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Craniovascular traits in the endocranium (traces of middle meningeal vessels and dural venous sinuses, emissary foramina) provide evidence of vascular anatomy in osteological samples. We investigate the craniovascular variation in four South American samples and the effect of artificial cranial modifications (ACM). CT scans of human adult crania from four archeological samples from southern South America (including skulls with ACM) are used for the analyses. The craniovascular features in the four samples are described, skulls with and without ACM are compared, and additionally, South Americans are compared to a previously analyzed sample of Europeans. Of the four South American samples, the Southern Patagonian differs the most, showing the most distinct cranial dimensions, no ACM, and larger diameters of the emissary foramina. Unlike previous studies, we did not find any major differences in craniovascular features between modified and non-modified skulls, except that the skulls with ACM present somewhat smaller foramina. South Americans significantly differed from Europeans, especially in the anteroposterior dominance of the middle meningeal artery, in the pattern of sinus confluence, in the occurrence of enlarged occipito-marginal sinuses, and in foramina frequencies and diameters. Craniovascular morphology is not affected by the cranial size, even in skulls with ACM, indicating a minor or null influence of structural topological factors. Concerning the samples from distinct geographic and climatic environments, it must be evaluated whether the craniovascular morphogenesis might be partially influenced by specific functions possibly associated with thermoregulation, intracranial pressure, and the maintenance of intracranial homeostasis.

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OBJECTIVES: Craniofacial morphology (CFM) is often used to address questions about the biological affinities of the earliest Americans, or Paleoindians, but resolution is complicated in part by a lack of well-preserved crania. The Wilson-Leonard 2 (WL-2) Paleoindian skull from Texas has never been fully analyzed because it is crushed and cannot be physically reconstructed. This study employs a digital restoration for comprehensive assessment and analysis of WL-2. MATERIALS AND METHODS: High-resolution CT data and geometric morphometrics are used to restore the WL-2 skull and analyze its morphology using 65 craniometric measurements acquired on the restoration. These data allow for a full morphological description and multivariate (Mahalanobis Distance and Principal Component) comparisons to other Paleoindians and recent populations. RESULTS: WL-2 has a long, narrow braincase, and a short, modestly prognathic face. Compared with other Paleoindians, she is individually similar to several skulls from Brazil, but aligns most closely with pooled samples from the US and Mexico. WL-2 is most similar to recent populations from Europe, Asia, and the Americas, and markedly different to those from Africa and Australia. DISCUSSION: The overall morphology of WL-2 and her association with Asians and Europeans align well with trends identified in other CFM analyses. Her affinity to recent Amerindians contrasts with the findings of many previous CFM studies, but is seemingly consistent with molecular analyses suggesting a close relationship between some Paleoindians and modern American Indians. This study demonstrates the potential for using digital anthropological methods to study other Paleoindian crania whose data value is limited by physical destruction and/or deformation.

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The external morphology, internal oral morphology, the chondrocranium and the hyobranchial apparatus of Elachistocleis bumbameuboi, E. cf. piauiensis, E. cesarii and E. bicolor are described and compared with each other and with other species of microhylids using available descriptions from the literature. The general morphology of Elachistocleis species is conservative in many aspects. Differences between species are subtle and are found in the body shape, the edge of the snout, fin height, if the lateral line is evident, the presence of regular pustules in the buccal roof arena, the posterolateral edge of the cartilago suprarostralis, the shape of the fenestra in the occipital region, presence or absence of fenestra hypophysea, the margin of the processus antorbitalis, expansions in the ventrolateral process, the shape and inclination of the fenestra subocularis, whether the subotic process is single or slightly bifid, and the inclination of the processus anterolateralis hyalis.

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This broad literature review considers advances in the study of cranial vault modification with an emphasis on investigations of Andean skeletal remains over the last two decades. I delimit three broad categories of research, building on Verano's synthesis of the state of Andean paleopathology in 1997. These are associations with skeletal pathological conditions, classification and morphology, and social identity. Progress is noted in each of these areas with a particular emphasis on methodological advances in studying morphology as well as the growth of contextualized bioarchaeology and the incorporation of social theory in the consideration of cranial modification as a cultural practice. The article concludes with avenues for future research on head shaping in the Andes specifically and paleopathology more broadly.

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Abstract Fish-eating in bats evolved independently in Myotis vivesi (Vespertillionidae) and Noctilio leporinus (Noctilionidae). We compared cranial morphological characters and bite force between these species to test the existence of evolutionary parallelism in piscivory. We collected cranial distances of M. vivesi, two related insectivorous bats (M. velifer and M. keaysi), two facultatively piscivorous bats (M. daubentonii and M. capaccinii), and N. leporinus. We analyzed morphometric data applying multivariate methods to test for differences among the six species. We also measured bite force in M. vivesi and evaluated if this value was well predicted by its cranial size. Both piscivorous species were morphologically different from the facultatively piscivorous and insectivorous species, and skull size had a significant contribution to this difference. However, we did not find morphological and functional similarities that could be interpreted as parallelisms between M. vivesi and N. leporinus. These two piscivorous species differed significantly in cranial measurements and in bite force. Bite force measured for M. vivesi was well predicted by skull size. Piscivory in M. vivesi might be associated to the existence of a vertically displaced temporal muscle and an increase in gape angle that allows a moderate bite force to process food.(AU)

Resumen La alimentación por peces en murciélagos evolucionó independientemente en Myotis vivesi (Vespertilionidae) y Noctilio leporinus (Phyllostomidae). En este estudio se compararon características craneales morfológicas y fuerza de mordida entre estas especies, para probar la existencia de paralelismo evolucionario en piscivoría. Se recolectaron distancias craneales en M. vivesi, dos parientes insectívoros (M. velifer y M. keaysi), dos murciélagos piscívoros facultativos (M. daubentonii y M. capaccinii), y N. leporinus. Se analizaron datos morfométricos aplicando múltiples métodos para probar las diferencias entre las seis especies. Se midió la fuerza de mordida en M. vivesi y se evalúo si puede ser predicha por el tamaño del cráneo. Las especies piscívoras fueron morfológicamente diferentes de las facultativamente piscívoras y las insectívoras, el tamaño del cráneo tuvo una contribución significativa en esta diferencia. Sin embargo, no encontramos semejanzas morfológicas y funcionales que puedan ser interpretadas como paralelismos entre M. vivesi y N. leporinus. Estas dos especies piscívoras difieren significativamente en medidas craneales y fuerza de mordida. La fuerza de mordida en M. vivesi fue efectivamente predicha por el tamaño de cráneo. La piscivoría en M. vivesi puede estar asociada con la existencia de un músculo temporal verticalmente desplazado y el incremento en el ángulo de apertura mandibular que permite moderar la fuerza de mordida para procesar el alimento.(AU)

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This study aimed to examine the relationship between skull size and the level of cranial vault suture closure. A total of 50 Myrmecophaga tridactyla Linnaeus, 1758 and 178 Tamandua tetradactyla Linnaeus, 1758 skulls were analyzed in relation to 18 skull dimensions. The skulls were grouped into three levels of suture closure: no sutures closed (level 0), one or all the fallowing sutures closed: interfrontalis, sagitalis and coronalis (level 1) and all sutures closed (level 2). The results indicated that among the 18 variables measured, 17 showed significant differences (p ≤ 0.01) between level 0 and level 1 skulls of T. tetradactyla; as well as between level 0 and level 1, and level 0 and level 2 skulls of M. tridactyla. M. tridactyla level 1 and level 2 had no significant difference among any of the 18 dimensions. The foramen magnum height in both species showed no significant difference (p > 0.05) among any suture categories. In principle, suture closure level and cranial dimensions are related. The specimens with larger cranial dimensions showed greater number of cranial vault sutures closed for both species of anteaters. Tamandua tetradactyla and M. tridactyla specimens with none of the cranial vault suture closed have a foramen magnum height similar to those with cranial vault suture closed.

O presente estudo teve como objetivo examinar a relação das dimensões do crânio e o grau de fechamento das suturas da abóboda craniana. Foram analisados 50 crânios de Myrmecophaga tridactyla Linnaeus, 1758 e 178 de Tamandua tetradactyla Linnaeus, 1758 em relação a 18 dimensões do crânio. Os crânios foram divididos em três grupos quanto ao grau de fechamento da sutura: nenhuma sutura fechada (grau 0), uma ou todas das seguintes suturas fechadas: interfrontalis, sagitalis e coronalis (grau 1) e todas as suturas fechadas (grau 2). Os resultados indicaram que das 18 dimensões 17 apresentaram diferença significativa (p ≤ 0,01) entre grau 0 e grau 1 de T. tetradactyla; entre grau 0 e grau 1, e grau 0 e grau 2 de M. tridactyla. Indivíduos grau 1 e grau 2 de M. tridactylanão apresentaram diferença significativa em nenhuma das 18 dimensões. A altura do forame magno nas duas espécies não apresentou diferença significativa (p > 0,05) entre nenhuma das categorias de sutura (grau 0, grau 1 e grau 2). Em princípio, o nível de fechamento da sutura e as dimensões cranianas estão relacionados. Os espécimes com dimensões cranianas maiores apresentaram maior número de suturas de abóbada craniana fechadas para ambas as espécies de tamanduás. Os espécimes de T. tetradactyla e M. tridactyla sem sutura da abóbada craniana fechada possuem altura do forame magno semelhante àquelas com sutura da abóbada craniana fechada.

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ABSTRACT This study aimed to examine the relationship between skull size and the level of cranial vault suture closure. A total of 50 Myrmecophaga tridactyla Linnaeus, 1758 and 178 Tamandua tetradactyla Linnaeus, 1758 skulls were analyzed in relation to 18 skull dimensions. The skulls were grouped into three levels of suture closure: no sutures closed (level 0), one or all the fallowing sutures closed: interfrontalis, sagitalis and coronalis (level 1) and all sutures closed (level 2). The results indicated that among the 18 variables measured, 17 showed significant differences (p 0.01) between level 0 and level 1 skulls of T. tetradactyla; as well as between level 0 and level 1, and level 0 and level 2 skulls of M. tridactyla. M. tridactyla level 1 and level 2 had no significant difference among any of the 18 dimensions. The foramen magnum height in both species showed no significant difference (p > 0.05) among any suture categories. In principle, suture closure level and cranial dimensions are related. The specimens with larger cranial dimensions showed greater number of cranial vault sutures closed for both species of anteaters. Tamandua tetradactyla and M. tridactyla specimens with none of the cranial vault suture closed have a foramen magnum height similar to those with cranial vault suture closed.

RESUMO O presente estudo teve como objetivo examinar a relação das dimensões do crânio e o grau de fechamento das suturas da abóboda craniana. Foram analisados 50 crânios de Myrmecophaga tridactyla Linnaeus, 1758 e 178 de Tamandua tetradactyla Linnaeus, 1758 em relação a 18 dimensões do crânio. Os crânios foram divididos em três grupos quanto ao grau de fechamento da sutura: nenhuma sutura fechada (grau 0), uma ou todas das seguintes suturas fechadas: interfrontalis, sagitalis e coronalis (grau 1) e todas as suturas fechadas (grau 2). Os resultados indicaram que das 18 dimensões 17 apresentaram diferença significativa (p 0,01) entre grau 0 e grau 1 de T. tetradactyla; entre grau 0 e grau 1, e grau 0 e grau 2 de M. tridactyla. Indivíduos grau 1 e grau 2 de M. tridactyla não apresentaram diferença significativa em nenhuma das 18 dimensões. A altura do forame magno nas duas espécies não apresentou diferença significativa (p > 0,05) entre nenhuma das categorias de sutura (grau 0, grau 1 e grau 2). Em princípio, o nível de fechamento da sutura e as dimensões cranianas estão relacionados. Os espécimes com dimensões cranianas maiores apresentaram maior número de suturas de abóbada craniana fechadas para ambas as espécies de tamanduás. Os espécimes de T. tetradactyla e M. tridactyla sem sutura da abóbada craniana fechada possuem altura do forame magno semelhante àquelas com sutura da abóbada craniana fechada.

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This study aimed to examine the relationship between skull size and the level of cranial vault suture closure. A total of 50 Myrmecophaga tridactyla Linnaeus, 1758 and 178 Tamandua tetradactyla Linnaeus, 1758 skulls were analyzed in relation to 18 skull dimensions. The skulls were grouped into three levels of suture closure: no sutures closed (level 0), one or all the fallowing sutures closed: interfrontalis, sagitalis and coronalis (level 1) and all sutures closed (level 2). The results indicated that among the 18 variables measured, 17 showed significant differences (p ≤ 0.01) between level 0 and level 1 skulls of T. tetradactyla; as well as between level 0 and level 1, and level 0 and level 2 skulls of M. tridactyla. M. tridactyla level 1 and level 2 had no significant difference among any of the 18 dimensions. The foramen magnum height in both species showed no significant difference (p > 0.05) among any suture categories. In principle, suture closure level and cranial dimensions are related. The specimens with larger cranial dimensions showed greater number of cranial vault sutures closed for both species of anteaters. Tamandua tetradactyla and M. tridactyla specimens with none of the cranial vault suture closed have a foramen magnum height similar to those with cranial vault suture closed.(AU)

O presente estudo teve como objetivo examinar a relação das dimensões do crânio e o grau de fechamento das suturas da abóboda craniana. Foram analisados 50 crânios de Myrmecophaga tridactyla Linnaeus, 1758 e 178 de Tamandua tetradactyla Linnaeus, 1758 em relação a 18 dimensões do crânio. Os crânios foram divididos em três grupos quanto ao grau de fechamento da sutura: nenhuma sutura fechada (grau 0), uma ou todas das seguintes suturas fechadas: interfrontalis, sagitalis e coronalis (grau 1) e todas as suturas fechadas (grau 2). Os resultados indicaram que das 18 dimensões 17 apresentaram diferença significativa (p ≤ 0,01) entre grau 0 e grau 1 de T. tetradactyla; entre grau 0 e grau 1, e grau 0 e grau 2 de M. tridactyla. Indivíduos grau 1 e grau 2 de M. tridactylanão apresentaram diferença significativa em nenhuma das 18 dimensões. A altura do forame magno nas duas espécies não apresentou diferença significativa (p > 0,05) entre nenhuma das categorias de sutura (grau 0, grau 1 e grau 2). Em princípio, o nível de fechamento da sutura e as dimensões cranianas estão relacionados. Os espécimes com dimensões cranianas maiores apresentaram maior número de suturas de abóbada craniana fechadas para ambas as espécies de tamanduás. Os espécimes de T. tetradactyla e M. tridactyla sem sutura da abóbada craniana fechada possuem altura do forame magno semelhante àquelas com sutura da abóbada craniana fechada.(AU)

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The Botocudo Indians were hunter-gatherer groups that occupied the East-Central regions of Brazil decimated during the colonial period in the country. During the 19th century, craniometric studies suggested that the Botocudo resembled more the Paleoamerican population of Lagoa Santa than typical Native Americans groups. These results suggest that the Botocudo Indians might represent a population that retained the biological characteristics of early groups of the continent, remaining largely isolated from groups that gave origin to the modern Native South American variation. Moreover, recently, some of the Botocudo remains have been shown to have mitochondrial and autosomal DNA lineages currently found in Polynesian populations. Here, we explore the morphological affinities of Botocudo skulls within a worldwide context. Distinct multivariate analyses based on 32 craniometric variables show that 1) the two individuals with Polynesian DNA sequences have morphological characteristics that fall within the Polynesian and Botocudo variation, making their assignation as Native American specimens problematic, and 2) there are high morphological affinities between Botocudo, Early Americans, and the Polynesian series of Easter Island, which support the early observations that the Botocudo can be seen as retaining the Paleoamerican morphology, particularly when the neurocranium is considered. Although these results do not elucidate the origin of the Polynesian DNA lineages among the Botocudo, they support the hypothesis that the Botocudo represent a case of late survival of ancient Paleoamerican populations, retaining the morphological characteristics of ancestral Late Pleistocene populations from Asia.

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Taxonomy of short-tailed bats (Phyllostomidae: Carollia) has been unclear due to the extreme morphological similarity among species and the significant morphological variation within species. The identity of the Carollia species in Gorgona National Natural Park (Colombian Pacific) has been controversial due to the high morphological similarity between Carollia perspicillata and C. brevicauda. C. perspicillata is common in lowlands, and more likely to be the Gorgona species than C. brevicauda, while geological evidence suggests that common between 1 500 and 3 000m. We recorded eight measurements from jaws and skulls of confirmed C. perspicillata (24 individuals) and C. brevicauda (23) and 35 individuals captured in Gorgona. Discriminant analyses showed that, contrary to expectations based on current altitudinal distributions, the Gorgona population is morphologically closer to C. brevicauda. Biological evidence suggests that Gorgona was connected in the past to mainland South America. Gorgona may be the highest part of a now submerged mountain range (“Cordillera de la Costa”) that was part of the continent during the Pleistocene glaciations. Consequently, I hypothesize that C. brevicauda colonized Gorgona overland during last Pleistocene glaciations. Rev. Biol. Trop. 62 (Suppl. 1): 435-445. Epub 2014 February 01.

La identidad de la especie de Carollia (Chiroptera: Phyllostomidae) en el Parque Nacional Natural Gorgona ha sido controvertida debido a la alta similitud entre C. perspicillata y C. brevicauda. C. perspicillata es la especie con mayor probabilidad de habitar en la isla debido a que actualmente se distribuye en las tierras bajas de la costa pacífica colombiana, mientras C. brevicauda es una especie predominantemente de tierras altas. Con el objetivo de resolver la controversia acerca de la especie del género Carollia que habita la isla, se realizaron análisis morfométricos con base en característica de cráneos y mandíbulas de especímenes de las dos especies y del PNN Gorgona. Los resultados evidenciaron que, contrario a lo esperado, esta población insular es morfológicamente más similar a C. brevicauda. Evidencia biológica para diferentes grupos de organismos sugiere que Gorgona puede haber estado conectada a los andes y las zonas bajas del pacífico del sur de Colombia-norte de Ecuador en el pasado. Por otra parte, existe evidencia geológica que muestra que Gorgona es la parte más alta de una cordillera (Cordillera de la Costa) que se encuentra sumergida actualmente, pero que probablemente fue parte del continente durante el Pleistoceno. Por lo tanto, con base en esta evidencia biológica y geológica se plantea la hipótesis de una ruta de colonización de C. brevicauda a Gorgona desde los Andes a través de la Cordillera de la Costa. Este proceso pudo facilitarse por el descenso marino durante las glaciaciones del Pleistoceno.

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