| 1. |
- Andersson, Ki, et al.
(author)
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Carnivora from the Late Miocene of Lantian, China
- 2005
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In: Vertebrata PalAsiatica. ; 43, s. 256-271
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Journal article (peer-reviewed)abstract
- Sediments of the Bahe and Lantian formations, Lantian area, Shaanxi Province, China, have produced a large number of mammalian fossils. This Late Miocene sequence provides evidence for a period of major changes in the physical environment of the region. The carnivoran fossils are described and analyzed herein. The following species are present: lctitherium viverrinum, Hyaenictitherium cf . H. wongii and Adcrocuta eximia ( Hyaenidae) , cf. Metailurus major and cf. Metailurus parvulus ( Felidae) . Although a difference in the composition of the carnivoran fauna is noted towards the boundary between the Bahe Formation (lower) and Lantian Formation (upper), the cause of this is yet to be determined.
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| 2. |
- Cote, Susanne M., et al.
(author)
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The enigmatic Early Miocene mammal Kelba and its relationship to the order Ptolemaiida
- 2007
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In: Proceedings of the National Academy of Sciences of the United States of America. - : Proceedings of the National Academy of Sciences. - 0027-8424 .- 1091-6490. ; 104, s. 5510-5515
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Journal article (peer-reviewed)abstract
- Kelba quadeemae, a fossil mammal from the Early Miocene of East Africa, was originally named on the basis of three isolated upper molars. Kelba has previously been interpreted as a creodont, a pantolestid, an insectivoran, and a hemigaline viverrid. The true affinities of this taxon have remained unclear because of the limited material and its unique morphology relative to other Miocene African mammals. New material of Kelba from several East African Miocene localities, most notably a skull from the Early Miocene locality of Songhor in Western Kenya, permits analysis of the affinities of Kelba and documents the lower dentition of this taxon. Morphological comparison of this new material clearly demonstrates that Kelba is a member of the order Ptolemaiida, a poorly understood group whose fossil record was previously restricted to the Oligocene Fayum deposits of northern Egypt. Phylogenetic analysis supports the monophyly of the Ptolemaiida, including Kelba, and recovers two monophyletic clades within the order. We provide new family names for these groups and an emended diagnosis for the order. The discovery of ptolemaiidans from the Miocene of East Africa is significant because it extends the known temporal range of the order by >10 million years and the geographic range by >3,200 km. Although the higher-level affinities of the Ptolemaiida remain obscure, their unique morphology and distribution through a larger area of Africa (and exclusively Africa) lend support to the idea that Ptolemaiida may have an ancient African origin.
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| 3. |
- Lewis, Margaret E., et al.
(author)
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Patterns of change in in the Plio-Pleistocene carnivorans of eastern Africa: Implications for hominin evolution
- 2007
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In: Hominin environments in the East African Pliocene: An assessment of the faunal evidence. - New York : Springer-Verlag New York. ; , s. 77-105
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Book chapter (peer-reviewed)abstract
- This paper uses changes in origination and extinction rates and species richness of eastern African carnivorans through time to discuss issues related to the evolution of hominin behavior. To address the question of which taxa were most likely to have had competitive interactions with hominins, modern carnivorans were sorted into size classes based on shifts in behavior, ecology, and body mass. Four size classes were created, among which the two largest (21.5–100 kg and >100 kg) include those taxa whose behavior is most relevant to the evolution of hominin dietary behavior. Fossil taxa were then assigned to these size classes. A summary of the temporal range and reconstructed behavior and ecology of fossil members of the two largest size classes is presented. We discuss the relevance of each taxon to reconstructing hominin behavior and suggest that hominins must have evolved not only successful anti-predator strategies, but also successful strategies to avoid kleptoparasitism before carcass-based resources could become an important part of the diet. Although hominins were unlikely to have been top predators upon first entrance into the carnivore guild, effective anti-predator/anti-kleptoparasitism strategies in combination with the eventual evolution of active hunting would have increased the rank of hominin species within the guild. While the appearance of stone tools at 2.6 Ma has no apparent effect upon carnivorans, the appearance of Homo ergaster after 1.8 Ma may have been at least partly responsible for the decrease in the carnivoran origination rate and the increase in the extinction rate at this time. The behavior of H. ergaster , climate change, and concomitant changes in prey species richness may have caused carnivoran species richness to drop precipitously after 1.5 Ma. In this situation, even effective kleptoparasitism by H. ergaster may have been enough to drive local populations of carnivorans that overlapped with hominins in dietary resources to extinction. Possibly as a result, the modern guild, which evolved within the last few hundred thousand years, is composed primarily of generalists. Although the impact of H. sapiens on the carnivoran guild cannot be assessed due to a lack of carnivoran fossils from this time period, one might not consider the modern carnivore guild to be complete until the appearance of our species approximately 200,000 years ago.
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| 4. |
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| 5. |
- Pujos, F., et al.
(author)
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A peculiar climbing Megalonychidae from the Pleistocene of Peru and its implications for sloth history
- 2007
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In: Zoological Journal of the Linnean Society. - 0024-4082 .- 1096-3642. ; 149, s. 179-235
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Journal article (peer-reviewed)abstract
- The Xenarthra, particularly the Tardigrada, are with the Notoungulata and Marsupialia among the most diversified South American mammals. Lujanian South American Land Mammal Age localities from the coastal Piedra Escrita site and Andean Casa del Diablo Cave, Peru, have yielded three specimens of the Megalonychidae Diabolotherium nordenskioldi gen. nov. This singular fossil sloth exhibits a peculiar mosaic of cranial and postcranial characters. Some are considered convergent with those of other sloths (e.g. 5/4 quadrangular teeth, characteristic of Megatheriidae), whereas others clearly indicate climbing capabilities distinct from the suspensory mode of extant sloths. The arboreal mode of life of D. nordenskioldi is suggested by considerable mobility of the elbow, hip, and ankle joints, a posteriorly convex ulna with an olecranon shorter than in fossorial taxa, a radial notch that faces more anteriorly than in other fossil sloths and forms an obtuse angle with the coronoid process (which increases the range of pronation– supination), a proximodistally compressed scaphoid, and a wide range of digital flexion. D. nordenskioldi underscores the great adaptability of Tardigrada: an arboreally adapted form is now added to the already known terrestrial, subarboreal, and aquatic (marine and freshwater) fossil sloths. A preliminary phylogenetic analysis of the Tardigrada confirmed the monophyly of Megatherioidea, Nothrotheriidae, Megatheriidae, and Megalonychidae, in which Diabolotherium is strongly nested.
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| 6. |
- Sardella, Raffaele, et al.
(author)
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Amphimachairodus (Felidae, Mammalia) from Sahabi (latest Miocene - earliest Pliocene, Libya), with a review of African Miocene Machairodontinae
- 2007
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In: Rivista italiana di paleontologia e stratigrafia. - 0035-6883 .- 2039-4942. ; 113, s. 67-77
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Journal article (peer-reviewed)abstract
- We describe and illustrate a partial skull and mandible of a large sabertooth cat from Sahabi, Libya, and refer it to Amphimachairodus aff. A. kabir. A review shows the Miocene Machairodontinae from Africa to be a heterogeneous assemblage, with both small and large forms spanning the entire Late Miocene. The Sahabi form belongs to the group of larger sized taxa, along with A. kabir from Chad and some previously undescribed specimens from the Wembere-Manonga Formation, Tanzania. Both the Sahabi and Chad specimens have relatively slender lower carnassials, similarly to Homotherium, though derived features of the skull and mandible suggest that they are not in the direct ancestry of that genus.
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| 7. |
- Strömberg, C. A. E., et al.
(author)
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Palaeoecology of a Middle Miocene lake in China: preliminary interpretations based on phytoliths from the Shanwang Basin
- 2007
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In: Vertebrata PalAsiatica. ; 45, s. 145-160
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Journal article (peer-reviewed)abstract
- The lacustrine Early to Middle Miocene Shanwang Formation contains an exceptionally well preserved biota including insects, plants, and vertebrates that has been subject to intense study. Palaeoecological work on plant macrofossils and palynofloras indicate that the locality represents a forest under a humid, warm-temperate to subtropical climate that remained rather stable during the deposition of the formation. This interpretation is supported by fossil vertebrates such as bats and tapirs discovered in the Shanwang section. However, to date no information has been available on the presence, abundance, and taxonomic composition of grasses at this locality. Here, we report on phytoliths extracted from six samples from the Shanwang Formation, providing new evidence of the vegetation that grew around the lake. The phytolith assemblages contain well-preserved and abundant grass phytoliths, forest indicator phytoliths from dicotyledonous plants, and infrequent palm phytoliths. The grass phytoliths consist of forms produced by C,IC4 PACCAD grasses and pooids, with a minor component of morphotypes thought to derive from closed-habitat grasses. Our preliminary interpretation of these phytolith assemblages is that they reflect a lake-side wooded habitat and abundant helophytic to mesophytic grasses, with drier areas supporting pooid (and PACCAD) grasses. The data support the reconstruction of the Miocene Shanwang region as more humid and equable than presently. The Shanwang phytolith assemblages contrast with Miocene lacustrine phytolith assemblages from Turkey and the Great Plains of North America, which indicate grass communities characterized by diverse C3 pooids and different types of PACCAD grasses. Future research will determine whether this variability reflects large-scale biogeographic differences in grass communities or local, microclimate-related variation.
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| 8. |
- Strömberg, C. A. E., et al.
(author)
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The spread of grass-dominated habitats in the Eastern Mediterranean during the Cainozoic: phytolith evidence
- 2007
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In: Palaeogeography, Palaeoclimatology, Palaeoecology. - : Elsevier BV. - 0031-0182 .- 1872-616X. ; 250, s. 18-49
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Journal article (peer-reviewed)abstract
- The arrival of hipparionine horses in the eastern Mediterranean region around 11 Ma was traditionally thought to mark the simultaneous westward expansion of savanna vegetation across Eurasia. However, recent paleoecological reconstructions based on tooth wear, carbon isotopes, and functional morphology indicate that grasses played a minor role in Late Miocene ecosystems of the eastern Mediterranean, which were more likely dry woodlands or forests. The scarcity of grass macrofossils and pollen in Miocene floras of Europe and Asia Minor has been used to support this interpretation. Based on the combined evidence, it has therefore been suggested that Late Miocene ungulate faunal change in the eastern Mediterranean signals increased aridity and landscape openness, but not necessarily the development of grass-dominated habitats. To shed newlight on the Miocene evolution of eastern Mediterranean ecosystems, we used phytolith assemblages preserved in direct association with faunas as a proxy for paleovegetation structure (grassland vs. forest).We extracted phytoliths and other biogenic silica fromsediment samples fromwell-known Early to Late Miocene (∼20–7Ma) faunal localities in Greece, Turkey, and Iran. In addition, a Middle Eocene sample from Turkey yielded phytoliths and served as a baseline comparison for vegetation inference. Phytolith analysis showed that the Middle Eocene assemblage consists of abundant grass phytoliths (grass silica short cells) interpreted as deriving from bambusoid grasses, as well as diverse forest indicator phytoliths from dicotyledonous angiosperms and palms, pointing to the presence of a woodland or forest with abundant bamboos. In contrast, the Miocene assemblages are dominated by diverse silica short cells typical of pooid open-habitat grasses. Forest indicator phytoliths are also present, but are rare in the Late Miocene (9–7 Ma) assemblages. Our analysis of the Miocene grass community composition is consistent with evidence from stable carbon isotopes from paleosols and ungulate tooth enamel, showing that C4 grasses were rare in the Mediterranean throughout the Miocene. These data indicate that relatively open habitats had become common in Turkey and surrounding areas by at least the Early Miocene (∼20 Ma), N7 million years before hipparionine horses reached Europe and arid conditions ensued, as judged by faunal data.
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| 9. |
- Turner, Alan, et al.
(author)
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Taxonomy and evolutionary patterns in the fossil Hyaenidae of Europe
- 2008
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In: Geobios. - : Elsevier BV. - 0016-6995 .- 1777-5728. ; 41, s. 677-687
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Journal article (peer-reviewed)abstract
- We review the larger pattern of appearance of the Hyaenidae in Europe and outline their part in the turnover of the guild of larger Carnivora that occurs across the Miocene–Pliocene boundary. The earliest record of the family is in MN4, although the patchy nature of the earliest records makes it difficult to be certain about the continent of origin. There is a clear pattern of morphological evolution over that long timespan, from the earliest viverrid- and herpestid-like forms through dog-like and more cursorial taxa to the larger, bone-crunching animals of the later Miocene and the Pliocene–Pleistocene epochs. Miocene dog-like hyaenas may indicate that social hunting had emerged by that time, while the appearance of larger species means that hyaena-accumulated bone assemblages may potentially occur in any late Miocene to Pleistocene locality.
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| 10. |
- Werdelin, Lars
(author)
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Biogeographic relationships of African carnivoran faunas 7-1.2 Ma.
- 2008
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In: Comptes rendus. Palevol. - : Elsevier BV. - 1631-0683 .- 1777-571X. ; 7, s. 645-656
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Journal article (peer-reviewed)abstract
- This study analyses the carnivore component of African fossil faunas from three time slices: 7–5 Ma, 4–3 Ma, and 2.5–1.2 Ma, using cluster analysis and principal coordinate analysis (PCO) of presence/absence data on genera. The faunas mostly cluster by time slice, with the exception of Laetoli (Tanzania) and Ahl al Oughlam (Morocco), which differ from all other faunas. The separation during the Late Miocene of a Chado–Libyan bioprovince from the remainder of Africa is supported. No such distinctions are present in the other time slices. Taxonomic distance is not generally correlated with geographic distance, though if Langebaanweg is removed from the 7–5 Ma time slice, the correlation at that time is significant. Comparison of these paleontological results with phylogeographic studies of modern species leads to some general comments on the analytic power of the fossil record with regard to interregional migrations.
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