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In the creationist field of baraminology, one strategy for understanding relationships between creatures is to identify an apobaramin. An apobaramin is a group of organisms that are very distinct from all other organisms, such as chiropterans (bats) which are the only mammals capable of powered flight. In this two-part series we are proposing that ruminants form a clear apobaramin based on both molecular (part 1) and morphologic (here in part 2) characteristics. Many of the unique features of the ruminant stomach are discussed. Osseous headgear is also discussed, as well as its apparent loss from some ruminant families. Further important research necessary to determine if ruminants comprise a single or multiple created kinds is briefly outlined. Ruminants clearly reflect the glory of their Creator, who is all wise and provides for His creatures. [ABSTRACT FROM AUTHOR]

Ceratogaulus, a member of the extinct fossorial rodent clade Mylagaulidae, is the only known rodent with horns and the smallest known horned mammal. The function of the large, dorsally projecting nasal horns on this burrowing animal has been the subject of wide speculation among palaeontologists; suggested uses range from sexual combat to burrowing. Mammals have evolved adaptations for digging repeatedly; horns and other cranial appendages have also evolved numerous times. These two adaptations co-occur in mammals extremely rarely: only two fossil genera (Ceratogaulus and the xenarthran Peltephilus) and no extant mammals are both horned and fossorial. Tracing the evolution of fossoriality in aplodontoid rodents (the larger clade to which Ceratogaulus belongs) reveals that Ceratogaulus descended from ancestors who dug by head-lifting. Whereas this suggests an obvious explanation for the horns of this rodent, evidence from functional morphology, anatomy, phylogeny and geologic context indicates that the horns in Ceratogaulus were used for defence, rather than digging, and evolved to offset increased predation costs associated with spending more time foraging above ground as body size increased.

Abstract Morphological disparity arises through changes in the ontogeny of structures; however, a major challenge of studying the effect of development on shape is the difficulty of collecting time series of data for large numbers of taxa. A proxy for developmental series proposed here is the age at sexual maturity, a developmental milestone potentially tied to the development of structures with documented use in intrasexual competition, such as cranial appendages in Artiodactyla. This study tested the hypothesis that ruminant cranial appendage shape and size correlate with onset of sexual maturity, predicting that late sexual maturity would correlate with larger, more complicated cranial appendages. Published data for cranial appendage shape and size in extant taxa were tested for correlations with sexual maturity using linear mixed‐effect models and phylogenetic generalized least‐squares analyses. Ancestral state reconstructions were used to assess correlated variables for developmental shifts indicative of heterochrony. These tests showed that phylogeny and body mass were the most common predictors of cranial appendage shape and sexual maturity was only significant as an interaction with body mass. Nevertheless, using developmental milestones as proxies for ontogeny may still be valuable in targeting future research to better understand the role of development in the evolution of disparate morphology when correlations exist between the milestone and shape.

Morphological disparity arises through changes in the ontogeny of structures; however, a major challenge of studying the effect of development on shape is the difficulty of collecting time series of data for large numbers of taxa. A proxy for developmental series proposed here is the age at sexual maturity, a developmental milestone potentially tied to the development of structures with documented use in intrasexual competition, such as cranial appendages in Artiodactyla. This study tested the hypothesis that ruminant cranial appendage shape and size correlate with onset of sexual maturity, predicting that late sexual maturity would correlate with larger, more complicated cranial appendages. Published data for cranial appendage shape and size in extant taxa were tested for correlations with sexual maturity using linear mixed-effect models and phylogenetic generalized least-squares analyses. Ancestral state reconstructions were used to assess correlated variables for developmental shifts indicative of heterochrony. These tests showed that phylogeny and body mass were the most common predictors of cranial appendage shape and sexual maturity was only significant as an interaction with body mass. Nevertheless, using developmental milestones as proxies for ontogeny may still be valuable in targeting future research to better understand the role of development in the evolution of disparate morphology when correlations exist between the milestone and shape. [ABSTRACT FROM AUTHOR]

We describe a new species of Prolibytherium, P. fusus, sp. nov., from the lower Miocene of Pakistan, thus extending the genus to Asia. Prolibytherium is otherwise known only from Libya. This species differs from Prolibytherium magnieri in several basioccipital and atlanto-occipital morphologies. Namely, the posterior basioccipital tuberosities are continuous at the midline and lack the elevated transverse ridge seen in P. magnieri, and the notch formed between the lateral occipital condyles and paraoccipital process is lower. Both species of Prolibytherium have a characteristic ventrally fused occipital condyle at the midline, with a notably fuller circumferential articular surface. Prolibytherium magnieri also has thickened dorsal and ventral arches of the atlas. These specimens also possess a longitudinal groove for the Eustachian tube extending from the alisphenoid canal to the bullae, and a second deep grove isolating the basisphenoid bone from the temporal bone. These, plus several other atlanto-occipital morphologies strengthen the cervical support of the head. This is especially important for Prolibytherium, as the taxon possesses massive aliform cranial appendages. We relate the approximation of the occipital condyles to a convergent state in two giraffids ( Giraffokeryx punjabiensis and Schansitherium tafeli), each of which possesses multiple pairs of ossicones, presumably necessitating a strengthened atlanto-occipital joint. [ABSTRACT FROM AUTHOR]

Key innovations are newly acquired structures that permit the performance of a new function and open new adaptive zones, and are, therefore, of paramount significance for understanding the history of the Ruminantia, particularly its diversification through the Miocene. Here we review and discuss what is known about these evolutionary novelties, with special emphasis on the appearance and evolution of cranial appendages and high-crowned (or hypsodont) teeth. Cranial appendages probably favored the diversification of pecorans by being structures strongly related to sexual selection, whereas the acquisition of hypsodont teeth could have expanded potential dietary breadth and allowed species to extend diets into the grazing range without eliminating browsing as a potential diet. When analyzed in conjunction with patterns of faunal diversity and in the context of climatic changes, it seems that the overall view that ruminant cranial appendages and hypsodonty may have started responding to increased patterns of seasonality and the opening-up of ecosystems is roughly valid. Instead, they occurred through several distinct pulses and varied widely among continents. This review is, to our knowledge, the first to highlight that the evolution of these innovations has been far from constant and uniform through time. Furthermore, we identify that both a first attempt to increase hypsodonty starting in the early Miocene and a first evolution of antlers and pronghorns were interrupted as a consequence of wide climatic fluctuations in the early-middle Miocene transition. [ABSTRACT FROM AUTHOR]

Dental and cranial appendage remains of Cervidae from the fossil site of Dorn-Dürkheim are studied in detail. The material mainly includes isolated teeth, isolated pedicles and antler pieces. Neither tooth rows nor complete appendages are recorded. Comparative morphology and statistics of morphometrics (principal component analysis and discriminant analysis) allow for the classification of small and large dentitions, small cranial appendages, two morphotypes of large pedicles and two morphotypes of large antlers. Possible combinations of the classified units document the sympatric occurrence of three species, namely, Procapreolus sp., Muntiacinae gen. and sp. indet., cf. Cervavitulus mimus, but the fragmentary condition of the material leads to ambiguity regarding their composition and, consequently, to a certain extent regarding the taxonomic identification. However, these remains indicate the contemporaneous occurrence of early Turolian members of the crown cervids Muntiacinae and Capreolinae and close a previous spatiotemporal gap in the European cervid record. In addition, their presence proves the progressive turnover from dichotomous-antlered muntiacines to early monopodial-antlered crown cervids from NE to SW Europe in the late Miocene. The taxonomical assignment challenges the recent hypothesis on the origin of crown Cervidae around the middle/late Miocene border since Dorn-Dürkheim cervids provide further evidence for the successive achievement of derived characters in cranial appendages of crown cervids (mediopostorbital position and backwards orientation of pedicles, coronet development, shaft development/elongation, beam development and increase in number of antler tines) in the lineage of crown cervids, which originated during the middle Miocene. [ABSTRACT FROM AUTHOR]

Horns are cranial appendages, which are unique in ruminants. Cattle (Bos taurus) and sheep (Ovis aries) cranial appendages exhibit various forms of morphology, including wild-type two-horn phenotype, polled phenotype and scur phenotype. These animals provide an ideal model for studies on the underlying relationship between quality and quantitative traits of cattle and sheep horn and the molecular mechanisms of horn phenotype as a polygenic regulation for quality traits. In recent years, some research progresses of cattle and sheep horns are successively reported, which helps us better understand the evolutionary origin of new organ, the effects of natural selection, sex selection and artificial selection on horn phenotypes. In this review, we introduce in details the recent advances on the research of horn traits in cattle and sheep, and summarize the genetic mapping of multi-horned phenotypes, the genetic mapping of polled locus, and studies on scur phenotype. Moreover, we discuss potential problems in such research, thereby providing a reference for investigation on the genetic mechanisms of horn traits in ruminants.

Antlers are bony appendages of deer that undergo periodic regeneration from the top of permanent outgrowths (the pedicles) of the frontal bones. Of the "less familiar" bone types whose study was advocated by John Currey to gain a better understanding of structure-function relationships of mineralized tissues and organs, antlers were of special interest to him. The present review summarizes our current knowledge about the evolution, development, structure, mineralization, and biomechanics of antlers and how their formation is affected by environmental factors like nutrition. Furthermore, the potential role of antlers as a model in bone biology and several fields of biomedicine as well as their use as a monitoring tool in environmental studies are discussed. • Antlers are deciduous cranial bony appendages in Cervidae that, except for reindeer, constitute male secondary sex characteristics. • Antlers develop from permanent pedicles, whose growth is dependent on a specialized (antlerogenic) periosteum. • Antlers are the fastest growing bones and are formed by endochondral and perichondral/intramembranous ossification. • Antlers are used for inter-male fighting during the rut and their biomechanical properties are adapted to that role. • Antlers are a model for studying bone growth and mineralization as well as epimorphic regeneration. [ABSTRACT FROM AUTHOR]