to influence ecosystem processes, such as wildfire and shrub expansion in drylands. Although introduced species have long been a source of contention, our findings indicate that they may, in part, restore ecological functions reflective of the past several million years before widespread human-driven extinctions.

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Tóth, Anikó B., S. Kathleen Lyons, W. Andrew Barr, Anna K. Behrensmeyer, Jessica L. Blois, René Bobe, Matt Davis, et al. "Reorganization of surviving mammal communities after the end-Pleistocene megafaunal extinction." Science 365, no. 6459 (September 19, 2019): 1305–8. http://dx.doi.org/10.1126/science.aaw1605.

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Large mammals are at high risk of extinction globally. To understand the consequences of their demise for community assembly, we tracked community structure through the end-Pleistocene megafaunal extinction in North America. We decomposed the effects of biotic and abiotic factors by analyzing co-occurrence within the mutual ranges of species pairs. Although shifting climate drove an increase in niche overlap, co-occurrence decreased, signaling shifts in biotic interactions. Furthermore, the effect of abiotic factors on co-occurrence remained constant over time while the effect of biotic factors decreased. Biotic factors apparently played a key role in continental-scale community assembly before the extinctions. Specifically, large mammals likely promoted co-occurrence in the Pleistocene, and their loss contributed to the modern assembly pattern in which co-occurrence frequently falls below random expectations.

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Brault, M. O., L. A. Mysak, H. D. Matthews, and C. T. Simmons. "Assessing the impact of late Pleistocene megafaunal extinctions on global vegetation and climate." Climate of the Past Discussions 9, no. 1 (January 21, 2013): 435–65. http://dx.doi.org/10.5194/cpd-9-435-2013.

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Abstract. The end of the Pleistocene marked a turning point for the Earth system as climate gradually emerged from millennia of severe glaciation in the Northern Hemisphere. It is widely acknowledged that the deglacial climate change coincided with an unprecedented decline in many species of large terrestrial mammals, including the near-total eradication of the woolly mammoth. Due to an herbivorous diet that presumably involved large-scale tree grazing, the mammoth expansion would have accelerated the expansion of dwarf deciduous trees in Siberia and Beringia, thus contributing to the changing climate of the period. In this study, we use the University of Victoria Earth System Climate Model (UVic ESCM) to simulate the possible effects of megafaunal extinctions on Pleistocene climate change. We have explored various hypothetical scenarios of forest expansion in the Northern Continents, quantifying the regional and global biogeophysical effects in terms of changes in surface albedo and air temperature. In particular, we focus our attention on a Maximum Impact Scenario (MIS) which simulates the greatest possible post-extinction reforestation in the model. More realistic experiments include sensitivity tests based on the timing of extinction, the fraction of trees grazed by mammoths, and the size of mammoth habitats. We also show the results of a simulation with free (non-prescribed) atmospheric CO2. For the MIS, we obtained a surface albedo increase of 0.006, which resulted in a global warming of 0.175 °C. Less extreme scenarios produced smaller global mean temperature changes, though local warming in some locations exceeded 0.3 °C even in the more realistic extinction scenarios. In the free CO2 simulation, the biogeophysical-induced warming was amplified by a biogeochemical effect whereby the replacement of high-latitude tundra with shrub forest led to a release of soil carbon to the atmosphere and a small atmospheric CO2 increase. Overall, our results suggest the potential for a small, though non-trivial, effect of megafaunal extinctions on Pleistocene climate change.

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Emery-Wetherell, Meaghan M., Brianna K. McHorse, and Edward Byrd Davis. "Spatially explicit analysis sheds new light on the Pleistocene megafaunal extinction in North America." Paleobiology 43, no. 4 (August 29, 2017): 642–55. http://dx.doi.org/10.1017/pab.2017.15.

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AbstractThe late Pleistocene megafaunal extinctions may have been the first extinctions directly related to human activity, but in North America the close temporal proximity of human arrival and the Younger Dryas climate event has hindered efforts to identify the ultimate extinction cause. Previous work evaluating the roles of climate change and human activity in the North American megafaunal extinction has been stymied by a reliance on geographic binning, yielding contradictory results among researchers. We used a fine-scale geospatial approach in combination with 95 megafaunal last-appearance and 75 human first-appearance radiocarbon dates to evaluate the North American megafaunal extinction. We used kriging to create interpolated first- and last-appearance surfaces from calibrated radiocarbon dates in combination with their geographic autocorrelation. We found substantial evidence for overlap between megafaunal and human populations in many but not all areas, in some cases exceeding 3000 years of predicted overlap. We also found that overlap was highly regional: megafauna had last appearances in Alaska before humans first appeared, but did not have last appearances in the Great Lakes region until several thousand years after the first recorded human appearances. Overlap in the Great Lakes region exceeds uncertainty in radiocarbon measurements or methodological uncertainty and would be even greater with sampling-derived confidence intervals. The kriged maps of last megafaunal occurrence are consistent with climate as a primary driver in some areas, but we cannot eliminate human influence from all regions. The late Pleistocene megafaunal extinction was highly variable in timing and duration of human overlap across the continent, and future analyses should take these regional trends into account.

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Wright, H. E. "Faunal extinctions at the end of the Pleistocene." Reviews in Anthropology 13, no. 3 (June 1986): 223–35. http://dx.doi.org/10.1080/00988157.1986.9977783.

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Louys, Julien, Darren Curnoe, and Haowen Tong. "Characteristics of Pleistocene megafauna extinctions in Southeast Asia." Palaeogeography, Palaeoclimatology, Palaeoecology 243, no. 1-2 (January 2007): 152–73. http://dx.doi.org/10.1016/j.palaeo.2006.07.011.

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Field, Judith, and Stephen Wroe. "Aridity, faunal adaptations and Australian Late Pleistocene extinctions." World Archaeology 44, no. 1 (March 2012): 56–74. http://dx.doi.org/10.1080/00438243.2012.647572.

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Lundelius, Ernest L. "The implications of disharmonious assemblages for Pleistocene extinctions." Journal of Archaeological Science 16, no. 4 (July 1989): 407–17. http://dx.doi.org/10.1016/0305-4403(89)90015-0.

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Grayson, Donald K. "The chronology of North American late pleistocene extinctions." Journal of Archaeological Science 16, no. 2 (March 1989): 153–65. http://dx.doi.org/10.1016/0305-4403(89)90063-0.

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Davis, Matt. "What North America's skeleton crew of megafauna tells us about community disassembly." Proceedings of the Royal Society B: Biological Sciences 284, no. 1846 (January 11, 2017): 20162116. http://dx.doi.org/10.1098/rspb.2016.2116.

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Functional trait diversity is increasingly used to model future changes in community structure despite a poor understanding of community disassembly's effects on functional diversity. By tracking the functional diversity of the North American large mammal fauna through the End-Pleistocene megafaunal extinction and up to the present, I show that contrary to expectations, functionally unique species are no more likely to go extinct than functionally redundant species. This makes total functional richness loss no worse than expected given similar taxonomic richness declines. However, where current species sit in functional space relative to pre-anthropogenic baselines is not random and likely explains ecosystem functional changes better than total functional richness declines. Prehistoric extinctions have left many extant species functionally isolated and future extinctions will cause even more rapid drops in functional richness.

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Jordan, Gregory J. "Contrasts between the Climatic Ranges of Fossil and Extant Taxa: Causes and Consequences for Palaeoclimatic Estimates." Australian Journal of Botany 45, no. 3 (1997): 465. http://dx.doi.org/10.1071/bt96038.

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Many palaeoclimate estimates are based on the climatic ranges of the nearest living relatives (NLRs) of fossils. If the climatic ranges of the true NLRs of the taxa in a fossil assemblage do not overlap, then the past climatic ranges of some of the fossil taxa are different from the ranges of their NLRs. Discrepancies between the climatic ranges of the inferred NLRs of co-occurring fossils are common, particularly in assemblages older than the Middle Pleistocene. Evidence from Early Pleistocene Tasmania indicates that many anomalies are caused by extinct species, or at least extinct genotypes. It is likely that pre-Quaternary fossil deposits will contain more extinct taxa. Most of the extinct Early Pleistocene taxa have warm climate NLRs, but they appear to have occurred in climates no warmer than modern climates in western Tasmania. Sometimes NLR approaches in climate reconstruction appear to be biased by extinctions of ecotypes and species, especially ones caused by the Pleistocene glacial–interglacial cycles. Extinctions also mean that it is difficult to identify palaeoclimates that are different from any modern climate.

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Budd, Ann F., Thomas A. Stemann, and Kenneth G. Johnson. "Stratigraphic distributions of genera and species of Neogene to Recent Caribbean reef corals." Journal of Paleontology 68, no. 5 (September 1994): 951–77. http://dx.doi.org/10.1017/s0022336000026585.

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To document evolutionary patterns in late Cenozoic Caribbean reef corals, we compiled composite stratigraphic ranges of 49 genera and 175 species using Neogene occurrences in the Cibao Valley sequence of the northern Dominican Republic and faunal lists for 24 Miocene to Recent sites across the Caribbean region. This new compilation benefits in particular from increased sampling at late Miocene to early Pleistocene sites and from increased resolution and greater taxonomic consistency provided by the use of morphometric procedures in species recognition.Preliminary examination and quantitative analysis of origination and extinction patterns suggest that a major episode of turnover took place between 4 and 1 Ma during Plio-Pleistocene time. During the episode, extinctions were approximately simultaneous in species of all reef-building families, except the Mussidae. Most strongly affected were the Pocilloporidae (Stylophora and Pocillopora), Agariciidae (Pavona and Gardineroseris), and free-living members of the Faviidae and Meandrinidae. At the genus level, mono- and paucispecific as well as more speciose genera became regionally extinct. Many of the extinct genera live today in the Indo-Pacific region, and some are important components of modern eastern Pacific reefs. Global extinctions were concentrated in free-living genera. During the turnover episode, no new genera or higher taxa arose. Instead, new species originated within the surviving Caribbean genera at approximately the same time as the extinctions, including many dominant modern Caribbean reef-building corals (e.g., Acropora palmata and the Montastraea annularis complex).Excluding this episode, the taxonomic composition of the Caribbean reef-coral fauna remained relatively unchanged during the Neogene. Minor exceptions include: 1) high originations in the Agariciidae and free-living corals during late Miocene time; and 2) regional or global extinctions of several important Oligocene Caribbean reef builders during early to middle Miocene time.

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Cramb, Jonathan, Gilbert J. Price, and Scott A. Hocknull. "Short-tailed mice with a long fossil record: the genusLeggadina(Rodentia: Muridae) from the Quaternary of Queensland, Australia." PeerJ 6 (September 21, 2018): e5639. http://dx.doi.org/10.7717/peerj.5639.

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The genusLeggadina(colloquially known as ‘short-tailed mice’) is a common component of Quaternary faunas of northeastern Australia. They represent a member of the Australian old endemic murid radiation that arrived on the continent sometime during the late Cenozoic. Here we describe two new species of extinctLeggadinafrom Quaternary cave deposits as well as additional material of the extinctLeggadina macrodonta.Leggadina irvinisp. nov. recovered from Middle-Upper (late) Pleistocene cave deposits near Chillagoe, northeastern Queensland, is the biggest member of the genus, being substantially larger than any other species so far described.Leggadina webbisp. nov. from Middle Pleistocene cave deposits at Mount Etna, central eastern Queensland, shares features with the oldest species of the genus, the Early PleistoceneL. gregoriensis. Based on the current palaeoecological interpretation of the type locality,L. webbi, represents the only member of the genus that inhabited rainforest. The succession ofLeggadinaspecies through the late Quaternary suggests an ecological replacement of the extinct large-bodiedL. irviniwith the extant, small-bodiedL. lakedownesisat Chillagoe. At Mt. Etna, the extinct rainforest speciesL. webbiis replaced with the extant xeric-adaptedL. forrestiduring the latest Middle Pleistocene. This replacement is associated with a mid-Pleistocene shift towards progressive intensifying seasonal and arid climates. Our study adds to the growing list of small-bodied faunal extinctions during the late Quaternary of northern Australia.

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Lima-Ribeiro, Matheus S., Joaquín Hortal, Sara Varela, and José Alexandre F. Diniz-Filho. "Constraint envelope analyses of macroecological patterns reveal climatic effects on Pleistocene mammal extinctions." Quaternary Research 82, no. 1 (July 2014): 260–69. http://dx.doi.org/10.1016/j.yqres.2014.02.003.

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AbstractQuantitative analysis of macroecological patterns for late Pleistocene assemblages can be useful for disentangling the causes of late Quaternary extinctions (LQE). However, previous analyses have usually assumed linear relationships between macroecological traits, such as body size and range size/range shift, that may have led to erroneous interpretations. Here, we analyzed mammalian datasets to show how macroecological patterns support climate change as an important driver of the LQE, which is contrary to previous analyses that did not account for more complex relationships among traits. We employed quantile regression methods that allow a detailed and fine-tuned quantitative analysis of complex macroecological patterns revealed as polygonal relationships (i.e., constraint envelopes). We showed that these triangular-shaped envelopes that describe the macroecological relationship between body size and geographical range shift reflect nonrandom extinction processes under which the large-bodied species are more prone to extinction during events of severe habitat loss, such as glacial/interglacial transitions. Hence, we provide both a theoretical background and methodological framework to better understand how climate change induces body size-biased species sorting and shapes complex macroecological patterns.

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Rick, Torben C., John S. Wah, and Jon M. Erlandson. "Re-evaluating the origins of late Pleistocene fire areas on Santa Rosa Island, California, USA." Quaternary Research 78, no. 2 (July 21, 2012): 353–62. http://dx.doi.org/10.1016/j.yqres.2012.06.006.

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AbstractAt the close of the Pleistocene, fire regimes in North America changed significantly in response to climate change, megafaunal extinctions, anthropogenic burning and possibly, even an extraterrestrial impact. On California's Channel Islands, researchers have long debated the nature of late Pleistocene “fire areas,” discrete red zones in sedimentary deposits, interpreted by some as prehistoric mammoth-roasting pits created by humans. Further research found no evidence that these red zones were cultural in origin, and two hypotheses were advanced to explain their origin: natural fires and groundwater processes. Radiocarbon dating, X-ray diffraction analysis, and identification of charcoal from six red zones on Santa Rosa Island suggest that the studied features date between ~ 27,500 and 11,400 cal yr BP and resulted from burning or heating, not from groundwater processes. Our results show that fire was a component of late Pleistocene Channel Island ecology prior to and after human colonization of the islands, with no clear evidence for increased fire frequency coincident with Paleoindian settlement, extinction of pygmy mammoths, or a proposed Younger Dryas impact event.

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Louys, Julien, Gilbert J. Price, and Sue O’Connor. "Direct dating of Pleistocene stegodon from Timor Island, East Nusa Tenggara." PeerJ 4 (March 10, 2016): e1788. http://dx.doi.org/10.7717/peerj.1788.

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Stegodons are a commonly recovered extinct proboscidean (elephants and allies) from the Pleistocene record of Southeast Asian oceanic islands. Estimates on when stegodons arrived on individual islands and the timings of their extinctions are poorly constrained due to few reported direct geochronological analyses of their remains. Here we report on uranium-series dating of a stegodon tusk recovered from the Ainaro Gravels of Timor. The six dates obtained indicate the local presence of stegodons in Timor at or before 130 ka, significantly pre-dating the earliest evidence of humans on the island. On the basis of current data, we find no evidence for significant environmental changes or the presence of modern humans in the region during that time. Thus, we do not consider either of these factors to have contributed significantly to their extinction. In the absence of these, we propose that their extinction was possibly the result of long-term demographic and genetic declines associated with an isolated island population.

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Davis, Matt, Søren Faurby, and Jens-Christian Svenning. "Mammal diversity will take millions of years to recover from the current biodiversity crisis." Proceedings of the National Academy of Sciences 115, no. 44 (October 15, 2018): 11262–67. http://dx.doi.org/10.1073/pnas.1804906115.

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The incipient sixth mass extinction that started in the Late Pleistocene has already erased over 300 mammal species and, with them, more than 2.5 billion y of unique evolutionary history. At the global scale, this lost phylogenetic diversity (PD) can only be restored with time as lineages evolve and create new evolutionary history. Given the increasing rate of extinctions however, can mammals evolve fast enough to recover their lost PD on a human time scale? We use a birth–death tree framework to show that even if extinction rates slow to preanthropogenic background levels, recovery of lost PD will likely take millions of years. These findings emphasize the severity of the potential sixth mass extinction and the need to avoid the loss of unique evolutionary history now.

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Brook, B. W., and D. M. J. S. Bowman. "Explaining the Pleistocene megafaunal extinctions: Models, chronologies, and assumptions." Proceedings of the National Academy of Sciences 99, no. 23 (November 4, 2002): 14624–27. http://dx.doi.org/10.1073/pnas.232126899.

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Hayward, Bruce W. "Global deep-sea extinctions during the Pleistocene ice ages." Geology 29, no. 7 (2001): 599. http://dx.doi.org/10.1130/0091-7613(2001)029<0599:gdsedt>2.0.co;2.

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Solow, A. R., D. L. Roberts, and K. M. Robbirt. "On the Pleistocene extinctions of Alaskan mammoths and horses." Proceedings of the National Academy of Sciences 103, no. 19 (May 1, 2006): 7351–53. http://dx.doi.org/10.1073/pnas.0509480103.

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Ripple, William J., and Blaire Van Valkenburgh. "Linking Top-down Forces to the Pleistocene Megafaunal Extinctions." BioScience 60, no. 7 (July 2010): 516–26. http://dx.doi.org/10.1525/bio.2010.60.7.7.

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Barnes, I. "Dynamics of Pleistocene Population Extinctions in Beringian Brown Bears." Science 295, no. 5563 (March 22, 2002): 2267–70. http://dx.doi.org/10.1126/science.1067814.

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Faith, J. Tyler. "Late Pleistocene and Holocene mammal extinctions on continental Africa." Earth-Science Reviews 128 (January 2014): 105–21. http://dx.doi.org/10.1016/j.earscirev.2013.10.009.

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Tello, Francisco, José R. Verdú, Michele Rossini, and Mario Zunino. "Onthophagus pilauco sp. nov. (Coleoptera, Scarabaeidae): evidence of beetle extinction in the Pleistocene–Holocene transition in Chilean Northern Patagonia." ZooKeys 1043 (June 15, 2021): 133–45. http://dx.doi.org/10.3897/zookeys.1043.61706.

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The South American Pleistocene–Holocene transition has been characterized by drastic climatic and diversity changes. These rapid changes induced one of the largest and most recent extinctions in the megafauna at the continental scale. However, examples of the extinction of small animals (e.g., insects) are scarce, and the underlying causes of the extinction have been little studied. In this work, a new extinct dung beetle species is described from a late Pleistocene sequence (~15.2 k cal yr BP) at the paleoarcheological site Pilauco, Chilean Northern Patagonia. Based on morphological characters, this fossil is considered to belong to the genus Onthophagus Latreille, 1802 and named Onthophagus pilaucosp. nov. We carried out a comprehensive revision of related groups, and we analyzed the possible mechanism of diversification and extinction of this new species. We hypothesize that Onthophagus pilaucosp. nov. diversified as a member of the osculatii species-complex following migration processes related to the Great American Biotic Interchange (~3 Ma). The extinction of O. pilaucosp. nov. may be related to massive defaunation and climatic changes recorded in the Plesitocene-Holocene transition (12.8 k cal yr BP). This finding is the first record of this genus in Chile, and provides new evidence to support the collateral-extinction hypothesis related to the defaunation.

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Vermeij, Geerat J. "Geographical restriction as a guide to the causes of extinction: the case of the cold northern oceans during the Neogene." Paleobiology 15, no. 4 (1989): 335–56. http://dx.doi.org/10.1017/s0094837300009544.

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Geographical restriction to refuges implies the regional extinction of taxa in areas of the previous range falling outside the refuge. A comparison of the circumstances in the refuge with those in areas from which the taxa were eliminated is potentially informative for pinpointing the causes of extinction. A synthesis of data on the geographical and stratigraphical distributions of cool-water molluscs of the North Pacific and North Atlantic Oceans during the late Neogene reveals four patterns of geographical restriction, at least two of which imply that climatic cooling was not the only cause of extinction during the last several million years. These four patterns are (1) the northwestern Pacific restriction, involving 15 taxa whose amphi-Pacific distributions during the late Neogene became subsequently restricted to the Asian side of the Pacific; (2) the northwestern Atlantic restriction, involving six taxa whose early Pleistocene distribution is inferred to have been amphi-Atlantic, but whose present-day and late Pleistocene ranges are confined to the northwestern Atlantic; (3) a vicariant Pacific pattern, in which many ancestral amphi-Pacific taxa gave rise to separate eastern and western descendants; and (4) the circumboreal restriction, involving six taxa whose early Pleistocene distribution, encompassing both the Atlantic and Pacific Oceans, became subsequently limited to the North Pacific. Like the Pliocene extinctions in the Atlantic, previously studied by Stanley and others, the vicariant Pacific pattern is most reasonably interpreted as having resulted from regional extinction of northern populations in response to cooling. The northwestern Pacific and Atlantic restrictions, however, cannot be accounted for in this way. In contrast to the northeastern margins of the Pacific and Atlantic, the northwestern margins are today characterized by wide temperature fluctuations and by extensive development of shore ice in winter. Northeastern, rather than northwestern, restriction would be expected if cooling were the overriding cause of regional extinction. Among the other possible causes of extinction, only a decrease in primary productivity can account for the observed northwestern and circumboreal patterns of restriction. Geographical patterns of body size and the distribution of siliceous deposits provide supporting evidence that primary productivity declined after the Miocene in the northeastern Pacific, but remained high in the northwestern Pacific, and that productivity in the Pacific is generally higher than it is in the Atlantic. The patterns of geographical restriction in the northern oceans thus provide additional support to previous inferences that reductions in primary productivity have played a significant role in marine extinctions.

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Diniz-Filho, J. A. F. "Macroecological analyses support an overkill scenario for late Pleistocene extinctions." Brazilian Journal of Biology 64, no. 3a (August 2004): 407–14. http://dx.doi.org/10.1590/s1519-69842004000300005.

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The extinction of megafauna at the end of Pleistocene has been traditionally explained by environmental changes or overexploitation by human hunting (overkill). Despite difficulties in choosing between these alternative (and not mutually exclusive) scenarios, the plausibility of the overkill hypothesis can be established by ecological models of predator-prey interactions. In this paper, I have developed a macroecological model for the overkill hypothesis, in which prey population dynamic parameters, including abundance, geographic extent, and food supply for hunters, were derived from empirical allometric relationships with body mass. The last output correctly predicts the final destiny (survival or extinction) for 73% of the species considered, a value only slightly smaller than those obtained by more complex models based on detailed archaeological and ecological data for each species. This illustrates the high selectivity of Pleistocene extinction in relation to body mass and confers more plausibility on the overkill scenario.

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Journal articles on the topic 'Pleistocene extinctions'

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