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Gigantic lion, Panthera leo, from the Pleistocene of Natodomeri, eastern Africa
- Fredrick K. Manthi, Francis H. Brown, Michael J. Plavcan, Lars Werdelin
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- Journal:
- Journal of Paleontology / Volume 92 / Issue 2 / March 2018
- Published online by Cambridge University Press:
- 09 November 2017, pp. 305-312
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The partial skull of a lion from Natodomeri, northwest Kenya is described. The Natodomeri sites are correlated with Member I of the Kibish Formation, dated to between 195 ka and ca. 205 ka. The skull is remarkable for its very great size, equivalent to the largest cave lions (Panthera spelaea [Goldfuss, 1810]) of Pleistocene Eurasia and much larger than any previously known lion from Africa, living or fossil. We hypothesize that this individual represents a previously unknown population or subspecies of lion present in the late Middle and Late Pleistocene of eastern Africa rather than being an indication of climate-driven size increase in lions of that time. This raises questions regarding the extent of our understanding of the pattern and causes of lion evolution in the Late Pleistocene.
Contributors
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- By Maria Alejandra Abello, Adriana Albino, Kari L. Allen, Juan I. Areta, M. Susana Bargo, Thomas M. Bown, Mariana Brea, Adriana M. Candela, Guillermo H. Cassini, Esperanza Cerdeño, Federico J. Degrange, Maria T. Dozo, Marcos D. Ercoli, Juan C. Fernicola, John G. Fleagle, Analía M. Forasiepi, Miguel Griffin, Matthew T. Heizler, Ari Iglesias, Richard F. Kay, E. Christopher Kirk, Verónica Krapovickas, Michael Malinzak, Sergio D. Matheos, Nahuel A. Muñoz, Barbara Nash, Jorge I. Noriega, Edgardo Ortiz-Jaureguizar, Ana Parras, María E. Pérez, Michael E. Perkins, Jonathan M. G. Perry, J. Michael Plavcan, Francisco J. Prevosti, M. Sol Raigemborn, Luciano L. Rasia, Adán A. Tauber, Marcelo F. Tejedor, Néstor Toledo, Guillermo F. Turazzini, Amalia L. Villafañe, Sergio F. Vizcaíno, Alejandro F. Zucol
- Edited by Sergio F. Vizcaíno, Richard F. Kay, Duke University, North Carolina, M. Susana Bargo
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- Book:
- Early Miocene Paleobiology in Patagonia
- Published online:
- 05 June 2013
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- 11 October 2012, pp vi-viii
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16 - Paleobiology of Santacrucian primates
- Edited by Sergio F. Vizcaíno, Richard F. Kay, Duke University, North Carolina, M. Susana Bargo
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- Early Miocene Paleobiology in Patagonia
- Published online:
- 05 June 2013
- Print publication:
- 11 October 2012, pp 306-330
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Summary
Abstract Over the past century, the Santa Cruz Formation of coastal Argentina (late Early Miocene) has yielded a remarkable collection of platyrrhine primates. With few notable exceptions, most of the specimens have been included in
Ameghino, 1891, a stem platyrrhineHomunculus patagonicus . Homunculus patagonicus was approximately 1.5 to 2.5 kg in body mass, about the size of a living saki monkey (Pithecia ) or a femaleCebus . Molar structure indicates that the diet consisted of a mixture of fruit and leaves. A deep jaw, large postcanine tooth roots, large postglenoid processes and moderately large chewing muscle attachments (i.e. massive zygomatic arches, sculpted temporalis origins) suggest that physically resistant foods were key components of the diet. Heavy tooth wear suggests large amounts of ingested silica or exogenous abrasives. Incisor morphology suggests that exudate harvesting may have been part of the behavioral repertoire, although not a specialization. The canines were small, providing no evidence of sclerocarpic foraging. Canines were sexually dimorphic, suggesting that the taxon experienced some intrasexual competition rather than being solitary or pair-bonded. Brain size was small and the frontal cortical region was proportionately small. From the small size and structure of the orbits, the structure of the organ of hearing, the reduced olfactory fossae and the relatively large infraorbital foramina, we infer thatHomunculus was probably diurnal, with acute vision and hearing, but with a poor sense of smell and little reliance on tactile vibrissae.Homunculus was an above-branch arboreal quadruped with leaping abilities. The semicircular canals show evidence of considerable agility, reinforcing the inference of leaping behavior. The overall locomotor repertoire is not unlike that of the forest-dwelling extant saki monkeyPithecia . Considered together, the mosaic of dietary and locomotor morphology inHomunculus suggests thatHomunculus inhabited an environment – as compared with earlier Colhuehuapian and Pinturan primate habitats – shifting towards greater seasonality in patchy forests near river courses.
14 - Seasonality, social organization, and sexual dimorphism in primates
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- By J. Michael Plavcan, Department of Anthropology University of Arkansas, Fayetteville AR 72701 USA, Carel P. van Schaik, Anthropologisches Institut University of Zurich, Winterthurerstrasse 190 CH-8057, Zurich, Switzerland, W. Scott McGraw, Department of Anthropology Ohio State University, Columbus OH 43210 USA
- Edited by Diane K. Brockman, University of North Carolina, Charlotte, Carel P. van Schaik, Universität Zürich
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- Book:
- Seasonality in Primates
- Published online:
- 10 August 2009
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- 17 November 2005, pp 401-442
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Summary
Introduction
Primates live in habitats in which food abundance and other resources fluctuate over time, usually on a seasonal basis, and space. This variation affects the lives of primates in many ways, from behavioral ecology to reproduction (see Chapters 3 and 11). In this chapter, we explore how environmental and behavioral seasonality affect sexual dimorphism.
Sexual dimorphism in body and canine size among primates generally is viewed as primarily a consequence of sexual selection operating through the mechanism of male–male competition for mates (Leutenegger & Kelly 1977; Clutton-Brock et al. 1977; Kay et al. 1988; Plavcan & van Schaik 1992, 1997; Ford 1994; Lindenfors & Tullberg 1998) and modified by female choice for male traits (Plavcan 2004). Sexual dimorphism can be affected by environmental seasonality in two independent ways (see Fig. 14.1): first through the indirect impact of seasonality on the potential for mate monopolization (Mitani et al. 1996a; Nunn 1999; Pereira et al. 2000), and second through the direct impact of seasonality on male and female body size (Albrecht 1978; Turner et al. 1997). In the first case, phenological or climatic seasonality brings about the simultaneous presence of multiple cycling females due to reproductive seasonality and also may favor larger female group size. These effects in turn should affect the number of males present in a group, and patterns of male–male competition and resulting reproductive skew – in other words, several aspects of social organization and the mating system, all of which are tied to sexual dimorphism.
13 - Sexual selection, measures of sexual selection, and sexual dimorphism in primates
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- By J. Michael Plavcan, Department of Anthropology, University of Arkansas, Fayetteville, AR, USA
- Edited by Peter M. Kappeler, Deutsches Primatenzentrum, Göttingen, Germany, Carel P. van Schaik, Duke University, North Carolina
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- Sexual Selection in Primates
- Published online:
- 10 August 2009
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- 13 May 2004, pp 230-252
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Summary
INTRODUCTION
Sexual dimorphism in anthropoid primates is commonly viewed as a product of sexual selection (Clutton-Brock et al., 1977; Harvey et al., 1978; Gaulin & Sailer, 1984; Clutton-Brock, 1985; Milton, 1985; Rodman & Mitani, 1987; Kay et al., 1988; Ely & Kurland, 1989; Greenfield, 1992a, b; Plavcan & van Schaik, 1992, 1994, 1997; Ford, 1994; Martin et al., 1994; Mitani et al., 1996b; Lindenfors & Tullberg, 1998; Plavcan, 1999, 2001; Barton, 2000; Lindenfors, 2002a; Mitani et al., 2002). Yet dimorphism in anthropoids is highly variable, and is expressed not as a single character, but rather to different degrees in different traits. This naturally raises the question of whether this variation is owing to variation in the strength of sexual selection, phylogenetic effects or the action of other selective factors on the dimorphic characters. While numerous papers have examined the causes and correlates of dimorphism in anthropoids, the relative contribution of sexual selection and other factors to variation in dimorphism remains unclear.
Part of this problem lies in the way that both dimorphism and sexual selection are measured. Both of these variables are estimated with error, not only in a simple statistical sense, but also in the assumptions that are used to justify measures as appropriate for analysis. Some of these biases are obvious, while others are not. Thus, if dimorphism is poorly correlated with an estimate of sexual selection, we can legitimately ask whether dimorphism is affected by factors other than sexual selection, or whether our measures fail to capture variation in either sexual selection or the targets of sexual selection.
22 - The paleoecology of the Pikermian Biome and the savanna myth
- from PART IV - Palaeoenvironments: mammalian evidence
- Edited by Jorge Agustí, Institut de Paleontologia M. Crusafont, Sabadell, Spain, Lorenzo Rook, Università degli Studi di Firenze, Italy, Peter Andrews
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- Hominoid Evolution and Climatic Change in Europe
- Published online:
- 15 December 2009
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- 07 October 1999, pp 436-453
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Summary
Introduction
Many important Eurasian later Miocene localities are characterized by an abundance of species of aardvarks, hyenas, hyraxes, mastodons, hipparions, rhinoceroses, giraffes, and antelopes (Kurtén, 1952, 1971; Thenius, 1959). The combination of this type of species is only encountered in modern African savannas and therefore such Miocene faunas were originally interpreted to represent savannas (Gaudry, 1862–7; Osborn, 1910; Abel, 1927). More recently, such faunas have also been interpreted to represent savannas (Estes, 1971; Kurtén, 1952, 1971; Webb, 1983; Janis, 1982, 1989; de Bonis et al., 1992). The single and most influential character for interpreting extinct faunas as savannas throughout the Miocene is the presence of tall teeth (hypsodont teeth) in ungulates (Webb, 1983). Among all ungulates, the presence of hypsodont equids has been the most influential in determining the presence of savannas in the past (Simpson, 1951; Thenius, 1969; Kurtén, 1952, 1971; Webb, 1983; Janis, 1982, 1989; de Bonis et al., 1992; MacFadden, 1992).
These faunas have also been widely termed ‘hipparion faunas’ because they contain on the average four to seven species of hipparions (Kurtén, 1952, 1971; Sondaar, 1971; Berggren & Van Couvering, 1974; Woodburne, 1989). Hipparions were widespread and successful species throughout the World (Bernor et al., 1988, 1990; Woodburne, 1989). They were hypsodont equids with three toes and an isolated protocone. Most hipparions have been interpreted to ecologically resemble modern zebras and horses which graze and live in savannas and grasslands (Matthew, 1926; Simpson, 1951; Thenius, 1969; Janis, 1982; Webb, 1983; MacFadden, 1992). Other researchers have interpreted hipparions as species which inhabited woodlands (Bernor et al., 1988, 1990; Hayek et al., 1992).
9 - Mating systems, intrasexual competition and sexual dimorphism in primates
- Edited by P. C. Lee, University of Cambridge
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- Book:
- Comparative Primate Socioecology
- Published online:
- 24 August 2009
- Print publication:
- 13 June 1999, pp 241-270
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Summary
Many primates are sexually dimorphic. Collectively, sexual dimorphism refers to any character – behavioural, morphological or physiological – that differs between the sexes. Some primates show conspicuous differences in pelage and skin colour, and numerous musculoskeletal differences have been documented for a wide variety of species. However, most comparative studies of primate sexual dimorphism focus on body size and canine tooth size.
Strepsirhines and haplorhines differ fundamentally in dimorphism. Most male haplorhine primates are larger than females, and possess larger canine teeth. In contrast, most strepsirhine species are either monomorphic or only slightly dimorphic (Fig. 9.1). Consequently, most comparative studies of primate sexual dimorphism focus on haplorhines.
Dimorphism, mating systems and intrasexual competition
Sexual dimorphism in haplorhine primates is widely viewed as a product of sexual selection. Sexual selection comprises two broad mechanisms: mate choice and mate competition (Andersson, 1994). Mate choice in primates is usually referred to as ‘female choice’. There is clearly evidence that female choice plays a role in the evolution of sexual dimorphism in primates (Boinski, 1987; Richard, 1992). However, because female choice is difficult to quantify, and data are not available for most species, the exact role that it plays in explaining interspecific variation in dimorphism is currently unknown (Small, 1989).
Primate sexual dimorphism is commonly viewed as a product of male mate competition. Because males are effectively limited in their reproductive success by the number of females that they can inseminate, large differences in male reproductive success will occur if some males can exclude others from access to females. Males should therefore compete for access to females.