Six vertebrae (one cervical, three articulated thoracic, and two lumbar) and an incomplete thoracic neural spine from a new late Pleistocene site at Anolaima, Cundinamarca, Colombia, are attributed to the extinct gomphothere (Elephantoidea, Proboscidea) Notiomastodon platensis. The preserved bones exhibit a range of alterations, including porosities, piercings, hollows, and deep bone lesions on the spinous process and the neural arch; asymmetrical zygapophyseal articulations; and osteoarthritic lesions. Diet, behaviour, ecological aspects, selective pressures, and disease have the potential to affect the bones, so the study of individual variations and palaeopathology provides important information for understanding aspects of the life of extinct organisms. Osteological anomalies in the Anolaima gomphothere are interpreted as the result of nutritional deficiencies in essential minerals caused by environmental stresses, possibly related to the palaeoenvironmental instability that characterized the late Pleistocene and that coincides with the age of the fossils. Excessive biomechanical loading on already weakened bones from locomotion through the uneven, upland terrain of the Anolaima region may have contributed to the pathologies. This palaeopathological analysis is the first for Colombian megafauna, and thereby broadens our knowledge of the health conditions of South American gomphotheres.

Although common in the Mediterranean, the morphological and biological characteristics of the moray eel Muraena helena are largely unknown. This study, based on 310 specimens caught using a longline at a depth of 50–100 m, addresses this knowledge gap for northern Tunisia, which is a stronghold of the species. There were significantly more males than females, with a sex ratio of 1:1.5. The number of vertebrae between individuals were variable, especially abdominal and caudal vertebrae (range 56–72; 70–84, respectively). Overall, the total number of vertebrae was less variable (138–146 ± 3.6 SE) and similar between males and females. The length-length relationship recorded for M. helena is provided for the first time, with the pre-anal length (paL), pre-dorsal length (pdL) and the head length (hL) growing faster than the total length (TL). According to the weight-length relationship (WLR), positive allometric growth was established for males (b = 3.6), females (b = 3.46) and combined sexes (b = 3.54). The relative condition factor (CF) did not show significant differences between seasons. The gonadosomatic index (GSI) indicated a significant difference between the seasons for females, whilst the hepatosomatic index (HSI) highlighted a significant difference between seasons for both males and females.

The presence of Halisaurus (Squamata, Mosasauridae) in the uppermost Cretaceous of the Maastrichtian type area, suggested by Lingham-Soliar (1996) on the strength of two partial vertebrae, is questioned. The anatomy of these elements suggests that they pertain not to Halisaurus, but more probably to Plioplatecarpus marshi Dollo, 1882.

The bigeye thresher, Alopias supercilious,is commonly caught as bycatch in pelagic longline fisheries targetingswordfish. Little information is yet available on the biology ofthis species, however. As part of an ongoing study, observers sentaboard fishing vessels have been collecting set of information thatincludes samples of vertebrae, with the aim of investigating ageand growth of A. supercilious. A total of 117 specimenswere sampled between September 2008 and October 2009 in the tropicalnortheastern Atlantic, with specimens ranging from 101 to 242 cmfork length (FL) (176 to 407 cm total length). The A. supercilious vertebraewere generally difficult to read, mainly because they were poorlycalcified, which is typical of Lamniformes sharks. Preliminary trialswere carried out to determine the most efficient band enhancementtechnique for this species, in which crystal violet section stainingwas found to be the best methodology. Estimated ages in this sampleranged from 2 to 22 years for females and 1 to 17 years for males.A version of the von Bertalanffy growth model (VBGF) re-parameterisedto estimate L0, and a modified VBGF using a fixed L0 were fittedto the data. The Akaike information criterion (AIC) was used tocompare these models. The VBGF produced the best results, with thefollowing parameters: Linf = 293 cm FL, k = 0.06 y–1 and L0 = 111 cmFL for females Linf = 206 cm FL, k = 0.18 y–1 and L0 = 93 cm FLfor males. The estimated growth coefficients confirm that A. supercilious isa slow-growing species, highlighting its vulnerability to fishingpressure. It is therefore urgent to carry out more biological researchto inform fishery managers more adequately and address conservationissues.

The occurrence of lead in various bone tissues of Trematomus bernacchii was investigated in order to identify the optimal target tissue and to examine potential relationships between bone lead concentration and fish size and age. Lead concentration values found in vertebrae and jaws (0.44 ± 0.13 and 0.41 ± 0.09 μg g−1 of dry weight tissue, respectively) were significantly higher than those in the other bones examined (otoliths, branchiostegal rays and pectoral girdles), indicating a preferential accumulation of lead in these tissues. Hence, vertebrae and jaws were selected as suitable target organs. The significance of T. bernacchii as a marker of lead bio-availability for the marine environment was tested by comparing data with the ones obtained for the Scorpaena notata, a benthic fish living in the more polluted coasts of the Mediterranean Sea, and by correlating the lead content found in the fish bones with the concentration of bio-available lead in the marine sediments on which the two fishes live. Bio-availability was evaluated by solid speciation and size fractionation techniques. All data clearly indicated that the difference in bone lead content between S. notata and T. bernacchii (0.83 ± 0.17 μg g−1 and 0.42 ± 0.08 μg g−1, significant at the 99.9% confidence level) can be ascribed to the concentration of bio-available lead in their respective environment. Finally, no correlation between the lead accumulation in bone tissues and fish size and age was found for either fish species.

Patterns of growth of caudal vertebrae in the chameleon Chamaeleo dilepis were determined using principal component analysis, and compared to growth of the entire tail relative to snout–vent length. Despite significant positive allometry of the whole tail, growth rates of vertebrae differed along the length of the tail. Specifically, there was a proximal region that grew positively allometrically, and an extensive distal portion that grew with negative allometry. Intervening, was a short transitional region of approximate isometry. Positive allometry of the entire tail resulted from the extensive proximal region that grew in this manner. Although the region of positive allometry extended further caudad than the m. caudofemoralis longus, m. retractor penis magnus, and m. ischiocaudalis, its extent correlated more closely with the presence of neural spines (which are used as a proxy for the extent of the m. transversospinalis) and with tail coiling in this species. The positively allometric region housed the non-segmental musculature of the tail and did not bend, and the negatively allometric region identified the portion of the tail that was prehensile.

Among mammalian morphological specializations to arboreality, prehensile tails are the least studied. In carnivorans, two phylogenetically and ecologically distant representatives possess truly prehensile tails: the kinkajou Potos flavus, a neotropical procyonid and the binturong Arctictis binturong, a viverrid from south-east Asia. This paper examines osteological characters associated with tail prehensility by comparing carnivorans with and without prehensile tails. The prehensile-tailed taxa are characterized by: (a) a relatively longer proximal caudal region in length and number of vertebrae; (b) more robust distal caudal vertebrae, which possess expanded transverse processes. Comparable features have been also reported for prehensile-tailed primates, indicating evolutionary convergence. These features can be functionally associated with enhanced flexion–extension of the proximal part of the tail and increased strength and flexing capacity at the distal end of the tail. These tail movements are briefly described in free-ranging prehensile-tailed carnivorans.

The nominal species Mosasaurus ivoensis from the latest early Campanian of the Kristianstad Basin in southern Sweden, is redescribed and assigned to the tylosaurine genus Tylosaurus on the basis of its dental and vertebral morphology. A partial skeleton (KUVP 1024) from the late Coniacian to earliest Campanian Smoky Hill Chalk Member of the Niobrara Formation in western Kansas, USA, was previously referred to “M”. ivoensis. Nevertheless, its marginal teeth are markedly different, both in size and morphology, from those of topotypic T. ivoensis.

Examination of type specimens and topotypic material of the nominal tylosaurines Hainosaurus pembinensis from the late early Campanian of Manitoba, Canada, H. gaudryi from the late Santonian or early Campanian of northwestern France, and H. lonzeensis from the Coniacian or Santonian of Belgium, indicates that all three may be Tylosaurus.

The utility of isolated tooth-crowns in mosasaur taxonomy has been hampered by the often poor quality of the published illustrations of these fossils in combination with poor stratigraphic control. All Swedish remains of T. ivoensis, including 172 marginal teeth, 6 pterygoid teeth, several jawbone fragments and 12 vertebrae, were collected from a narrow stratigraphic interval corresponding to the highest biozone in the German eight-fold division of the early Campanian, providing the first good insight into the intraspecific dental variation in a tylosaurine mosasaur.

The backbone or vertebral column is the defining feature of vertebrates and is clearly metameric. Given that vertebrae arise from segmented paraxial mesoderm in the embryo, this metamerism is not surprising. Fate mapping studies in a variety of species have shown that ventromedial sclerotome cells of the differentiated somite contribute to the developing vertebrae and ribs. Nevertheless, extensive studies in amniote embryos have produced conflicting data on exactly how embryonic segments relate to those of the adult. To date, much attention has focused on the derivatives of the somites, while relatively little is known about the contribution of other tissues to the formation of the vertebral column. In particular, while it is clear that signals from the notochord induce and maintain proliferation of the sclerotome, and later promote chondrogenesis, the role of the notochord in vertebral segmentation has been largely overlooked. Here, we review the established role of the notochord in vertebral development, and suggest an additional role for the notochord in the segmental patterning of the vertebral column.

Knowledge of the orientation of facet joints in the cervical and upper thoracic region is important for understanding the biomechanical properties and clinical conditions relevant to the neck. The study was undertaken on dry macerated bones from 30 adult male human vertebral columns. The orientation of the superior articular facets in relation to their inclination with the sagittal and transverse planes was examined between C3 and T3 vertebrae in each column. The linear dimensions of the superior articular facets and the width/height ratio were also calculated. The results show that all vertebrae at C3 level and 73% at C4 level displayed posteromedially facing superior articular facets. Similarly at T1 level (C7/T1 joint) and below, all columns showed posterolaterally facing superior articular facets. The level of change in orientation, from posteromedial to posterolateral facing superior facets, was not constant and occurred anywhere between C4 (C3/C4 joint) and T1 (C7/T1 joint). The change in orientation followed 2 different patterns, i.e. sudden or gradual. The C6 vertebra (C5/C6 joint) was the most frequent site to show the transition. The shape of the superior articular facets was circular to oval at C3, C4 and C5 levels and gradually changed to a transversely elongated surface at C7 and T1. These findings correlate well with various cervical movements and associated clinical conditions.

In this study, the axial skeleton of 14 species of tupaiids (tree shrews) was analysed functionally and compared to that of other archontan mammals. Several differences that relate to differential substrate use were found in the ribs and vertebrae. These differences included cranio-caudal width of the ribs; number of thoracic, lumbar, and caudal vertebrae; cranio-caudal width of the atlas; orientation of the spinous process of the axis; length and cranio-caudal width of the spinous processes of the thoracic vertebrae; length of the spinous processes of the lumbar vertebrae; length and orientation of the transverse processes of the lumbar vertebrae; and the number of sacral vertebrae that articulate with the ilia. The ribs and vertebrae of the arboreal Ptilocercus lowii, the only ptilocercine, exhibit adaptations for a stable thorax that probably facilitate bridging locomotion. The vertebral columns of tupaiines, on the other hand, are more mobile and allow more flexion and extension of the spine; this increased flexion and extension increases stride length, which in turn increases speed in bounding or galloping mammals such as terrestrial tupaiines. It is proposed here that the attributes of the thorax of Ptilocercus are primitive for the Tupaiidae, that the ancestral tupaiid was arboreal, that the tupaiine condition is derived, and that the ancestral tupaiine was terrestrial. It is also proposed that: Ptilocercus may be primitive for the Archonta in its axial skeletal features; a stable thorax was first evolved in an arboreal ancestral archontan; the adaptations for stability of the thorax were retained in the Volitantia (dermopterans and chiropterans) for certain locomotor types, including gliding or flying; a mobile thorax evolved in conjunction with the shift to graspleaping in the ancestral euprimate. These scenarios may be further tested by quantitative analyses of vertebral osteology, as well as myological analyses of the epaxial musculature.

Morphological modification of the cetacean vertebral column for axial locomotion was one of many changes that occurred during and after the invasion of aquatic habitats by the ancestors of living whales. These modifications resulted in a column that can be divided into neck, chest, torso, and fluke structural and functional units. Variations in these units allow subdivision of living whales into three morphological groups that reflect differences in regional flexibility of the column and of locomotor style. Both odontocete and mysticete cetaceans exhibit trends toward reduction of relative centrum length in the neck and torso, restricting the flexibility of the column with increasing adaptation to aquatic lifestyles. Mysticetes and physeterid odontocetes retain the archaeocete pattern of constant vertebral shape along the torso, which acts as an undulatory unit. The location of secondary sites of reduced centrum length in non-physeterid odontocetes subdivides them into subgroups, one with reduced posterior, and the other with reduced anterior, torso flexibility. The relationships between particular osteological patterns and swimming styles in living taxa are used to support predictions of swimming style in fossil species after adoption of a fluke in the late Eocene.

The orientation of the superior articular processes in thoracic and lumbar vertebrae differs. The present study was undertaken to investigate the possible mechanism for the change from a posterolaterally facing superior articular surface in the thoracic region to a posteromedially facing curved articular surface in the lumbar region. The material of the study consisted of dry macerated bones of 44 adult human vertebral columns. The orientation of the superior articular process and its relation to the mamillary tubercle (process) was examined between T9 and L5 vertebrae in each column. An abrupt change from the thoracic to lumbar type of articular process was observed in 3 columns (7%). Forty-one (93%) columns showed a gradual change extending over either 2 or 3 successive vertebrae. The present study suggests that the change in the orientation of the superior articular process, from the coronal to the sagittal plane (sagittalisation), occurs due to the change in the direction of weight transmission through zygapophyseal joints at the thoracolumbar junction. It was observed that the gradual sagittalisation of the superior articular process in the transitional zone brought it close to the mamillary tubercle which eventually fused with it. Thus the study suggests that the characteristic posteromedially facing concave superior articular process of lumbar vertebrae may have formed because of the fusion of the articular process and the mamillary tubercle.