Evolution of ruminant headgear: a review

The horns, ossicones and antlers of ruminants are familiar and diverse examples of cranial appendages. We collectively term ruminant cranial appendages 'headgear'; this includes four extant forms: antlers (in cervids), horns (in bovids), pronghorns (in pronghorn antelope) and ossicones (in giraffids). Headgear evolution remains an open and intriguing question because phylogenies (molecular and morphological), adult headgear structure and headgear development (where data are available) all suggest different pictures of ruminant evolution. We discuss what is known about the evolution of headgear, including the evidence motivating previous hypotheses of single versus multiple origins, and the implications of recent phylogenetic revisions for these hypotheses. Inclusion of developmental data is critical for progress on the question of headgear evolution, and we synthesize the scattered literature on this front. The areas most in need of attention are early development in general; pronghorn and ossicone development in particular; and histological study of fossil forms of headgear. An integrative study of headgear development and evolution may have ramifications beyond the fields of systematics and evolution. Researchers in organismal biology, as well as those in biomedical fields investigating skin, bone and regenerative medicine, may all benefit from insights produced by this line of research.     

The Miocene differentiation of old world Pecora (Mammalia)

Dental and horn core/antler morphology is discussed for some representative lower and middle Miocene pecorans in a review of the phylogeny and early zoogeography of the modern Old World families. Giraffes and bovids are more closely related than either is to deer. Andegameryx, Walangania and Teruelia are related to giraffoids plus bovoids together; Amphimoschus and Hispanomeryx are a probable sister group of bovoids; Propalaeoryx is the sister group of the giraffids plus climacoceratids. Procervulus and Lagomeryx may be closer to modern deer than are Stephanocemas and Dicrocerus but all are included in the Cervidae. The horn structure of Palaeomeryx has resemblances to giraffids, but its teeth and postcranial bones are more like cervids and it is placed in the Cervoidea. Pecorans seem to have evolved in Eurasia and there gave rise to deer. By the early Miocene some pecorans had entered Arabo‐Africa where they gave rise to giraffids and probably bovids. The relationships and zoogeography of the early bovids Eotragus, Homoiodorcas and Caprotragoides are likely to be important for later bovid history.     

甘肃临夏盆地首次发现乌米兽(牛科,偶蹄类)头骨化石（英文）

报道并描述了一件来自甘肃临夏盆地的中间乌米兽(Urmiatherium intermedium)头骨化石新材料,该材料产自柳树组上部,属于晚中新世晚期杨家山动物群。中间乌米兽是一种大型的晚中新世牛科动物,角心特化,短且呈薄板状,并且在基部相互靠近。在角心前后方的额骨和顶骨上,发育大片赘生骨疣,这些骨疣与角心一起,合称角器。20世纪初,步林报道了中国北方晚中新世地层中的大量中间乌米兽化石,包括产自山西保德和甘肃庆阳的20多件头骨以及很多破碎的齿列和骨骼。本文报道的乌米兽头骨化石是乌米兽在甘肃临夏盆地的首次发现,将其在中国北方的分布向西扩展到了青藏高原东北缘地带。乌米兽被普遍认为与近旋角羊(Plesiaddax)、和政羊(Hezhengia)和柴达木兽(Tsaidamotherium)等晚中新世"麝牛类"牛科动物具有较近的亲缘关系,但其系统发育地位仍存有争议。相比其他晚中新世"麝牛类"牛科动物,乌米兽的分布较广,从伊朗至中国北方都有分布,但它鲜与其他晚中新世"麝牛类"牛科动物伴生。在临夏盆地,与其伴生的牛科动物目前仅发现中华羚(Sinotragus)一种。     

New data on late Miocene mammals of Kohfidisch, Austria

Cervids and bovids of the Early Turolian mammalian fauna of Kohfidisch (Austria) are reviewed. A new species, Micromeryx mirus sp. nov. (Moschidae) is described.     

Prostrepsiceros and Protragelaphus (Artiodactyla,Mammalia) from the Late Miocene locality of Chomateri (Attica,Greece)

The Late Miocene fossiliferous locality of Chomateri is located close to the classic locality of Pikermi, but unfortunately its faunal context is not sufficiently known. Some fossil remains of spiral-horned antelopes from Chomateri are assigned to Prostrepsiceros rotundicornis and Protragelaphus skouzesi. The co-existence of P. rotundicornis and P. skouzesi is relatively rare in the Late Miocene, but well-documented in Pikermi. Comparisons of the Chomateri material support a middle Turolian age for the Chomateri locality and suggest a close chronological relation to the Pikermi fauna.     

A new Middle Miocene mammalian fauna from Mordoğan (Western Turkey)

Ardiç-Mordo?an is a new fossil Mammal locality in the Karaburun Peninsula of Western Turkey. Among its fauna, which is described here, the carnivores are especially interesting, with the most complete specimens ever found ofPercrocuta miocenica and of a primitive species of hyaenid, of which a new subspecies is described,Protictitherium intermedium paralium. This fauna is strongly reminiscent of those of sever-al other Middle Miocene localities in this area, Çandir, Pa?alar and Inönü in Turkey, and Prebreza in Serbia, and they must all belong to the same mammalian zone. Their ungulates attest an open environment which must have been widespread in the Turko-Balkanic area in Serravallian times.     

中国新近纪牛科分类及演化规律

我国新近纪的牛科相当繁盛。至今已记录了30属,归入5个亚科(Hypsodontinae,Urmiatheriinae,Caprinae,Antilopinae和Bovinae)。化石主要出现在我国北方且大部分为土著类型,以颊齿中等高冠至高冠、前臼齿列短、头骨粗壮、弯曲和角心特化为特征。在整个新近纪时期,牛科经历了5个发展阶段和4次大的更替。与同时代欧亚大陆其他地区的牛科类群相比,中国牛科化石出现的时间早,且基本组成不同。在中新世,我国的牛科主要由Hypsodontinae,Urmiatheriinae,Caprinae的早期特化类型和Gazella组成,Boselaphini稀少并缺乏转角羚羊(Antilopinae);在上新世,除Gazella外,我国北方仍生活着Caprinae的一组土著类型。     

Molecular phylogeny of musk deer: a genomic view with mitochondrial 16S rRNA and cytochrome b gene

The phylogenetic status of the infra order Pecora is controversial, even though it is supported by paleontological, morphological, and molecular evidence. We analyzed two mitochondrial genes (i.e., 16S rRNA and cytochrome b) to resolve the phylogenetic position of pecoran species, i.e., the Bovidae, Cervidae, and Moschidae endemic to the Indian subcontinent. We used phylogenetic analysis based on different algorithms, including neighbor joining, maximum parsimony, Bayesian inference, maximum likelihood, minimum evolution, median joining network, along with multidimensional scaling, and DNA word analysis. Our results established the basal position of Tragulidae and the monophyly of the infra order Pecora within the Suborder Ruminantia. Our results also demonstrated that Bovidae, Cervidae, and Moschidae are allied with the placement of musk deer as more closely related to bovids than to cervids. Molecular dating based on sequence analysis shows that the radiation of Pecora occurred during the early Oligocene and that the majority of the pecoran families radiated and dispersed rapidly during the Oligocene/Miocene transition.     

Molecular phylogeny of caprines (Bovidae, Antilopinae): the question of their origin and diversification during the Miocene

Caprines include all bovids related to sheep and goat. The composition of the group is controversial and inter-generic relationships have been widely debated. Here, we analysed 2469 characters draw from three distinct molecular markers, i.e. two mitochondrial genes (cytochrome b and 12S rRNA) and one nuclear fragment (exon 4 of the κ -casein gene). The taxonomic sampling includes all genera putatively described as caprines, as well as several other bovid genera in order to elucidate the position of caprines within the family Bovidae, and to determine the exact composition of the group. Phylogenetic analyses confirm firstly that Pseudoryx and Saiga do not belong to caprines, and secondly, that all tribes classically defined in the literature are not monophyletic, supporting the inclusion of all caprine species into a unique enlarged tribe Caprini sensu lato . Our results are in contradiction with previous investigations suggesting a sister-group relationship between Ovis (sheep and mouflons) and Budorcas (takins). By using a molecular calibration point at 18.5 Mya for the first appearance of bovids, we estimated divergence times with our molecular data. We also performed biogeographic inferences to better understand the origin and diversification of caprines during the Neogene. Our analyses suggest that caprines shared a common ancestor with Alcelaphini and Hippotragini in the middle-late Miocene (13.37 ± 0.70 Mya). Our results also indicate that the extant generic diversity of caprines resulted from a rapid adaptive radiation during the late Miocene, at 10.96 ± 0.73 Mya. We propose that this adaptive radiation resulted from the acquisition of reduced metacarpals, a key innovation which occurred during the late Miocene as a consequence of insularity isolation in the mountainous mega-archipelago between Mediterranean and Paratethys Seas.     

Palaeoreas,Majoreas, and Stryfnotherium gen. nov. (Mammalia: Artiodactyla: Bovidae) from the Late Miocene of Greece

A new comparative study of the two crania, LGPUT RZO-03 and LGPUT RZO-68 attributed to Palaeoreas zouavei Bouvrain, 1980 from the Late Miocene of Axios Valley, Greece reveals great morphological and metric differences between them, which require the exclusion of LGPUT RZO-68 from this species and even from Palaeoreas Gaudry, 1861. This decision leaves unsupported many diagnostic features of P. zouavei applied by previous authors and along with recent data from Bulgaria put in doubt the validity of P. zouavei as a whole. As a result, the genus Palaeoreas is re-defined as monotypic and the cranial morphometric changes of P. lindermayeri (Wagner, 1848) are discussed on a temporal basis. An updated taxonomic analysis confirms the presence of P. lindermayeri in the Late Turolian mammal assemblage of Dytiko-1 (Axios Valley, Greece) but rejects its occurrence at Dytiko-2. Instead, a re-examination of old cranial specimens and a study of new ones suggest the presence in both sites of Majoreas Kostopoulos, 2004 a Late Miocene taxon previously mostly known from the eastern banks of the Aegean Sea. A reassessment of the LGPUT RZO-68 cranium, and its comparison with Palaeoreas and Criotherium Forsyth-Major, 1891, suggests that it deserves taxonomic distinction at genus and species levels: Stryfnotherium exophthalmon.     

Zhailimeryx, A New Lophiomerycid Artiodactyl (Mammalia) from the Late Middle Eocene of Central China and the Early Evolution of Ruminants

A new genus and species of primitive selenodont artiodactyl, Zhailimeryx jingweni, occurs in the late middle Eocene Zhaili Member of the Heti Formation, Yuanqu Basin, Shanxi Province, China. A phylogenetic analysis of dental characters suggests that Zhailimeryx is closely related to Lophiomeryx and other lophiomerycid ruminants of Asia and Europe. Zhailimeryx and other Eocene records of Lophiomerycidae from Asia support an Asian origin for this family, followed by dispersal into Europe both before and after the Grande Coupure. Morphological evidence from Zhailimeryx suggests that ruminant artiodactyls had already undergone substantial diversification prior to the late middle Eocene, and it reopens the issue of whether the higher taxa Tragulina and Pecora are valid expressions of ruminant phylogeny.     

Genomic variation in the mitochondrially encoded cytochrome b (MT-CYB) and 16S rRNA (MT-RNR2) genes: characterization of eight endangered Pecoran species

In an effort to develop species-specific identification markers, we examined genetic variants and molecular signatures within genes encoding mitochondrial cytochrome b and 16S rRNA in eight endangered Pecoran species endemic to the Indian peninsula. Our results revealed that the cytochrome b gene exhibited higher sequence diversity than the 16S rRNA gene, both between and within species. However, the 16S rRNA gene harboured a larger number of species-specific mutation sites compared with the cytochrome b gene, suggesting that it could be useful for species identification. Indeed, we successfully used 'forensically informative nucleotide sequencing' (FINS) analysis of the 16S rRNA gene to identify two previously unknown biological specimens.     

Analysis of bovidae genomes: Arrangement of repeated and single copy DNA sequences in bovine,goat and sheep

Approximately 43–60% of the total genome in bovine, goat and sheep consisted of interspersed repeated and single copy DNA sequences. Most of the interspersed repeated DNA sequences were 1500–2400 nucleotide pair long while a minor portion was more than 4000 nucleotide pair long in goat and sheep and 3200 nucleotide pair long in bovine. About 1/3rd of single copy sequence were interspersed and their length was in the range of 1000–1500 nucleotide pairs.