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1.
Deer (Cervidae) have a long evolutionary history dating back to the Early Miocene, around 19 million years ago. The best known fossils to document this history belong to European taxa, which all bear cranial appendages more or less similar to today's deer antlers. Despite the good fossil record, relationships of the earliest stem deer and earliest crown deer are much debated. This hampers precise calibration against the independent evidence of the fossil record in molecular clock analyses. While much has been written on the Early and Middle Miocene deer, only two phylogenetic analyses have been performed on these taxa to date mostly based on cranial appendage characters. Because the petrosal bone and bony labyrinth have been shown to be relevant for phylogeny in ruminants, we describe for the first time these elements for four iconic early cervids from Europe (Procervulus dichotomus, Heteroprox larteti, Dicrocerus elegans and Euprox furcatus) and include them in a phylogenetic analysis based on the ear region exclusively. The analysis recovered E. furcatus in a sister position to the living red deer (Cervus elaphus). Further, it placed D. elegans in a sister position to Euprox + Cervus and a clade Procervulinae that includes P. dichotomus and H. larteti, in sister position to all other deer. The inclusion of E. furcatus in crown Cervidae, which was previously suggested based on antler morphology, cannot be ruled out here but needs a more comprehensive comparison to other crown deer to be confirmed. J. Morphol. 277:1329–1338, 2016. © 2016 Wiley Periodicals, Inc.  相似文献   

2.
The site of Cessaniti (Vibo Valentia, Italy) has been well known since the 19th century for the richness and good preservation of its Miocene fauna and flora. The sedimentary succession of the site represents a paralic system that evolved toward an open-marine environment recording the Tortonian transgression. The fossil assemblage contains rich invertebrate (corals, bivalves, gastropods, brachiopods, echinoids, benthic and planktonic foraminifers) and vertebrate faunas (proboscideans, rhinoceroses, giraffids, bovids, sirenids, marine turtles, and fish remains). The fossils recovered at the Cessaniti site have a relevant role in phylogenetic studies and paleogeographic reconstructions of Late Miocene environments of the southern Italy. This research is focused on the microstructure and preservation state of the fossil bones. Samples of Metaxytherium sp. bones have been analyzed to understand the diagenetic profile of the bone assemblages that characterizes the taphonomic history of the Cessaniti site. The analyses provided a comprehensive account of how bone mineral (bioapatite) has been altered and demonstrated that the post-burial processes did not significantly affect the micromorphological and biogeochemical features of the bones. The excellent preservation state of the bones strengthens the importance of the Cessaniti site for studies of the Mediterranean Miocene vertebrate fauna.  相似文献   

3.
The horn fly Haematobia irritans (Diptera: Muscidae) is a blood obligate ectoparasite of bovids that causes annual losses to the U.S. beef cattle industry of over US$1.75 billion. Climate warming, the anthropogenic dispersion of bovids and the cross‐breeding of beef cattle with other bovid species may facilitate novel horn fly–host interactions. In particular, hybridizing yaks [Bos grunniens (Artiodactyla: Bovidae)] with beef cows (Bos taurus) for heterosis and carcass improvements may increase the exposure of yak × beef hybrids to horn flies. The present paper reports on the collection of digital images of commingled beef heifers (n = 12) and F1 yak × beef hybrid bovids (heifers, n = 7; steers, n = 5) near Laramie, Wyoming (~ 2200 m a.s.l.) in 2018. The total numbers of horn flies on beef heifers and F1 yak × beef heifers [mean ± standard error (SE): 88 ± 13 and 70 ± 17, respectively] did not differ significantly; however, F1 yak × beef steers had greater total horn fly abundance (mean ± SE: 159 ± 39) than female bovids. The present report of this experiment is the first such report in the literature and suggests that F1 yak × beef bovids are as susceptible as cattle to horn fly parasitism. Therefore, similar monitoring and treatment practices should be adopted by veterinarians, entomologists and producers.  相似文献   

4.
Octodontoidea is the most species-rich clade among hystricomorph rodents, and has a fossil record going back to at least the late Oligocene. Affinities of fossils previous to the late Miocene differentiation of the extant families Abrocomidae, Echimyidae and Octodontidae are controversial, essentially because these fossils may share few apomorphies with modern species. In fact, pre-late Miocene representatives of Abrocomidae had not been recognised until very recently. Here we revise the early Miocene genus Acarechimys, originally assigned to Echimyidae, and alternatively to stem Octodontoidea or to Octodontidae. A systematic and parsimony-based phylogenetic analysis of the species traditionally included in Acarechimys showed that this genus is part of stem Abrocomidae. These results are primarily supported by morphology of the mandible and lower molars. Acarechimys is here restricted to three species, A. minutus, A. pulchellus and Acarechimys pascuali sp. nov., while another species, A. constans, is here transferred to a new abrocomid genus. The remaining species were nested within Octodontidae. According to these results, Abrocomidae might have been as diverse as its sister clade Octodontidae-Echimyidae during the late Oligocene–early Miocene. Extinction of this diversity would have resulted in marked loss of evolutionary history, with extant abrocomids being currently restricted to late-diverged euhypsodont representatives.  相似文献   

5.
Pan paniscus is unique in the group of African apes because of its range south of the Congo River. Examination of the bio-geographical journey of the genus Pan to the species P. paniscus is important when discussing the evolution of African apes. This paper is a review of the paleo-geographic events, the zoogeography, and faunal sorting which influenced P. paniscus divergence from the Proto-pan ancestor within the recent Miocene through Pliocene Epochs, approximately 10–2 MYA. Finally, by elucidating modern day evidence of food plant forms in the southern periphery exploited by P. paniscus in the forest/savanna mosaic habitat, we are able to conclude with those extrinsic events that most influenced the occurrence and distribution of P. paniscus. Electronic Publication  相似文献   

6.
Balaenidae (right whales) are large, critically endangered baleen whales represented by four living species. The evolutionary relationships of balaenids are poorly known, with the number of genera, relationships to fossil taxa, and position within Mysticeti in contention. This study employs a comprehensive set of morphological characters to address aspects of balaenid phylogeny. A sister‐group relationship between neobalaenids and balaenids is strongly supported, although this conflicts with molecular evidence, which may be an artifact of long‐branch attraction (LBA). Monophyly of Balaenidae is supported, and three major clades are recognized: (1) extinct genus Balaenula, (2) extant and extinct species of the genus Eubalaena, and (3) extant and extinct species of the genus Balaena plus the extinct taxon, Balaenella. The relationships of these clades to one another, as well as to the early Miocene stem balaenid, Morenocetus parvus, remain unresolved. Pliocene taxa, Balaenula astensis and Balaenula balaenopsis, form a clade that is the sister group to the Japanese Pliocene Balaenula sp. Eubalaena glacialis and Pliocene Eubalaena belgica, are in an unresolved polytomy with a clade including E. japonica and E. australis. Extant and fossil species of Balaena form a monophyletic group that is sister group to the Dutch Pliocene Balaenella, although phylogenetic relationships within Balaena remain unresolved.  相似文献   

7.
We reassessed the phylogenetic relationships of dasyuromorphians using a large molecular database comprising previously published and new sequences for both nuclear (nDNA) and mitochondrial (mtDNA) genes from the numbat (Myrmecobius fasciatus), most living species of Dasyuridae, and the recently extinct marsupial wolf, Thylacinus cynocephalus. Our molecular tree suggests that Thylacinidae is sister to Myrmecobiidae + Dasyuridae. We show robust support for the dasyurid intrafamilial classification proposed by Krajewski & Westerman as well as for placement of most dasyurid genera, which suggests substantial homoplasy amongst craniodental characters presently used to generate morphology‐based taxonomies. Molecular dating with relaxed molecular clocks suggests that dasyuromorphian cladogenesis began in the Eocene, and that all three dasyuromorphian families originated prior to the end of this epoch. Radiation within Thylacinidae and Dasyuridae had occurred by the middle to late Oligocene, consistent with recognition of primitive thylacinids (e.g. Badjcinus turnbulli) in the later Oligocene and of putative dasyurids (e.g. Barinya wangala) by the early Miocene. We propose that all four extant dasyurid tribes were in existence by the early Miocene and that most modern dasyurid genera/species were established before the later Miocene. This is in marked contrast to the popularly accepted advocation of their origins in the latest Miocene–early Pliocene. © 2015 The Linnean Society of London  相似文献   

8.
9.
We conducted a morphometric study and wall texture analysis on extant and fossil specimens of the planktonic foraminifera Globigerina falconensis plexus. Our global data reveal morphological inconsistencies between fossil and extant populations. Our results are significant as G. falconensis is widely used in palaeoceanographic studies in conjunction with its sister taxon G. bulloides. Morphologically these two species are similar, with the main difference being the distinctive apertural lip present in Gfalconensis. We selected cores covering the entire stratigraphic range of Gfalconensis, from the early Miocene to current day, spanning sites from high latitudes in the North Atlantic Ocean and the southern Indian Ocean to sites in equatorial regions. The morphology found in the modern ocean is not consistent with the Miocene holotype of Globigerina falconensis Blow described from lower Miocene sediments in Venezuela. A more lobate morphology evolved in the late Miocene, thus, a new name is required for this morphotype, coexisting in the modern oceans with Gfalconensis s.s. We thus describe the new morphospecies, Gneofalconensis for the more lobate forms which evolved in the late Miocene and inhabit the modern oceans. Additionally, we report a pseudocancellate wall texture present in the Gfalconensis plexus. We use the molecular sequences from the PR2 database to explore the generic attribution of the Gfalconensis lineage, confirming its close relationship with Gbulloides and its retention in the genus Globigerina.  相似文献   

10.
The dormice (Gliridae) are a family of rodents represented by relatively few extant species, though the family was much more species-rich during the Early Miocene. Intergeneric phylogenetic relationships among glirids in some cases remain unresolved, despite extensive molecular and morphological analyses. Uncertainty is greatest with respect to the relationships among fossil taxa and how extinct lineages are related to modern species. The fossil genus Hypnomys from the Balearic Islands (western Mediterranean Sea) includes the Late Pleistocene–Holocene species Hypnomys morpheus, which has variously been considered a close relative or subgenus of the extant Eliomys. In the present study, we sequenced ancient mitochondrial DNA from Hmorpheus, which suggests a sister relationship with the extant members of Eliomys. In addition, the pairwise sequence variation between Hypnomys and Eliomys is higher than that observed between congeneric glirid species (e.g., many Graphiurus spp.), which allows us to reject the hypothesis that Hypnomys is a subgenus of Eliomys. Our molecular dating analyses suggest that Hypnomys and Eliomys diverged 13.67 million years ago (95% highest posterior density [HPD] = 7.39–20.07). The relatively early split between these genera together with the molar morphology of early representatives of Hypnomys points to a Middle-Late Miocene origin from a continental glirid with a complex molar pattern, such as Vasseuromys or a closely related genus.  相似文献   

11.
12.

Glyptodonts (Xenarthra, Cingulata) are one of the most amazing Cenozoic South American mammals, with some terminal forms reaching ca. two tons. The Paleogene record of glyptodonts is still poorly known, although some of their diversification is observable in Patagonian Argentina. Since the early and middle Miocene (ca. 19–13 Ma), two large clades can be recognized in South America. One probably has a northern origin (Glyptodontinae), while the other one, called the “austral clade”, is interpreted to have had an austral origin, with the oldest records represented by the “Propalaehoplophorinae” from the late early Miocene of Patagonian Argentina. In this scenario, the extra-Patagonian radiations are still poorly known, despite their importance for understanding the late Miocene and Pliocene diversity. Here, we carry out a comprehensive revision of late Miocene (Chasicoan Stage/Age) glyptodonts of central Argentina (Buenos Aires and San Juan provinces). Our results show that, contrary to what is traditionally assumed, it was a period of very low diversity, with only one species recognized in this region, Kelenkura castroi gen et sp. nov. Our phylogenetic analysis shows that this species represents the sister taxon of the remaining species of the “austral clade”, representing the first branch of the extra-Patagonian radiation. Additionally, K. castroi is the first taxon showing a “fully modern” morphology of the caudal tube.

  相似文献   

13.
The ruminants constitute the largest group of ungulates, with >190 species, and its distribution is widespread throughout all continents except Australia and Antarctica. Six families are traditionally recognized within the suborder Ruminantia: Antilocapridae (pronghorns), Bovidae (cattle, sheep, and antelopes), Cervidae (deer), Giraffidae (giraffes and okapis), Moschidae (musk deer), and Tragulidae (chevrotains). The interrelationships of the families have been an area of controversy among morphology, palaeontology, and molecular studies, and almost all possible evolutionary scenarios have been proposed in the literature. We analyzed a large DNA data set (5,322 nucleotides) for 23 species including both mitochondrial (cytochrome b, 12S ribosomal RNA (rRNA), and 16S rRNA) and nuclear (kappa-casein, cytochrome P-450, lactoferrin, and alpha-lactalbumin) markers. Our results show that the family Tragulidae occupies a basal position with respect to all other ruminant families, confirming the traditional view that separates Tragulina and Pecora. Within the pecorans, Antilocapridae and Giraffidae emerge first, and the families Bovidae, Moschidae, and Cervidae are allied, with the unexpected placement of Moschus close to bovids rather than to cervids. We used these molecular results to assess the homoplastic evolution of morphological characters within the Ruminantia. A Bayesian relaxed molecular clock approach based on the continuous autocorrelation of evolutionary rates along branches was applied to estimate the divergence ages between the major clades of ruminants. The evolutionary radiation of Pecora occurred at the Early/Late Oligocene transition, and Pecoran families diversified and dispersed rapidly during the Early and Middle Miocene. We propose a biogeographic scenario to explain the extraordinary expansion of this group during the Cenozoic era.  相似文献   

14.
Evolution of the cytochromeb gene of mammals   总被引:99,自引:0,他引:99  
Summary With the polymerase chain reaction (PCR) and versatile primers that amplify the whole cytochromeb gene (∼ 1140 bp), we obtained 17 complete gene sequences representing three orders of hoofed mammals (ungulates) and dolphins (cetaceans). The fossil record of some ungulate lineages allowed estimation of the evolutionary rates for various components of the cytochromeb DNA and amino acid sequences. The relative rates of substitution at first, second, and third positions within codons are in the ratio 10 to 1 to at least 33. For deep divergences (>5 million years) it appears that both replacements and silent transversions in this mitochondrial gene can be used for phylogenetic inference. Phylogenetic findings include the association of (1) cetaceans, artiodactyls, and perissodactyls to the exclusion of elephants and humans, (2) pronghorn and fallow deer to the exclusion of bovids (i. e., cow, sheep, and goat), (3) sheep and goat to the exclusion of other pecorans (i. e., cow, giraffe, deer, and pronghorn), and (4) advanced ruminants to the exclusion of the chevrotain and other artiodactyls. Comparisons of these cytochromeb sequences support current structure-function models for this membrane-spanning protein. That part of the outer surface which includes the Qo redox center is more constrained than the remainder of the molecule, namely, the transmembrane segments and the surface that protrudes into the mitochondrial matrix. Many of the amino acid replacements within the transmembrane segments are exchanges between hydrophobic residues (especially leucine, isoleucine, and valine). Replacement changes at first and second positions of codons approximate a negative binomial distribution, similar to other protein-coding sequences. At four-fold degenerate positions of codons, the nucleotide substitutions approximate a Poisson distribution, implying that the underlying mutational spectrum is random with respect to position.  相似文献   

15.
Rhinos are the only modern perissodactyls that possess cranial weapons similar to the horns, antlers and ossicones of modern ruminants. Yet, unlike ruminants, there is no clear relationship between sexual dimorphism and sociality. It is possible to extend the study of the coevolution of sociality and sexual dimorphism into extinct rhinos by examining the demographic patterns in large fossil assemblages. An assemblage of the North American early Miocene (∼22 million years ago) rhino, Menoceras arikarense, from Agate Springs National Monument, Nebraska, exhibits dimorphism in incisor size and nasal bone size, but there is no detectible dimorphism in body size. The degree of dimorphism of the nasal horn is greater than the degree of sexual dimorphism of any living rhino and more like that of modern horned ruminants. The greater degree of sexual dimorphism in Menoceras horns may relate to its relatively small body size and suggests that the horn had a more sex-specific function. It could be hypothesized that Menoceras evolved a more gregarious type of sociality in which a fewer number of males were capable of monopolizing a larger number of females. Demographic patterns in the Menoceras assemblage indicate that males suffered from a localized risk of elevated mortality at an age equivalent to the years of early adulthood. This mortality pattern is typical of living rhinos and indicates that young males were susceptible to the aggressive behaviors of dominant individuals in areas conducive to fossilization (e.g., ponds, lakes, rivers). Menoceras mortality patterns do not suggest a type of sociality different from modern rhinos although a group forming type of sociality remains possible. Among both living and extinct rhinos, the severity of socially mediated mortality seems unrelated to the degree of sexual dimorphism. Thus, sexual dimorphism in rhinos is not consistent with traditional theories about the co-evolution of sexual dimorphism and sociality.  相似文献   

16.
In Europe, Miocene rails (Aves, Rallidae) are quite abundant, but their phylogenetic placement in the context of recent forms has remained elusive. Rails from the early Miocene of the Saint‐Gérand‐le‐Puy area in central France were first described in the 19th century, and currently, only two species are recognized, namely Palaeoaramides christyi and Paraortygometra porzanoides. Our examination of the material however suggests the presence of four, likely coeval, species of rail from these deposits. Palaeoaramides eximius, previously synonymized with Palaeoaramides christyi, is here shown to probably be a distinct species, and a previously unrecognized rail, Baselrallus intermedius gen. et sp. nov., is described. To find out how these fossil rails are related to modern Rallidae, we compared them with an extensive sample of extant rails and identified plesiomorphic and derived features for crown group Rallidae. Our assessment does not support a particularly close relationship of either Palaeoaramides to Aramides or Paraortygometra to Crex (Ortygometra), and overall, these fossil rails are more primitive than previously assumed. Based on our observations of the morphology of the previously undescribed humerus of Palaeoaramides, we show this taxon to be outside crown group Rallidae, and perhaps closely related to the early Oligocene taxon Belgirallus. On the other hand, Paraortygometra porzanoides bears a resemblance to recent flufftails (Sarothrura spp.) in some elements, but whether it can be included in a clade together with flufftails is uncertain.  相似文献   

17.
The oldest ape     
This paper recounts the history and significance of Morotopithecus bishopi, an early Miocene East African ape. Morotopithecus differs in intriguing ways from its contemporary Proconsul. While craniodental differences are slight, the known elements of its postcranium suggest that Morotopithecus was capable of modern ape–like positional behaviors, including vertical postures, deliberate climbing, and arm hanging. In contrast, Proconsul and other early and middle Miocene hominoids have been reconstructed as above–branch quadrupeds. Paleoanthropologists are currently divided over whether and which of the anatomical features associated with upright posture and suspension in the modern apes are due to inheritance or independent evolution. This debate has important implications for interpreting the phylogenetic positions of both Morotopithecus and Proconsul, as well as for reconstructing the pattern and timing of the emergence of modern ape adaptations.  相似文献   

18.
The aim of this paper is to survey the economic approach in relation to animal use during Upper Palaeolithic times in Northern Spain. The animals present in the archaeological record can be separated into main groups, like those present by natural reasons and those introduced by human groups. Also in the anthropic aported animals, some of them are related to food procurements and others to economic reasons. Animals like deer, bovids, equids and so on, were mainly related to nutrition, while some others like mustelids, canids or felines were more related to the obtention of furs or other non-alimentary uses. The analysis of the “main-six” (red deer, roe deer, big bovids, horse, ibex and wild boar) showed that all of them were used throughout the Upper Palaeolithic without many changes in time.  相似文献   

19.
DNA phylogenies have gradually shed light on the phylogenetic relationships of the large babbler group. We focus in this study on the family Leiothrichidae (laughingthrushes and “song babblers”), which represents the largest clade of babblers in terms of species diversity. Our phylogeny includes all genera and 82% of the recognized species, using mitochondrial and nuclear loci. The sister group to Leiothrichidae is composed of the Pellorneidae (“jungle babblers”) plus the genus Alcippe. Within Leiothrichidae, four strongly supported primary clades (A–D) are recovered. Clade A includes Grammatoptila, Laniellus and Cutia. Clade B includes a large group of laughingthrushes, all of them classified in Trochalopteron. In Clade C, the two laughingthrushes endemic to southern India, T. fairbanki and T. cachinnans, which have recently been proposed to be placed in the newly erected genus Montecincla, form a sister clade to the group comprising the “song babblers” (Lioptila, Leiothrix, Heterophasia, Minla, Liocichla, Actinodura, Chrysominla, Siva, and Sibia). Clade D includes the African babblers (Turdoides, Phyllanthus, Kupeornis), Asian relatives (Argya, Acanthoptila, Chatarrhaea) and all remaining laughingthrushes (Garrulax). The time estimates suggest that the early diversification of the Leiothrichidae occurred in the mid‐Miocene, a period that corresponds to the diversification of many passerine groups in Asia. A revised taxonomic classification of the family is proposed in the light of these results.  相似文献   

20.
This study presents the new fossil material of bovids from the recently discovered upper Miocene locality of Platania, Drama (Greece). The material was excavated from 2012 to 2016 and yielded approximately 760 specimens attributed to hipparions, rhinos, cervids, giraffids, suids, proboscideans, hyaenids, and turtles. The bovid material described here includes six taxa of Antilopinae and one of Bovinae. Antilopines are represented by Gazella sp., Gazella cf. ancyrensis, Prostrepsiceros aff. syridisi, cf. Palaeoreas, Palaeoryx minor nov. sp., and Tragoreas? aff. oryxoides. Bovines are recorded by a single boselaphine attributed to Miotragocerus sp. Departing from other Palaeoryx species, the new species P. minor has rather straight and weakly divergent horn-cores tilted backwards, obtuse facial and occipito-parietal angles, and smaller cranial and horn-core size, though associated with a proportionally large toothrow. Miotragocerus sp. from Platania seems to be conspecific to the Miotragocerus sp. from the end-Vallesian Nikiti-1 fauna (Greece). The bovid assemblage of Platania shows a mix of both Vallesian and Turolian taxa indicating a likely late Vallesian-early Turolian age.  相似文献   

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