Abstracts

Up to quite recent times there were no determinable ichthyosaurian remains from Russia. All finds from the Volgian stage after Bogolubov (1910) were referred to Ophthalmosaurus. For the first time, systematic composition of ichthyosaurs has been recently studied on the basis of new material. For the Middle Volga region it has been done by V. Efimov and for the Lower Volga - by the author. The most ancient find - Ophthalmosaurus calloviensis (Arkhangelsky, 1999) has been described on the basis of anterior paddle from the Callovian of Saratov. Efimov (1991) described ?Ophthalmosaurus on the basis of a humerus from the Kimmeridgian of Ulyanovsk. Ichthyosaurs of the Volgian stage are described on the basis of nearly complete skeletons and are referred to the family Undorosauridae Efimov (1999). Its characteristics are: longipinnate type of anterior forelimb with five primary digits and the late (Cretaceous - subfam. Platypterygiinae Bardet) representatives, unlike the earlier ones (Volgian - subfam. Undorosaurinae Efimov (1999)), have accessory digits. From the Volgian stage of the Volga river basin are known: Undorosaurus Efimov (1999) Paraophthalmosaurus Arkhangelsky (1997)(=Yasykovia Efimov(1999)), Otschevia Efimov (1998). Genus Platypterygius (=Simbirskiasaurus Otschev et Efimov (1985), Plutoniosaurus Efimov (1997)) that is known in the Volga region from the Hauterivian to Upper Cenomanian is referred by us to Undorosauridae.

This study was supported by the Paleontological Society International Research Program (1999, project RGO-822-1).

In 1878, Owen published a brief report on several small phosphatic objects from the Purbeck Limestone Formation (Lower Cretaceous: Berriasian) of Durlston Bay, Dorset. These objects were dubbed 'granicones' and were interpreted as the dermal armour of the small theropod dinosaur Nuthetes, which Owen originally considered to be a lizard, but later referred to the Crocodilia. Since then the granicones have been referred to the ?heterodontosaurid dinosaur Echinodon and to the Stegosauria. Here, we reassess the systematic affinities of the granicones using data from morphology, histology and taphonomy.

Two distinctive granicone morphotypes are recognised. Most granicones (BMNH 48247, BMNH R.16310-11) are small conical ossicles with either a planar or slightly concave base. The granicone surface is studded with numerous small circular or sub-circular tubercles, producing a pustulate texture. A few granicones (BMNH R.16312) have a different morphology and are flat to mildly convex, plate-like structures with a crenulated, sub-oval outline and planar or slightly concave bases. The upper surface displays a pustulate texture very similar to that described above.

Histological analysis confirms that the granicones represent dermal armour; the granicones shares may histological similarities with ankylosaur, squamate and anuran osteoderms. Taphonomic evidence does not support the referral of the granicones to any particular Purbeck taxon, as Purbeck microvertebrates are often found in accumulations composed of the disarticulated elements of many different individuals. The general absence of osteoderms in theropods and heterodontosaurids argue against the referral of the granicones to either Nuthetes or Echinodon.

The complex sculpturing of the granicones is quite unlike that of the 'waffle-like' sculpture of crocodilians and differs substantially from that on the carapace of the Purbeck turtle "Tretosternon" bakewelli. Although superficially similar to ankylosaur osteoderms in overall morphology, no ankylosaur osteoderm possesses the tubercular sculpture present on the granicones. Moreover, ankylosaur osteoderms are considerably thicker dorsoventrally than are the granicones. The sculpturing of the granicones most closely resembles that present on the cephalic osteoderms of helodermatid lizards, such as Heloderma; the gross morphology of many granicones is also consistent with this interpretation. If correctly identified the granicones would represent the earliest-known helodermatid lizard and the first member of this clade to be identified from England. However, such pronouncements must remain tentative until more complete material is recovered.

Some systematists have been promoting a new system of phylogenetic nomenclature in the past ten years, and they have recently published the PhyloCode on the web. Their proposal is to 'complete the cladistic revolution' and have nomenclature follow cladograms precisely. This cements the exclusion of formally named paraphyletic taxa, and other problems of the older system. More worrying, however, is that the PhyloCode team propose that their system should be legally binding, that diagnoses of taxa should have the same status as Linnean names, and should be registered, and precedent established. We've seen some results of this idea in the recent to-and-fro discussion of terminology of theropod clades. Let's take what's good from the new proposals, and hold back the march of further legislation!

Haramiyids have been known since 1847 from isolated teeth from the Rhaetic and Early Jurassic of Europe. With multiple cusps and divided roots, they have been generally regarded as mammals, but they are quite unlike other early mammals, except multituberculates. They agree with multituberculates in having cusps in longitudinal rows, which function by backward chewing movement of the jaw (palinal), (the opposite of rodents), and they have usually been thought of as related to multituberculates.

In 1997 Jenkins et al. reported the discovery of Haramiyavia, with teeth in place in the jaws. This provides the basis for interpreting the isolated teeth hitherto known. Though the molars of Haramiyavia resemble those of the European haramiyids, Jenkins et al. interpreted the occlusion as orthal, rather than palinal. Also, the jaw shows no resemblance to multituberculates, but is at the level of evolution of Morganucodon and Kuehneotherium, with a groove for ear ossicles on the dentary. Consequently Jenkins et al. rejected haramiyid-multituberculate relationship. Haramiyavia has been compared with Theroteinus from the Rhaetic of France. This has blunt cusps on which the wear facets show evidence only of orthal occlusion.

Comparison of Haramiyavia, Thomasia (including Haramiya) and Theroteinus shows that they are sufficiently alike to be classified in the same order, Haramiyida. Could the multituberculates be derived from a member of the Haramiyida? Or were they, as many believe, related to monotremes, triconodonts and therians? The dental evidence bearing on this question will be discussed.

Despite the problems of support when growing to a large body size many extant mammals are capable of rapid locomotion with fully suspended phases in the strides, even at large body sizes. Traditionally a number of anatomical parameters have been identified that allegedly are tightly correlated with running velocity (e.g. Hildebrand, 1974). These are usually identified on a combination of their presence in most animals capable of rapid locomotion and on physical principles, such as velocity and force outputs around the joints. However, their correlation with actual running velocity is often undocumented, and this has implications for palaeontological reconstructions, as running speed in extinct animals is frequently assessed using such anatomical parameters. Garland and Janis (1993) found a significant relationship between the metatarsus/femur ratio, a ratio often termed the "index of cursoriality", and running speed in 48 species of running mammals (r=0.339) and slightly higher correlations within the subgroups Carnivora (r=0.409) and ungulates (r=0.367). However, the few studies made have only employed bivariate analyses, which, from a theoretical point of view, must be too simplified.

The present study used a database of 76 parasagittal, running mammals (no graviportal or saltatorial species were used), and includes peak running speed, body mass and 14 measurement and ratio variables. In contrast to Garland (1983) no significant relationship between body mass and speed was found (p>0.05). In the bivariate analyses forelimb length showed a slight but significant relationship with running speed (DF=74; r=0.283; F=6.458**), but hindlimb length did not, unless normalized for body mass (hindlimb/3?bm: DF=74; r=0.539; F=30.324***). When normalized for body mass (forelimb/3?bm) forelimb length displayed a substantially greater correlation with speed (DF=74; r=0.550; F=32.108***). The limb ratios correlated rather well with speed, e.g. radius/humerus ratio (DF=74; r=0.567; F=34.082***), metacarpus/humerus ratio (DF=74; r=0.553; F=32.615***), metatarsus/femur ratio (DF=74; r=0.558; F=33.421***) or calcaneal tuber/3?body mass (DF=74; r=0.593; F=40.081***). Residual plots revealed no significant departures from linearity or consistency in decreasing variances, so residual variation was considered random. Departure from linearity was also evaluated by polynimal regression, but these models resulted in correlation coefficient highly similar to the ones obtained with linear models. As predicted multiple regression analyses were able to explain more of the residual variation, but also introduces intercorrelation of the "independent" variables. The significance of this was evaluated by computing the eigen values and consistency indices of each regression. Low eigen values (lim 0) and correspondingly high consistency indices (>25-30) are traditionally considered a "warning signal" of possible redundancy of the predictor variables and a problem of fit. However, in a biological sample where multiple anatomical and ratio variables from every species in the database are used in regression analyses intercorrelation of the "independent" variables is probably unavoidable. Significantly (P<0.05) higher correlation coefficients were obtained from multiple regressions (r's up to 0.663 and 0.693 for forelimb and hindlimb parameters, respectively), but the combination of parameters from fore and hindlimbs resulted in the highest correlation coefficients (r's up to 0.768), but the eigen values were usually very low, and the consistency indices high.

References: Garland, T. Jr. (1983): The relationship between running speed and body mass in terrestrial mammals. J. Zool. Lond. 199: 157-170.
Garland, T. Jr. & Janis, C.M. (1993): Does metatarsal/femur ratio predict maximal running speed in cursorial mammals? J. Zool. Lond. 229: 133-151.
Hildebrand, M. (1974): Analysis of Vertebrate Structure. John Wiley & Sons, New York, 710 pp.

Laser cleaning in conservation is a recent science. It has several advantages over other conventional cleaning methods in that it offers the potential for selective and highly controlled removal of surface contaminants. The Natural History Museum in London has acquired a share in a Q-switched Nd:YAG laser and is currently evaluating its use on fossil material. A number of specimens were chosen for cleaning and this poster will show some of the initial results highlighting the advantages and disadvantages of laser cleaning over other conventional techniques such as airbrasive and solvent cleaning.

An imprint of an almost complete skeleton of an hybodont shark has been found in the Wordie Creek formation of East Greenland (basal conodont zone of the Lower Triassic: Hindeodus parvus zone) by one of us (RJT). The specimen measures only 16 cm in length and displays its head, the two dorsal fins, the pectoral fins and much of the vertebral column. Only part of the pelvic girdle is preserved and the pelvic, anal and caudal fins are missing.

The general outline of the animal is very similar to that of Lissodus africanus from the Lower Triassic of South Africa. Unfortunately, secondary recrystallization has obscured most of the neurocranium. The jaws are hardly preserved, but several teeth have been observed, both in an anterior and posterior position. The anterior teeth show a moderately developed main cusp flanked with one pair of lateral cusplets. The main cusp is pyramidal and appears to lack a well-defined labial peg at its base. This is very reminiscent of the genus Polyacrodus and together with the general outline of the animal confirms its attribution to the family Polyacrodontidae. The posterior teeth are more elongated, with a reduced main cusp and up to three pairs of very low lateral cusplets. No cephalic spines have been observed, but as the pelvic fins are missing we cannot certify that this specimen is a female. The dorsal fin spines show a ribbed surface, as typical in many hybodont sharks, but no posterior hooks have been preserved. The posterior fin spine is in a more upright position than the anterior one. The pectoral fins and girdle are quite unusual when compared with other hybodont sharks. The scapulocoracoid is very thin and is more reminiscent of the Carboniferous Hamiltonichthys than that of Hybodus. The propterygium bears one radial while the meso and metapterygium may be partially fused and bear at least 9 radials. The mesopterygium appears to be the largest of the three elements, which is unusual in hybodont sharks. All three participate in the articulation with the scapulocoracoid, which suggests a low degree of rotational mobility for the pectoral fin.

The morphology of the teeth strongly suggests that this fossil belongs to the genus Polyacrodus. It would then be the first complete specimen to be referred to that genus. Polyacrodus may then be characterised by a thin and elongated scapulocoracoid and a well developed mesopterygium partially fused with the metapterygium.

Contrary to popular belief, fossil feathers are not uncommon. Within the Mesozoic there are a significant number of localities that have, and still are, producing fossil feather specimens. Four of these localities are amber producing sites. The feathers that are preserved in amber allow us to gather far more palaeobiological information than the 'normal' preservation seen at other Mesozoic sites. This talk will discuss feathers from the Mesozoic but will mainly concentrate on the new palaeobiological data from the feathers that have been discovered in amber. This new data will aim to show how and when the different types of feathers originated. This information has direct consequences for the theories of feather evolution, the origins of flight and also how 'birds' survived the KT extinction.

Significant numbers of specimens in the palaeontology collections of the Natural History Museum are sensitive to humidity, particularly those from the British Lower Carboniferous and the London Clay horizons. These specimens contain iron pyrite and since current storage conditions within the Palaeontology Building are inadequate to prevent their deterioration, polypropylene and polyethylene food storage containers, 'Stewarts' boxes, as well as individual barrier film enclosures, are used to provide microclimates for individual specimens. However, the large numbers of specimens present practical storage and organisational problems.

An existing collections cabinet - standard in the Palaeontological collections - has been converted to provide environmentally suitable conditions for 300 specimens at particular risk. This in-house, experimental solution has been adopted as an alternative to expensive, purpose built cabinets.

Three stages in this work are detailed: 1. Improved construction of the cabinet with closer fitting doors and seals.
2. Tests to establish the suitability of telemetric environmental data loggers.
3. Enclosure of the cabinet with moisture resistant barrier film 'Marvelseal 470' (Trade Mark).
Desiccant 'Art Sorb' (Trade Mark) cssettes were placed on a shelf in the cabinet to provide the desired humidity. After the intallation of the humidity control agent, continual monitoring of the cabinet as part of the Conservation Unit's environmental monitoring programme shows an acceptable degree of humidity control allowing us to proceed with the installation of the 300 selected specimens.

The phylogenetic relationship of Protornis glarniensis von Meyer, a fossil bird from the Oligocene of Switzerland, is reviewed in light of the proposal that this taxon may be referable to the Recent "coraciiform" family Momotidae (motmots). Since today this group of birds is restricted to the Southern Hemisphere, referral of this Tertiary fossil to the motmots has important paleobiogeographic implications. However, the results of a cladistic analysis including the Recent families of "coraciiforms" leads to the hypothesis that Protornis is the sister-taxon of a clade comprising both the Recent bee-eaters (Meropidae) and motmots (Momotidae). In addition, the majority of the characters used in the referral of this specimen to the Momotidae are primitive at a more general level within "coraciiform" birds.

On the basis of overall similarity with Recent taxa, the presence of a number of groups of fossil birds in the Northern Hemisphere Tertiary has been inferred. The use of cladistic methods of character analysis renders such proposals unlikely.

Hyaenodontidae (Creodonta) was a group of archaic mammalian predators known from Eocene to Miocene. Despite that it was a highly diverse taxon, it has been rather neglected, and reliable locomotor behaviour reconstructions have been rare for most of the hyaenodontid creodonts. In this study, locomotor behaviour estimations were attempted using bivariate regression analyses of limb long bone dimensions (i.e., long bone length, shaft diaphyseal cross-sectional geometries, and articular size of humerus, femur, and tibia). These limb bone dimensions relate to mechanical requirements, such as rigidity against loadings and joint mobilities, during animals' movement. Correlations between locomotory behaviours and the limb bone morphologies are examined using a Recent carnivore sample that includes 47 placental and marsupial species. The species were categorised into the locomotor groups; arboreal, scansorial, terrestrial with generalised, semi-fossorial, and semi-aquatic subgroups, and cursorial. Cursorial and arboreal groups were the easiest to characterise by the limb bone morphologies among the locomotor groups. A few characters differed between taxonomic groups, and these were considered as unuseful for reconstruction of locomotor behaviours.

The fossil sample consisted of 10 North American hyaenodontid genera from Early to Middle Eocene (Wasatchian, Bridgerian, and Uintan) and Early Oligocene (Orellan). Hyaenodontids showed more similarity to marsupials than to carnivorans in some characters (e.g., distal humeral shape, and greater shaft rigidities relative to articular dimensions), presumably suggesting retention of primitive traits. Relatively stronger femora and anteroposteriorly elongated tibial shaft were unique in hyaenodontids compared with Recent carnivores.

The results indicate that hyaenodontids were non-cursorial terrestrial animals in general, but there were some variations. Wasatchian genera, such as Prototomus, had less clear locomotor specialisations. Incipient running adaptations (e.g., the relative humeral dimensions) existed in Arfia and in Pyrocyon. For Prolimnocyon, two different locomotory behaviours, arboreal and semi-fossorial, were suggested based on humeri and distal femora, respectively. Among the Bridgerian taxa, Sinopa probably had both scansorial and amburatory terrestrial locomotions. Tritemnodon seemed to have been more scansorial than Sinopa. Thinocyon compares well to modern small terrestrial carnivores like Mustela. Machaeroides (Bridgerian), and Limnocyon (Bridgerian and Uintan) had the strong humeral shaft relative to bone length, suggesting digging specialisations. Hyaenodon from the Orellan indicates more cursorial adaptations in distal humeral dimensions than any other hyaenodontids, but they were less cursorial than modern canids based on robust and short limbs.

This study was financially supported by Fujiwara Natural History Foundation, Johns Hopkins University Fellowship (to N. Egi), and National Science Foundation (to Dr. K. D. Rose).

It was the beginning of the 20th century when an assemblage of fossil mammals from Pondaung area of central Myanmar was described for the first time. The fauna, except primate species from there, had been neglected for a long time, until several palaeontological expeditions were carried out in late 1990's. Many new fossil specimens have been collected, and a total of 19 genera in five orders are presently known from the Pondaung mammalian fauna. Mammalian genera which have been discovered from the Pondaung Formation are listed in the table below.

The age of the Pondaung Formation has been estimated as upper Middle Eocene. At that time, the Asian continent was separated from either of the Indian, African, or European continents by the Tethys Sea and Turgai Strait. Among the genera known from the Pondaung mammalian fauna, half of them are endemic to the fauna. The fauna also contains some taxa (e.g., Anthracotheriidae, Deperetellidae) that are widely known from other Middle to Upper Eocene localities in east Asia, such as China, Mongolia, and Thailand. Taxa which seem to have come from the west are rare, except that the phyomyid rodent and the proviverrine hyaenodontid may be closely related to African and Indo-Pakistan species, respectively. Among the Middle to Late Eocene mammalian fauna in Asia, late Middle to Late Eocene faunas in southern and central China share a greater number of genera with the Pondaung fauna.

Table: Mammalian genera from Pondaung fauna.

Genera with asterisks (*) are endemic to Pondaung fauna:
1      Gelocidae or Leptomerycidae;
2      Isectolophidae or Hyracodontidae
3      Rhinocerotoidea

Acknowledgements:

This project was supported by Ministry of Defence of the Union of Myanmar and Ministry of Education of

In 1982, Carroll described a small skeleton from the Lystrosaurus zone of South Africa under the name Colubrifer campi. He identified it as a lizard and suggested that its relatively elongate body and short limbs might place it on the ancestry of one of the derived limbless lineages - hence the name. Reexamination of the skull (Museum of Paleontology, Berkeley) permits a very different interpretation. Colubrifer is not a diapsid, much less a lizard. Although the occurence of Triassic squamates is predicted by existing phylogenies, the Triassic history of the group remains unrecorded.

Recent molecular studies, based on the so-called 'molecular clock', suggest that the modern orders of birds and mammals may have originated early in the Cretaceous period. These results deeply challenge the traditional scenario provided by the fossil record, that is, an early Tertiary radiation for these modern groups. In fact, the results of molecular biologists imply that nearly half the fossil record is missing from the last 130 ma. According to these authors, the Cretaceous fossil record of modern birds and mammals may be affected by the small size of the taxa, by unfavourable depositional environments, or by sampling biases. Such a challenge cannot remain unanswered by the palaeontological community, and the quality of the fossil record in the critical interval must be assessed. A preliminary study has shown that the fossil record of Cretaceous tetrapod families is fairly robust throughout the whole period. However, much more data are required to test further the potential factors of incompleteness proposed by molecular biologists. Consequently, a huge database is currently being compiled at the species level for Cretaceous vertebrates. This relational dataset includes information about taxonomy, phylogeny, ecology, geography and stratigraphy. In addition, new techniques are proposed to better qualify and quantify the heterogeneity of data in palaeontological compilations.

Besides flight apparatus, the diverse skull morphology is one of the main characteristics of pterosaurs. Especially the variation in the dentition and the occurrence of crests are of interest for reconstructing life habits and feeding of pterosaurs: the dentition varies in morphology and number of teeth. In some taxa the teeth are reduced, whereas some are entirely edentulous. In the latter case keratinous edges aligned with a sheath like among the Aves is assumed. So far, only speculations exist about the role of the crests. They might have served as rudders for flight manoeuvres or as hydrodynamic stabilisers for collecting prey from below the water surface. It has also been assumed that these crests might have buttressed the rostrum during occlusion.

Major aims of the project are to work out the biomechanical background of the crests and to reconstruct the evolution of edentulous pterosaurs. The studies are based on the analysis of the constructional morphology of the different types of skulls by using Finite Element Analysis (FEM). Therefore, the following questions have to be settled:

- Do the crests have any hydrodynamic effects?

- What is the mechanical impact of the crests?

- What is the constructional difference between skulls with or without teeth with respect to the force transmission inside the skull? What consequences does this have for the architecture of the skull and the velocity of the occlusion?

- Does the reconstruction of maximum loading cases allow predictions on the arrangement of jaw musculature and the optional spaces for air sacs inside the skull?

- Which biomechanically founded modifications of the morphology of the skulls permits a complete reduction of the dentition?

- What can be said about the mechanical properties of potential prey items with respect to the various skull constructions?

Categories of pterosaur skull Konstruktionen are established based on their morphology. The aim is to reconstruct evolutionary pathways that explains the transformation of the Konstruktion-types by elaborating mechanically based inhibiting retrogression factors.

Tomognathus is one of those palaeontological curiosities. Only known from the English Chalk, it is so unusual that it has puzzled several palaeontologists as to its affinities- A.S. Woodward was the last serious investigator to wrestle with it. He thought it to be a stomiatiod-like fish: that is, an advanced teleost represented today by deep sea snaggle-tooths and dragon mouths. The appearance is alluringly but deceptively similar. However, acid preparation of several specimens now shows this fish to be related to Amia, Caturus and other halecomorphs and adds another adaptive dimension to these Amia relatives.

If one needs recent bones for comparative research, there are several methods available for cleaning bones. One such method is the use of dermestid beetles. This technique is particularly suitable for smallest bones. I explain how to keep the beetles, how to prepare the bones and how to prevent damage to the collections.

Among pterosaurs there are at least two basically different types of wing attachment: In the ornithocheirid type the fossa glenoidea is situated in level with the corpora vertebrae, whereas it lies almost lateral to the sternum in the azhdarchid type. Besides this the ornithocheirid pterosaur type has long and slender wings combined with short hind legs. In contrast the azhdarchid type is characterised by short deep wings and long hind legs.

In aircraft the type of wing attachment as well as the wing's shape and arrangement effect the flight characteristics. In 'top deckers' the centre of gravity lies below the wings. This results in a stable flight especially when combined with long wings. 'Bottom deckers' with the centre of gravity above the wings are unstable in flight but easy to manoeuvre, especially if the wings are short. Bottom deckers with V-shaped long wings are designed to be more stable.

Applying aircraft engineering to pterosaur Konstruktionen (sensu Herkner 1999, Salisbury in prep.) the ornithocheirid type pterosaurs appear to have been stable gliders with self-adjustment abilities on cost of manoeuvrability. The flexible long wing finger could compensate turbulences. Little muscle effort was required to control the wing during flight due to the restricted mobility of the wing joints (Wilkinson in prep.). The shallow relief on the scapulocoracoid indicates only weak basal adjustment and upstroke muscles. Steering was done with the hind legs mainly while the lift could be controlled with the wings by adduction movements or alterations of the wing cambering by movements of the propatagium. A minimum gliding speed has to be postulated for the ornithocheirid Konstruktion in order to guarantee steering efficiency.

The azhdarchid Konstruktion performed an increased manoeuvrability compared with the ornithocheirid one, if the ventrally attached wings were held straight laterally. The flight could be stabilised by lifting the wings into a V-position. The pronounced relief of the scapulocoracoid indicates powerful adjustment and upstroke muscles. The short wing finger relative to the arm results in a mass reduction in the periphery of the wing. The strong pectoral and shoulder musculature as indicated by the cristae on the humerus and the scapulocoracoid as well as a considerable mobility of all arm joints indicate an option for active flight and, in consequence, low flight speeds. At low flight speeds, rudder movements are of little efficiency in aircraft. Pterosauria of the azhdarchid Konstruktion, however, could have manoeuvred by altering the wing beat frequency or amplitude as well as the aspect ratio by adduction movements or changing the wing cambering asymmetrically. The long hind legs could have assisted flight manoeuvres, because the wing membrane was attached to the ankle region. The option for flying at low speed is a precondition for the evolution of excessive crests and extremely long necks as seen in some azhdarchid Pterosauria. The azhdarchid bottom decker Konstruktion is unique among flying vertebrates.

References: Herkner, B. (1999): Über die evolutionäre Entstehung des tetrapoden Lokomotionsapparates der Landwirbeltiere. Ein konstruktionsmorphologisches Transformationsmodell auf evolutionstheoretischer Grundlage. - Carolinea Beiheft 13: 1-353.
Salisbury, S.W. (in prep): A biomechanical transformation model for the evolution of the bracing system of extant crocodilians. PhD thesis.

The "Maidstone" iguanodon, an important assemblage of Iguanodon bones is displayed in the dinosaur gallery of the Natural History Museum, London. A cast was required for Maidstone Museum to exhibit, but a very short timescale was imposed by the need to produce a mould in situ and with little disruption to visiting public, and without creating health hazards. The situation was further complicated by the fact that the slab was mounted vertically.

The solution to this problem was to produce a one piece silicone mould and make the supporting jacket with "Jesmonite" ( an acrylic based resin) and glass fibre. This gave a very strong jacket which could be made very quickly and without the need for any fume extraction or special safety requirements. It was also relatively easy to apply vertically. The cast was also made with the same material for similar reasons and gave a good result which was easy to paint with acrylics. After more than 150 years, Maidstone got its Iguanodon back - or at least the first replica produced.

It is generally accepted that tetrapods evolved from sarcopterygian fishes by acquiring features that are characteristic of terrestrial organisms. This evolutionary transformation seems to be well documented by some key fossils, such as Ichthyostega and Acanthostega. But as complete as these fossils are, they cannot inform us about the structural and functional transformations that must have involved the soft tissues and inner organs during evolution.

For example, it is generally accepted that the 'fin girdle' of fishes was separated from the skull and moved caudally to become the shoulder girdle of a tetrapod. For this reason the fin girdle and the shoulder girdle have been homologised. This transformation is also assumed to be responsible for the formation of the neck in tetrapods. However, evolutionary changes can take place only if the mechanical coherence of the organism as a functional unit (entity) is maintained.

The question what functional and engineering constraints lead to this transformation is still unanswered. Further on, dissections of the shoulder girdles of the spiny dogfish (Squalus acanthias) and the bowfin (Amia calva) brought out that in these fishes the fin girdle belongs to the head, as the muscles necessary for feeding and breathing have their origin on its cranial surface. In these fishes the fin girdle cannot be separated from the head and shifted caudally to become the shoulder girdle of a tetrapod. No-one would assume that sharks went on land, but first analysis of the bauplan of other recent lungfishes (Neoceratodus), and crossopterygian fishes (Latimeria) indicate more or less similar situations: the fin girdle is part of the head and cannot be separated without any functional problems.

According to preliminary investigations on some tetrapods (Necturus, Varanus, Tupaia, Homo) three different kinds of shoulder girdles have been distinguished: (1) the shoulder (fin-) girdle of fishes which is a separator for the vertical movement of the jaws and the lateral undulations of the trunk, (2) the shoulder girdle of tetrapods which carries the body weight in a muscular sling and (3) the shoulder girdle of hominids which provides a high degree of movability to the arms.

The goal of this project that will be outlined here is to analyse how the fin girdles and shoulder girdles are integrated in the bauplan of fishes and tetrapods. On this basis it should be possible (1) to point out the constraints leading the evolutionary transitions from fishes to tetrapods, (2) to reconstruct some anatomical details and their functional connections in fossil fishes which might be candidates for the evolutionary transition to land and (3) to find the constraints leading to the further evolution of tetrapods, with particular consideration of the shoulder girdle apparatus.

The Kunkskopf is in Rheinland-Pfalz, and lies 3 km north of the Laacher See in the lower Brohltal south of Burgbrohl, and is a former volcano. Approximately 150.000 yrs ago, this volcano's eruptions of ash and lava covered a vast area. Below this ash and lava were older clays and laminated oilshales; these deposits are approximately 25 Million years old (Upper Oligocene). In the 1890's during looking for ground water on the Kunkskopf, fossil bearing brown coal was found. With this evidence, the Preussische Geologische Landesanstalt dug a test pit in 1926, fossils found included fish remains, insects, leaves, seeds, and fruit. In addition to these, 29 fossil frogs were discovered. This is the greatest occurrence of fossil frogs found in Germany to date and these finds came from a depth of 12 mtrs. In the 1990's, a special feature of a museum on this site as part of a geological trail was thought of (planning in progress). In 1998 a project devised by The Landesamt für Denkmalpflege was agreed for the excavation of this site again, so comprehensive explorations were done (e.g. Geophysical measurement and borings.). But because of climatic and technical difficulties, this excavation had to be abandoned. So at the end of 1999 a very experienced team of field leaders and field preparators were brought together to make a second attempt on this difficult project. This was started on the 18.10 1999. To make this excavation possible an area of ground 20mtrs x 20mtrs was cleared and then a hole 7 mtrs deep was dug with slopping sides of 45 degrees to prevent slumping. Then a Dielen-Press-Verbau Machine with a weight of approximately 17 tons was brought in. This is the first recorded use of this machine for the excavation of fossils, and with the depth to be worked at and the conditions than were expected at this time of the year it was the best chance to be able to complete the digging safely and on time. At first, the weather was good for this time of the year but after a week the temperature dropped to -9 below and then came the ice and snow. The digging area which by now was 10 mtrs deep was getting very difficult. But still out of all this the team found all that was expected and more. The fossils are now being prepared in the laboratory of The Erdgeschichtliche Denkmalpfege and the fossils include numerous plant remains, fish, tadpoles, frogs of three different families, and also remains of turtle, salamander and crocodile.

Being a large biped severely constrains what sorts of body shapes and sizes can be achieved, however, analysis of the two main groups of bipedal dinosaurs - theropods and ornithopods - reveals two different strategies for supporting the body when the body mass is more than 100kg. Twenty five dinosaurs were examined: Theropoda was represented by Herrerasaurus, four ceratosaurians, and eight tetanurans; Ornithopoda was represented by 6 'stem' ornithopods (non-iguanodontians), and 6 iguanodontians. The theropodan masses ranged from less than 100gm (Compsognathus) to over 5,000kg (Tyrannosaurus), while ornithopod masses ranged from 1.75kg (Lesothosaurus) to over 20,000kg (Shantungosaurus).

Analysis of body mass was done by computing the rotational inertias of the axial body about its center of mass. For all dinosaurs examined the rotational inertias about both vertical and transverse axes are much less than that of a cylinder of equal length and mass, especially at large body size. At small body size RIs are similar for all dinosaurs, and this is interpreted to represent the primitive condition. Both theropod clades retain this primitive RI over all body sizes. An abrupt decrease in transverse RI is seen in the clade Iguanodontia, and is interpreted as signaling a major change in the mechanics of body support for these much heavier animals. The vertical RI is lower still in Iguanodontia and is interpreted as an indicator of a radically different style of walking by this group when compared to theropods of equal mass.

The structure of the vertebrae in theropods and ornithopods reflect two different strategies for dealing with support of the axial body. Both groups show increasing height of the neural relative to the length of the body with increasing length. This is interpreted as reflecting the requirement for increased resistance to bending caused by the non-linear increase in body mass with increasing length. Increasing neural spine height will also provide a larger intra-spinous area to distribute stress more evenly. However, ornithopods opted for increasingly taller neural spines with constant transverse width, while theropods increased both the width and height of the neural spines. The development of ossified tendons in large ornithopods is interpreted to be related to the much higher bending moments that need to be resisted and the constraint of increasing intraspinous ligamentous support via increasing neural spine height only.

Since 1992 Prof. Theodorou from the University of Athens has conducted systematic excavations of the Kerasia locality (Greece), which has revealed a rich Upper Miocene fauna. The fauna mainly consists of Perissodactyla (Equidae, Rhinocerotidae) and Artiodactyla (Bovidae, Giraffidae). My PhD research project involves studying the taxonomy of the ruminants (Bovidae and Giraffidae), and the taphonomy and the stratigraphy of the Kerasia locality. Taxonomically undetermined taxa include two species of giraffes, one species of Gazelle, and 5 or 6 different additional species of Bovidae. The fossil material was deposited as bonebeds within fluvial channels. Physical and biogeochemical data collected should provide a better understanding of the pre-burial and post-burial processes. The excavated material comes from six different sites where separate lenses of bonebeds are found. The relations of the different bonebeds in time and space and Kerasia's palaeofluvial system are further research objectives. These fossils will be used to establish correlations with Upper Miocene localities in Greece, Europe and Asia.

Extant camelids (llamas and camels) are virtually unique among mammals in their regular employment of a pacing gait (i.e., a lateral trot gait, rather than a diagonal one - some domestic horses and dogs may also pace). Along with this gait they have a unique form of foot morphology. Their feet are digitigrade, secondarily modified from an unguligrade stance, with the loss of hooves and the addition of a broad foot pad. It is generally assumed that this foot morphology represents an adaptation for pacing, as the foot pad should bestow greater lateral stability during the rolling of the body encountered during pacing.

Several osteological variables correlate with this foot morphology: splaying of the distal ends of the metapodials, a change in phalangeal proportions from the usual artiodactyl condition (especially an elongated first phalanx and a shortened third phalanx), and increased motility at the metacarpal/phalangeal joint.

We compared 15 osteological measurements of the metapodial and phalangeal bones between extant and extinct camelids and extant ruminants with multivariate analyses (Principal Components Analysis on the full range of variables and ternary plots on the phalangeal lengths). We included 28 species of ruminants, 6 species of extant camelids and 18 genera of extinct camelids (all single individuals from the Tertiary of North America, spanning the camelid phylogeny from the most primitive taxon to extinct members of the extant tribes Llamini and Camelini).

Extant camelids and ruminants were clearly distinguishable with both methodologies, separated by a cluster of osteological features that were indicative of digitigrade or unguiligrade foot posture. Among the extinct camelids, the most primitive taxon (the late Eocene - early Oligocene Poebrotherium) clustered with the more primitive ruminants (tragulids), but all other camelids showed some morphological features more typical of modern forms, and a number clustered with the extant camelids.

Assuming that the foot morphology of extant camelids is tightly correlated with their pacing locomotor mode, pacing can be seen to have evolved twice, once within the extant subfamily Camelinae, and once within the extinct family Protolabinae. Additionally, evolutionary change towards a modern cameline-like condition, but not attaining the fully modern type of morphology, was also seen within the subfamilies Stenomylinae and Miolabinae. The trend towards a more modern type of foot morphology, presumably indicative of a change in locomotor behaviour, occurred convergently in these four separate lineages in the late Oligocene or early Miocene, preceding the formation of open grassland habitats in the late Miocene.

A biomechanical analysis of craniodental anatomy and function in synapsid ('mammal like') reptiles across the Permo-Triassic boundary has elucidated unique feeding mechanisms in these very ancient specialised carnivores. A multidisciplinary approach demonstrates that the trophic ecological niches - based on models of skull function - occupied by the plentiful and highly successful predatory gorgonopsids of the Late Permian, were filled after the end-Permian extinction event by the Moschorhinidae (= Akidnognathidae), members of the therocephalian synapsids. Use of modern anatomical data from various fields allows a rigorous appraisal of functional cranial anatomy in these animals. The hypotheses of function generated by this modern anatomical information is tested, and corroborated by the application of Finite Element Analysis (FEA), a 3-D computer modelling technique used by engineers to solve problems of structural mechanics. Therocephalian predators of the Permian Period such as the Lycosuchidae and Scylacosauridae show subtly different craniodental adaptations to those of the contemporaneous Gorgonopsidae. But the 'gorgonopsid ecomorph' niche that was left vacant by the P-Tr extinction was filled by the moschorhinid therocephalians during the earliest Triassic. Moschorhinids partially re-evolved the gorgonopsid cranial type in a previously unrecognised example of convergent evolution, whilst still retaining elements of the characteristic skull mechanisms of therocephalian carnivores. Moschorhinids also show some craniodental adaptations that are only seen in modern felid carnivorans; details which are closely associated with the characteristic feline behavioural approach to predation. As such, these features represent a unique, and exceptionally early example of the 'aeluromorph' carnivore ecotype, and provide robust indications to the predatory habit of these early Mesozoic carnivores. Alongside these similarities, are some aspects of moschorhinid dental morphology that are entirely unique to these therapsids; these features may be rigorously assessed using the approaches in this study to generate a biomechanical model of craniodental function in moschorhinids, and hence refine our current knowledge of Permo-Triassic carnivore guilds. Biomechanical models such as this are dependant upon a synthesis of engineering principles alongside detailed and rigorous experimental anatomical techniques familiar to veterinary and neontological anatomists.

The phylogenetic relationships of early dinosaurs have been the subject of several recent cladistic studies. The great majority of them agreed on the classic division of the group into monophyletic Saurischia (including theropods and sauropodomorphs) and Ornithischia. The position of certain basal forms, however, are debated. In particular, this is the case of the herrerasaurids Herrerasaurus and Staurikosaurus. These forms were considered either as basal theropods or as the sister group of Saurischia + Ornithischia, thus outside Dinosauria.

A partial cladistic study, including 203 postcranial transformation series, assessed the phylogenetic relationships of the major dinosaur groups and the position of the "early dinosaurs". The resulting hypothesis includes a monophyletic Ornithischia and Saurischia, the first including Pisanosaurus, and the latter all other known Triassic dinosaurs. Saurischia is composed of two monophyletic groups: Herrerasauridae - including Herrerasaurus and Staurikosaurus - and Eusaurischia - including Theropoda and Sauropodomorpha. Saturnalia is accepted as the basal-most sauropodomorph, while Guaibasaurus is possibly the sister taxon to Neotheropoda. The position of Eoraptor is controversial, being placed as the sister taxon of either Herrerasauridae or Eusaurischia.

Based on this phylogenetic arrangement a series of characters can be defined as unambiguously apomorphic for Dinosauria including: epipophyses on cranial postaxial cervical vertebrae; ventral keeling extending caudally to the eighth cervical; rib of the fist primordial sacral anterodorsally expanded; elongated deltopectoral crest; partially opened acetabulum; reduced ventral keeling on ischium; femoral head inturned to approximately 45 degrees; presence of a marked lesser trochanter on femur; tibia fitting posteriorly to the ascending process of astragalus; astragalus concave posteriorly and with reduced articular facet for the fibula; proximal prominence on the posterior part of fourth distal tarsal; more robust metatarsals; with IV clearly shorted than III. This set of morphological characters is believed to be diagnostic of Dinosauria within Dinosauromorpha, and some of them are unique to that group amongst "archosaurs".

The Late Miocene (Tortonian), marine Gram Formation of south-west Jutland, Denmark, is a silty, dark micaceous clay, which was deposited in the then eastern North Sea basin. The Formation has yielded abundant invertebrate and vertebrate fossils (Rasmussen, 1966; 1968). Vertebrate remains discovered include sharks, teleostean fish, chelonians and pinnipeds, but whales (order Cetacea) constitute a remarkably abundant element. Until this date some 18 specimens of whales have been discovered in different states of articulation in the former clay pit at Gram in south west Jutland, Denmark. The whale fauna is dominated by baleen whales (suborder Mysticeti), with only one or two genera of toothed whales (suborder Odontoceti) present. However, so far only two species of whale from the Gram Formation have been identified or described; the cetothere-grade baleen whales Amphicetus rotundus Van Beneden 1880 (unpubl.) and Mesocetus argillarius (Roth, 1978).

This poster presents a preliminary report on another species of cetothere-grade baleen whale from the Gram Formation. The studied specimen consists of a well-preserved braincase with associated rostral bones, along with a few elements of the appendicular skeleton. The braincase shows a mix of phylogenetically primitive and advanced features. Among these features are: supraoccipital process gradually sloping outwards from interorbital region (primitive feature), apex of supraoccipital shield situated anterior to level of extremities of zygomatic processes (advanced feature), parietal wall of temporal fossa almost vertical (advanced feature), and a marked anteroposterior constriction of squamosal-basioccipital complex (advanced feature). The specimen appears very similar to Plesiocetus dyticus Cabrera 1926 from the Miocene of Patagonia, Argentina, possibly representing a new species of the genus. The specimen (numbered MSM/P820) is housed at Midtsønderjyllands Museum in Gram, Denmark.

The study of the evolution of the baleen whales suffers from the fact that many genera and species, which seem intermediate between early, toothed baleen whales, and modern grey whales (family Eschrichtiidae) and rorquals (family Balaenopteridae), have been assigned to the paraphyletic family Cetotheriidae. This family has become an unfortunate assemblage that includes dubious genera and species. To this date, no phylogenetic analysis that includes extinct baleen whale genera has been made. Further studies are needed to determine the exact relationships between cetothere-grade baleen whales, and extant and extinct balaenopterids and eschrichtids.

Alfred Nicholson Leeds (1847-1917), was a gentleman farmer and amateur fossil hunter who, together with his brother Charles Edward Leeds (1845-1912), amassed a prodigious quantity of fossil vertebrates. The fossils, derived from the Oxford Clay,

were found in the Peterborough brick pits near his home at Eyebury (Leeds, 1956). Material collected up until 1889 (the 'first Leeds Collection', already including a large number of type and figured specimens), was sold to the British Museum (Natural History) [now the Natural History Museum, London] in 1889, two years after Charles Leeds emigrated to New Zealand. In the ensuing years, and up to his death in 1917, Alfred Leeds built up a 'second collection', and specimens were sold to the BM(NH), institutions throughout mainland Europe (largely through the auspices of Herr B. Stürtz in Bonn, Germany), and the United States of America. Upon the death of Alfred Leeds, the remainder of the collection, excluding a small amount of material retained by Mrs Leeds (later passing to the BM (NH)), was sold, most going to the Hunterian Museum (Glasgow University). Today, the Leeds collections form an invaluable core for research work into a wide range of Callovian marine vertebrates, including pliosaurs, plesiosaurs, ichthyosaurs, crocodiles and fish.

Alfred Leeds was extremely rigorous in recording details of his fossil finds. The brick pit, depth, year and month of collection were all recorded. Unfortunately, correlating outdated brick pit numbers and details, with map locations and existing working or disused pits is proving problematic. In-depth socio-historical and archival research is beginning to reveal a broad retrospective stratigraphic correlation that can be applied to the Leeds collections. Continuing work on the archival records is allowing the unity of museum material to be checked, and in some cases positively reuniting previously disparate material. This study indicates the value of using all possible sources of data when studying historical fossil material. The fossils alone contain much information, but in association with archive material, and considerable lateral thinking, an even fuller picture of the Callovian seas is emerging. There is still much to come out of the Leeds Collections.

Since it was first described in 1889 (Woodward, 1889), the fish Leedsichthys problematicus has shed little light on its anatomy or taxonomic affinities. Rarely have more than a handful of its bones been found at any one time, an indicator that an animal as large as this one was (estimates have ranged from an original of 30 feet to a more contemporary one of 27 metres (Martill, 1985)), was both unlikely to have a fully ossified and easily preservable skeleton, and equally unlikely to be allowed by marine scavengers to lie still as a protein source when it died.

In June of 1915, a specimen of this animal (V3363) was acquired from Alfred Leeds, the gentleman farmer/amateur fossil hunter and original discoverer of the type material (Leeds, 1956), by Glasgow University's Hunterian Museum (Liston, 1999). The member of staff in post at the time took receipt of the material, but was already working on a reconstruction of an Ophthalmosaurus (bought from the same collector earlier in the year), and did not start work on the specimen before he left unexpectedly a couple of years later. Subsequent staff members did not work on the material, and it languished for over 80 years in store.

A recent survey of other museum collections with similar holdings has indicated that the twenty drawers of material associated with this animal make it probably the most complete individual specimen attributed to Leedsichthys, and the possibility that it might serve as a form of 'Rosetta Stone' with which to understand the anatomy of this animal, and from this, its likely taxonomic relationships with other fossil fishes.

An articulated skeleton of a large ichthyosaur has been excavated over the period of three summers since 1998 from the Norian (Upper Triassic) Pardonet Formation, near Shikanni Chief, British Columbia, Canada. We have collected the skull, cervical, dorsal, and caudal vertebrae, forelimb elements, and a possible tibia. The skull is estimated to be 5.8 m in length, and the total body length 23 m. It is the largest marine reptile known to date. It is 20% shorter than blue whales and about the same size as sperm whales. It is 30% longer than the previously known largest marine reptile, Shonisaurus of the Carnian (Upper Triassic) Luning Formation of Nevada. Only the dorsal side of the postorbital skull has been prepared as of the summer of 2000. There are small upper temporal fenestrae with huge anterior terraces. The parietal foramen is raised on the sagittal crest dividing the large anterior terraces. We cannot make a comparison with Shonisaurus, the roughly contemporaneous large ichthyosaur, because this area of Shonisaurus is not well known. The tail does not seem to have a distinctive tail bend. It however has a significant reduction in the diameter of caudal centrum from 20 cm to 5 cm in height at the posterior caudals. It is quite different from Shonisaurus in the morphology of the humerus, for example. In order to draw even tentative systematic conclusions, we have to await for further preparation, especially of the ventral side of the postorbital skull.

Ichthyosaurs exhibit their adaptive radiation in the Middle Triassic, and the early Late Triassic saw the first examples of gigantic ichthyosaurs like ours, Shonisaurus, and Himalayasaurus of China. This may suggest that the ecosystem was equipped with an ecological and environmental background that enabled ichthyosaurs to achieve such gigantic size by the early Late Triassic.

Fossil vertebrates have been collected from many sites along the Yorkshire coast for over 230 years. In the past ten years, several finds from the Upper Lias (Lower Toarcian) and Middle Jurassic (Aalenian) have been made by local collectors and staff at the Yorkshire Museum, York. Earlier finds from the Yorkshire coast have often proved difficult to establish their provenance; given specimens were poorly recorded or their geographical locality withheld. The recent finds have been mapped and recorded, providing a useful group of specimens for comparison with earlier material with alleged accounts of their provenance. An articulated, near complete ichthyosaur from the Alum Shale Formation (Toarcian; Hildoceras bifrons zone; Dactylioceras commune subzone) was excavated during August 2000 in a quarry north of Whitby. This specimen has provided hitherto unrecorded skeletal elements from Yorkshire coast ichthyosaurs allowing the taxonomic position of one group to be clarified. The preparation and future study of this particular specimen may yield additional information.

Other recent finds from the Yorkshire coast include:

Hybodont shark Hybodus(?)
YORM: 1996.384
Upper Lias, (Hildoceras bifrons zone).
Port Mulgrave, North Yorkshire.
Description: Complete skull (3-dimensional) with teeth in jaws. Crocodile Stenosaurus g racilirostris
YORM: 1994.3163
Upper Lias, (Hildoceras bifrons zone).
Whitby, North Yorkshire.
Description: Complete skull (3-dimensional) and partial skeleton. Skull shows evidence of soft tissue preservation on snout. Dinosaur Tracks Middle Jurrasic (Aalenian-Bathonian).
Scarborough to north of Port Mulgrave, North Yorkshire.
Description: Huge variety of ichnospecies from small gracile theropod (Grallalor sp.) to large sauropod (Brontopodus sp.) tracks.

Isolated dinosaur bones from the south west foreshore of the Isle of Wight have been found with adherent spherical bodies resembling small eggs. The bones are derived from plant debris beds within the Wessex Formation (Early Cretaceous, Barremian) and are preserved in three dimensions and have adherent sideritic mudstone with entrained fragmental plant material. The egg-like bodies are of even size and arranged in clusters of crudely aligned rows. Such clusters have been found on indeterminate limb bones, a sauropod cervical vertebra and the internal mould of the large unionid Margaratifera valdensis. Cluster size varies with large clusters covering several square centimetres and containing hundreds of egg-like bodies. Thin section and scanning electron microscope analysis revealed the presence of embryonic gastropods within the egg-like bodies confirming their true nature and molluscan origin.

Individual eggs are conjoined to adjacent eggs by a thin, hollow neck of mineralised capsule in the manner of a string of beads. The capsule is mineralised in a radial calcite, but this may not be primary. Identification of the gastropod from the embryonic conch is not possible, Two gastropod genera occur in the largely freshwater Wessex Formation. A globose gastropod attributed to the Recent Viviparus and a smaller conch with a inflated body whorl is attributed to the Recent Physa. Physa would appear too small to have produced the eggs found on the bones. The so-called Viviparus could have been the source of the eggs, but Recent Viviparus produce live young. Two other possible candidates on morphological grounds are Bithynia and a freshwater neritid.

Gastropods are rarely encountered in the plant debris beds of the Wessex Formation (the source of most of the dinosaur bones found on the foreshore), Their rarity at these levels being attributed, in part, to diagenetic removal rather than their absence. The presence of gastropods eggs attests to their presence at these levels. The preservation of the eggs may be attributed in part to the microenvironment established in the immediate vicinity of the dinosaur bone. The mineral component of the bone acting as a buffer to the mildly acidic porewaters of the plant debris beds.

There has been a 'problem', since the very start of vertebrate palaeontology, with trade in fossils, and with the relationship between academics and traders. Although curators and palaeontologists have always relied on this trade (since few of us can really collect world-class specimens from the field) there remains a reluctance to legitimise it, exacerbated in the past 25 years by a spate of internationally important fossils 'for sale' coincident with internationally-effective legislation prohibiting it. The laws, based anyway on protection of trade in 'culture', serve mainly to create corrupt systems that benefit nobody except a few 'bent' dealers. We need a new approach.

A model of the jaw mechanics of the Cretaceous carnivorous dinosaur Carnotaurus sastrei BONAPARTE is proposed, including an analysis of cranial kinesis. Jaw muscles were reconstructed by comparison with crocodiles and birds and their corresponding moment arms were estimated. Resistant Fit Theta Rho Analysis (RFTRA), a shape analysis method, was applied to assist in the comparison of the cranial morphology of this species with that of Ceratosaurus nasicornis MARSH. This comparison was used as a basis for analysing cranial differences within the framework of a functional analysis of the feeding mechanisms of Carnotaurus. Study of the jaw mechanics suggests that Carnotaurus had a fast rather than a strong bite. The highly kinetic skull and jaws of this species facilitated an increased oral gape allowing the accommodation of large pieces of meat. Also, the high degree of kinesis might be an adaptation for maintaining the orientation of the eyes with respect to the prey. In Carnotaurus, as in birds, the prokinetic hinge is anterior to the orbits, and consequently the position of the portion of the skull that houses the eyes did not change during the elevation or depression of the upper jaws. Thus, if the eyes of Carnotaurus were fixed on its potential prey, the movements of the jaws would not displace the prey from the line of sight. The results obtained using RFTRA would indicate that the cranium of Carnotaurus shows a much greater degree of dorsoventral vaulting than observed in Ceratosaurus. This also suggests that the cranium of Carnotaurus evolved by vertical expansion rather than by longitudinal shrinking, which is consistent with the rapid bite hypothesis. All of the aforementioned features are consistent with the lifestyle of an active predator that chased and swallow whole fast, small prey.

Theropod dinosaurs are the rarest of all the terrestrial vertebrate groups reported from the Purbeck Limestone Formation. The only taxon from the Isle of Purbeck is Nuthetes destructor, first described by Richard Owen in 1854 as a carnivorous lizard on the basis of the fragment of a small left dentary collected by Charles Wilcox from Austen's (1852) Bed k93. The Nuthetes material was recognised as theropod by Swinton (1934) who identified it as a megalosaur. Most recently, Molnar et al. (1990) listed Nuthetes as a carnosaur nomen dubium. A few compressed and strongly recurved teeth with denticulated mesial and distal carinae are preserved in the jaw fragments; most of the isolated teeth match them closely. Some characters of theropod teeth, particularly the detailed morphology of the denticles on the mesial and distal carinae and the denticle size difference index (DSDI), have taxonomic value at family level. The data obtained for Nuthetes suggests possible dromaeosaurid affinities. The earliest dromaeosaurid occurrences, based on tooth morphotypes, are from the latest Jurassic in both North America and Europe.

A large isolated tooth crown from an unknown Purbeck locality, referred to Megalosaurus dunkeri Dames by Lydekker (1888) shows similar denticle morphology and DSDI values to isolated tooth crowns from the Purbeck of Aylesbury, Buckinghamshire. Although they are not determinate, pending a revision of British 'megalosaurs', they and an isolated metatarsal are representative of a least one large theropod in the British Purbeck.

Messel Pit is located close to the small village of Messel, about 9 km NE of Darmstadt (Hessian State, southern Germany). It is an ancient open-cast mine in which oilshales were quarried until the end of 1971. These oilshales originated from sludge deposits at the bottom of a freshwater lake and were dated as lowermost Middle Eocene, Lower Geiseltalian, Mammal Unit MP 11 (Franzen and Haubold, 1986). The locality was declared a monument on the World Heritage List of the UNESCO in 1995. The mammals are of special importance because they demonstrate the rather rapid radiation of this group since the beginning of the Tertiary. Messel fossils are well-known for their soft tissue preservation: Details of feathers and fur became outlined by petrified bacteria and contents of the digestive tract also were preserved in a similar way.

On the one hand, with reference to the richness and completeness of the fossil record, Messel Pit may be considered as a death trap. However, there are no mass mortality layers, and the fossils accumulated over a long period of time (at least, some hundreds of thousands of years). On the other hand, and with special respect to the ichthyofauna, Messel Pit may be considered as a cradle of species. Seven nominal genera and species have been described so far (Grande and Micklich, 1993; Micklich, 1996). Within most of these species, there are individuals that markedly differ from all other specimens in the development of peculiar skeletal features. Some of them may result from well-known phenomena, e.g., modifications that occur in the course of ontogeny (intraspecific variation). Others are far beyond the range of variability that is reported for any extant species and may be best explained as the result of a diversification process, similar to intralacustrine speciation. The Messel ichthyofauna may be a 'flock' of closely related species. Some may have repeatedly invaded the lake from the drainage system; some permanent stem species or populations may have independently developed within Lake Messel during temporary isolations (e.g., low water periods).

References
Franzen, J.L. & Haubold, H. (1986) < #150; Modern Geology, 10: 159-170.
Grande, L. & Micklich, N. (1993) < #150;- Kaupia,. Darmstädter Beiträge zur Naturgeschichte, 3: 245-255.
Micklich, N. (1996) < #150; Publicaciones Especiales Instituto Espaniol de Oceanografía, 21: 113-127.

A new genus and species of coelurosaurian theropod, discovered in a plant debris bed of the Wessex Formation (Barremian) on the southwest of the Isle of Wight, is represented by a partial skeleton. Material includes a partial cranium, axis and other vertebrae, scapulocoracoid, humerus, partial manus, tibia, fibula, metatarsals and pedal phalanges. These elements show that the taxon was gracile with elongate legs and hands. It appears to have had a deep head with a laterally flat maxilla in which the antorbital fossa seems to have been located relatively caudodorsally. The dentary has nearly parallel dorsal and ventral borders. The most remarkable feature is the nasals, which are totally fused together without any suture line and would have formed a virtually horizontal dorsal border to the snout. The premaxillary teeth are D-shaped in cross section; the maxillary and dentary teeth are laterally compressed and with denticulations that are complete across the tooth tip. The animal would have been 4-5 m long in life: lack of neurocentral, scapulocoracoid and sacral fusion indicates that the individual was not adult. Comparisons with the named Wealden Group theropods show that the new specimen is not synonymous with any of them, nor with any other named theropod taxa, and thus it represents a new genus and species. While some of the named Wealden Group taxa are based on material not represented in the new taxon, they appear to belong to groups from which the new specimen can be excluded (e.g. compsognathids, oviraptorosaurs). The affinities of the new form with other coelurosaurs are problematic, as it lacks characters that allow allocation to a recognised clade. It has superficial similarities with tyrannosaurids but whether these reflect homoplasy or an affinity remains to be determined. There are also superficial similarities between the new taxon and the gracile coelurosaurs Nedcolbertia, Nqwebasaurus and others. Do these indicate phylogenetic affinities or the plesiomorphic coelurosaurian bauplan? The specimen was originally part of a siderite concretion in which elements of a dryosaurid (cf. Valdosaurus) and an isolated ulna from a large theropod were also included. Some of the bones appear to have been subjected to trampling while others were preserved as if still in articulation.

The Callovian marine fauna of the Peterborough Member, Oxford Clay Formation is exceptionally well known, following more than 150 years of intensive collecting. The discovery of a new genus of pliosaur, Pachycostasaurus dawni (Cruickshank, Martill and Noè, 1996), came as something of a surprise - the first new Callovian pliosaur genus described for over 80 years. As a presumably rare member of the Oxford Clay seas fauna, it has been suggested Pachycostasaurus represents an individual from outside the Oxford Clay seas, or possibly the juvenile of an existing species. The remains consist of a substantially complete skeleton with an incomplete skull. The postcranial skeleton exhibits marked pachyostosis in the region of the vertebrae, dorsal ribs and gastralia, only the second pliosaur thus described.

The skull of Pachycostasaurus dawni is considerably crushed and rather incomplete, preserving the pre-orbital region of the snout, the palate anterior of the posterior interpterygoid vacuities and the disarticulated lower jaw anterior of the mandibular condyles. Over 100 teeth and tooth fragments are also preserved, largely scattered over the skull. The cranial material was only briefly considered in the original description, but is important in deducing the taxonomic position of this comparatively new genus. Investigation into the cranial anatomy, and comparison to the better known Callovian pliosaurs Liopleurodon ferox and Simolestes vorax has allowed a preliminary reconstruction of the skull and dentition to be presented. Thus the skull is beginning to answer some of the questions raised by this enigmatic pliosaur.

The ornithopod dinosaur Rhabdodon priscus was first described in 1869 by Matheron on the basis of a few cranial and skeletal fragments collected from the Late Cretaceous of France (Provence). At the turn of the 19th century new ornithopod material was described by F.B. Nopcsa as part of a rich fauna recovered from the Late Cretaceous of Transylvania (Hungary/Romania). Some of this ornithopod material (the fauna also included the distinctive hadrosaurian Telmatosaurus) was attributed firstly to the genus Mochlodon (a name coined from more ornithopod material from the Gosau Formation in Austria), but later to the genus Rhabdodon as two species: R. suessi and R. robustus. This latter genus formed the subject of a series of papers published by Nopcsa during the early decades of the 20th century. Nopcsa assigned the Romanian genus Rhabdodon to a variety of higher categories within the Ornithopoda (to the families Camptosauridae or Iguanodontidae). Latterly it has often been referred to as a member of the 'family' Hypsilophodontidae (sensu Galton) or as a basal iguanodontian. All in all the material attributed to this genus from Romania has had a chequered career.

In recent years the original material, and newly recovered materials collected from additional sites in Romania, has been restudied in the hope of being able to clarify aspects of: i. its anatomy and, ii. its systematic position as an ornithopod dinosaur. It has become clear from this work that the Romanian genus is distinct from the taxon described originally in France, but that it exists (as Nopcsa claimed) as at least two morphs; this ornithopod is also very anatomically unusual when compared with other reasonably well-understood ornithopods.

Incorporating the data derived from the Romanian ornithopod material into a data matrix of information on basal (non-hadrosaurian) ornithopods, creates a number of interesting results in the summary ornithopod cladograms. These results prompt the investigation of assumptions concerning character status and transformational change when mapped on to a cladogram that is being used to interpret the phylogeny of ornithopods more generally.

The Early Triassic was an important period documenting the recovery of faunas and floras after the end-Permian extinction. Much has been written about extinction and survivorship across the Permo-Triassic boundary, and about patterns of dispersal around the Early Triassic world. However, valid comparisons between localities require a precise understanding of how taphonomy, sedimentology and collection methodology have influenced each of the fossil assemblages recovered. This type of detailed information is rarely published, but without it, we are unable to use locality assemblage data to draw meaningful conclusions about the biogeography, ecology, or dispersal patterns of the fauna and flora, or to understand the degree of interchange, if any, between northern and southern regions of Pangea during the Early Triassic. The main aim of the Early Triassic web site is to provide a collection and distribution point for clear, detailed and up-to-date information about Early Triassic deposits and localities. Comparisons between localities should be facilitated by having a standard format for data recording and presentation. Everyone with an interest in the Early Triassic is encouraged to visit the site, make use of the data available, and, if possible, contribute to its content. We recognise that funding constraints in all areas mean that long term, detailed, site-based studies are rarely possible, yet a large body of data may exist in unpublished form in field notebooks or geology students' work books or projects. At the moment a quick perusal of the site will reveal more gaps than data. All contributions are welcome and will be acknowledged.

Analysis of recurrent patterns of wear and surface damage can be a powerful tool in understanding tooth function. In particular, studies of microwear in mammal teeth have revealed that distinctive polished, scratched, or pitted textures are produced in vivo by the action of abrasives in food and by the compressive and shearing forces that act on enamel during feeding (e.g., Teaford, 1988). By comparison with the textures observed in extant taxa, microwear can be used to interpret tooth use, food and feeding in fossils (e.g., Solounias and Hayek, 1993), but almost all analyses of microwear have been restricted to mammals. Recent work on conodonts has demonstrated the potential power of the technique in investigating feeding in other groups of vertebrates (Purnell, 1995; Donoghue and Purnell, 1999), but at present, microwear patterns observed in fossil teeth can be compared only with those documented for mammals.

In order to address this problem the relationship between feeding mechanisms, food type and tooth wear has been studied in several species of African cichlid fish. The results of this analysis strongly support the hypothesis that tooth wear preserves direct evidence of tooth movements during food acquisition, and of the relative abrasiveness of the substrate from which food is obtained. They also support the hypothesis that tooth wear reflects the hardness/abrasiveness of the food.

Wear patterns thus have the potential to reveal hitherto unknown details of feeding in extant and extinct aquatic vertebrates. Direct observation of teeth in use during feeding is obviously impossible for extinct taxa, but patterns of tooth wear resulting from normal use in vivo represent the next best thing. And because the evidence from wear is independent of analyses of tooth function based on morphology, the relationship between tooth form and function can be investigated with much greater rigour. Furthermore, diet is a major factor in determining ecological niches (e.g., Schluter and McPhail, 1992) and tooth wear may prove useful in studying the role of niche differentiation in speciation in both fossil and extant aquatic vertebrates.

References
: Donoghue, P. C. J. & Purnell, M. A. 1999: Mammal-like occlusion in conodonts. Paleobiology 25, 58-74.
Purnell, M. A. 1995: Microwear on conodont elements and macrophagy in the first vertebrates. Nature 374, 798-800.
Schluter, D. & McPhail, J. D. 1992: Ecological character displacement and speciation in sticklebacks. American Naturalist 140, 85-108.
Solounias, N. & Hayek, L.-A. C. 1993: New methods of tooth microwear analysis and application to dietary determination of two extinct antelopes. Journal of Zoology 229, 421-445.
Teaford, M. F. 1988: A review of dental microwear and diet in modern mammals. Scanning Microscopy 2, 1149-1166.

Hybodont sharks were common during the Early Jurassic and shark faunas from this time usually include at least two large hybodonts and occasionally one or two smaller species. The four common genera of hybodonts can be divided ecologically into two groups. Acrodus and Lissodus were equipped with low-crowned teeth, adapted for an invertebrate diet, while Hybodus and Polyacrodus had higher, piercing tooth-crowns, better suited for a diet of fish and cephalopods. Hybodonts were never exclusively marine and their remains can also be found in brackish and fresh-water deposits. Neoselachian sharks had a low diversity in the Early Jurassic and were generally quite small. Palaeospinacid neoselachians are well represented in the Early Jurassic and are known from both isolated teeth and articulated skeletons. The most common non-palaeospinacid neoselachian in the Sinemurian and Pliensbachian of northwest Europe is Agaleus dorsetensis, an enigmatic galeomorph. Few other neoselachians are found in pre-Toarcian sediments but there are scattered records of hexanchids and orthacodontids. Several modern neoselachian groups have their first occurrence in the Toarcian, including the Heterodontidae, the Brachaeluridae and the Rhinobatidae.

So far, three shark faunas have been discovered in the Early Jurassic of southern Scandinavia. Two Pliensbachian tooth assemblages have been extracted, one from the Hasle Formation on Bornholm (Denmark) and another from the Katslösa member south of Helsingborg (Sweden). There is also a fauna of uncertain stratigraphic position within the Early Jurassic from the Helsingborg area.

Shark remains from the Hasle Formation on Bornholm are quite common and the fauna is similar to Sinemurian and Pliensbachian faunas from other parts of Europe. It includes two large hybodonts, Hybodus reticulatus and H. delabechei as well as the smaller, seemingly endemic, species Lissodus hasleensis. As yet, no teeth of Acrodus have been found and this genus appears to have become extinct in the Sinemurian, as it is absent in all the Pliensbachian faunas studied thus far. The neoselachian part of the fauna includes Synechodus occultidens, Paraorthacodus sp., and Agaleus dorsetensis.

A recent excavation at a construction site south of Helsingborg exposed silt and clay of the Katslösa Member. Bulk sampling of these sediments yielded a small, but diverse, shark fauna. Only one hybodont is present, Hybodus reticulatus, but the neoselachian part of the fauna comprises seven taxa, including four palaeospinacids; Synechodus occultidens, S. enniskilleni, "Synechodus" sp. and Paraorthacodus sp. The other three species include the orthacodontid Sphenodus sp., Agaleus dorsetensis and an indeterminate hexanchid. The Katslösa member has yielded the most diverse, pre-Toarcian, neoselachian, fauna ever recorded.

Collections of Jurassic sediments kept at the Department of Geology, Lund University, include a large number of slabs from a bone bed collected in the Helsingborg area. The precise location from where the samples are derived is not known and consequently the precise age is doubtful. Lithologically, the sediments are similar to those of the Döshult member, which is of early Sinemurian age. All teeth extracted thus far belong to the superfamily Hybodontoidea and include Lissodus, Polyacrodus and Hybodus. The composition of the selachian fauna indicates that the sediments were deposited in a non-marine environment.

Amniotes are widely perceived as a paradigm of evolutionary success, as documented by 315 million years of extraordinary taxonomic and ecological diversification. Amniotes include extant reptiles, birds and mammals, but many additional groups of extinct amniotes, including dinosaurs, aquatic reptiles and flying reptiles are also spectacular components of this large clade. In order to gain an understanding of the evolutionary history of this group, it is important to study the patterns of diversification of amniotes, especially the earliest stages of this evolutionary radiation.

Recent advances in our understanding of the origins and early history of amniotes has led to the reconstruction of well supported hypotheses of evolutionary relationships. It has therefore become possible to reconstruct for the first time the general patterns of amniote diversification, especially if we use the comparative method.

Whereas the evolutionary history of many invertebrate and lower vertebrate groups is associated with aquatic environments, the early history of amniotes appears to have been restricted almost entirely to terrestrial habitats. The fossil record of the Palaeozoic provides clear evidence that the synapsid part of the basal amniote dichotomy diversified much more rapidly than the sauropsid branch, and maintained a dominant role on land until the end of that era.

A rich assemblage of lacertilian morphotypes is known from the open-cast coal mining pit Geiseltal near Halle (Saale). Since the 1920's some authors reported many new lacertilian taxa from that fossil locality (Weigelt, 1929; Kuhn, 1940; Kuhn, 1944; Haubold,1977), which were only briefly described and in a few cases revised by later workers (e.g., Estes, 1983; Sullivan et al., 1999). The prepared specimens are mostly very fragile and show all stages of a taphonomic induced embedding: preserved are complete skeletons, slightly disarticulated and wholly scattered remains, respectively. All specimens show traces of a sediment pressure induced crushing, preventing detailed osteological analysis.

This paper was part of a revision (DFG project HA-1872/2-1) of the lacertilian fauna after the final end of the digging campaign within the Geiseltal pit. At the present stage of knowledge, the lacertilian fauna from the Geiseltal comprises the following taxa:

Iguania
Corytophanidae
Geiseltaliellus longicaudus Kuhn, 1944
(= Capitolacerta dubia Kuhn, 1944)
Geiseltaliellus sp. indet.
Gekkota
?Gen. et sp. indet.
Scincomorpha
? Scincidae
Eolacerta robusta Nöth, 1940
Cordylidae
Gen. et sp. indet.
? Lacertidae
Iguanosauriscus haupti Kuhn, 1944
Anguimorpha
Anguidae
Glyptosaurinae
Placosaurus (Loricotherium, Placotherium) waltheri Weigelt, 1929
Xestops (Placosauroides) abderhaldeni Kuhn, 1940
Xestops (Placosauriops) weigelti Kuhn, 1940
AnguinaeOphisauriscus quadrupes Kuhn, 1940
(? = Propseudopus voigti Kuhn, Parapseudopus hallensis Kuhn, Parapseudopus minor Kuhn,
Ophipseudopus gracilis Kuhn)
Necrosauridae
Eosaniwa koehni Haubold, 1977
"Necrosaurus" (Melanosauroides) giganteus Kuhn, 1940 (=? Melanosauroides eucarinatus Kuhn, 1940)
Gen. et sp. indet.

References: Estes, R. (1983): Handb. Paläoherpet. (Ed.: Wellnhofer, P.), 10 A: 1-249.
Haubold, H. (1977): M.-Luther Univ. Halle, Wiss. Beitr., 1977 (2): 107-112.
Kuhn, O. (1940): Nova Acta Acad. Leop. N.F., 8 (53): 461-486.
Kuhn, O. (1944): Pal. Z., 23: 360-367.
Nöth, O. (1940): Nova Acta Acad. Leop., N.F., 8 (55): 439-460.
Sullivan, R., Keller, T. & Habersetzer, J. (1999): Cour. Forsch.-Inst. Senck.

The ?Namurian tetrapod Caerorhachis bairdi (?Limestone Coal Group, Scottish Midland Valley) is re-diagnosed and re-described, and its affinities are discussed. Caerorhachis is characterised by stout tabulars projecting obliquely rearward; large, broadly crescent-shaped postorbitals; densely denticulated palate and mesial lower jaw surfaces; elongate, subpentagonal choanae, wider posteriorly than anteriorly; narrow, spindle-shaped interpterygoid vacuities; anterior toothless space along maxillary margins; remarkable size difference between vomerine fangs and palatine/ectopterygoid fangs; slender, elongate antero-dorsal process of posterior coronoid; denticulated anterior third of dorsal surface of dentary; broad mesial lamina of splenial; denticulated parasymphysial plate carrying two fangs but no tooth row; high length ratios between head and presacral column, and between femur and puboischiadic plate.

Several cladistic analyses of Palaeozoic tetrapods, based on available morphological data sets as well as on combined information from different data sets, place Caerorhachis either at the base of the anthracosaurs or within this group. When multiple, equally parsimonious solutions are found, the anthracosaur affinities of Caerorhachis are evidenced in at least some of the fundamental trees. Such affinities are generally supported by a large number of informative and, often, highly consistent characters. Alternative phylogenetic placements for this tetrapod (e.g., sister taxon to temnospondyls) are, usually, less well corroborated.

In this paper we attempt to bring together old and new data about ossicle form in marsupials at different stages of development (including adults) to examine patterns of change in the light of current hypotheses on marsupial phylogeny. We have made 3-D reconstructions of the ear ossicles at different ages based on histological series for one or more stages of seven taxa (representing five families) and extracted the ossicles from dozens of macerated skulls. Based on our observations of didelphid marsupials, we conclude that at birth the blastemous ossicles do not form a differentiated joint with the braincase but rather a supportive strut between the lower jaw and the braincase. Pouch young of members of the Peramelidae and Dasyuridae, in contrast to the rod-like condition in adults, show a bicrurate stapes with a sizable obturator foramen. In some members of the Diprotodonta the stapes shows a prominently rounded footplate of the stapes that protrudes into the vestibule of the inner ear, a condition already present in pouch young of these taxa. All marsupials examined to date show a double insertion of the tensor tympani muscle. A stapedial artery was seen traversing the obturator foramen of the stapes in the youngest stages of the didelphids examined. Ontogeny recapitulates phylogeny in several cases: stapes form, timing of development and form of malleolar structures, and presence of a stapedial artery. This research was supported by the Universität Tuebingen Strukturfonds/ Projektförderung 1999 to MRSV and SG and by a Research Trip Grant from DGF to MRSV.

A system of cross-helically-arranged ridges is observed on the endosteal surface of an incomplete but well-preserved pterosaurian long bone from the Romualdo Member of the Santana Formation (Early Cretaceous, ?Albian) of north-east Brazil. This specimen is believed to represent the diaphysis of an ulna of an indeterminate pterodactyloid. Study of the material was by examination of the fractured specimen and by transverse and oblique 30 ?m thin sections.

The endosteal surface is ornamented by several low-relief ridges arranged in a discontinuous cross-helical fashion around the inside of the bone. The opposing ridges trend at approximately 45° to the long axis of the bone, and hence cross each other at approximately 90°. Their length is difficult to determine since they are partly obscured by calcite crystals, but the longest visible ridge runs for 22 mm from its origin to the point where it disappears from view under a crystal. The ridges vary in width from 0 to 1 mm but are mostly between 0.3 < #150; 1 mm wide. However, at one point where two ridges cross, they are up to 2 mm wide. Their height reaches a maximum of approximately 0.3 mm. Where the ridges are discontinuous, an adjacent ridge may appear in an en-echelon arrangement. Some ridges bifurcate in a sub-parallel fashion, resembling a tuning-fork.

Cross bracing, similar to that seen in this bone, is a widespread method of providing stiffness in a variety of man-made structures. It is used in the walls of buildings designed to be earthquake-resistant (shear walls) and in tubes or hoses where cross-helical reinforcement provides resistance to local buckling. Thin-walled tubes such as pterosaur long bones are vulnerable to buckling, and more so with increasing length. The cross-helical system described here may have enabled the long wing bones of large pterosaurs to resist buckling, without adding the extra weight that increasing the thickness of the bone walls would entail.

This probable ulna appears to lack the cross-struts often seen in pterosaurian long bones. We speculate that this might have been a consequence of a well-developed internal air sac.

In this study new information derived from studies of the chondocranium of Recent marsupials and from new fossils from South America is incorporated into a phylogenetic analysis of marsupial relationships at the Family level. The new fossils consist of very well preserved basal argyrolagids that allow to evaluate the homology of the procumbent incisor in this group (i2), as well as the monophyly of Paucituberculata (argyrolagids are sister-group to the shrew-like possums of South America) based on a thorough cladistic analysis (107 characters, 269 character states; 18 taxa and a hypothetical ancestor). Twelve features support the monophyly of Paucituberculata, three unique among Marsupialia (small size of the paraconid, procumbent second lower incisor, and supraoccipital without distinct lambdoid crest resulting in globular form of braincase). New data on the ethmoidal region and adult petrosal anatomy provide additional support for the monophyly of several orders, Eometatheria (contact between caudal and rostral tympanic processes of the petrosal) and is consistent with molecular and previous morphological studies that place the Microbiotheria within an otherwise Australian clade of marsupials.

Synovial joint biomechanics can be explored by creating within a computer parametric models of their articular facets and observing their relative movements during articulation. The condyle/cotyle pair and associated zygapophyses of the cervical vertebrae of two sauropods have been modelled to explore their differing biomechanical designs. Implications for neck stabilisation and bracing will be examined.

The isotopic composition of oxygen in bone apatite is determined by the isotopic composition of the animals body water and the body temperature at the site of bone formation. In the last 10 years this relationship has been exploited to investigate the physiology of extinct vertebrates, most notably, dinosaurs. Heterothermic animals (e.g. small lizards) have wide regional variations in body temperature, so that distal appendages are consistently cooler than core areas. This is reflected in the isotopic composition of bone such that bones from distal limbs are isotopically heavier than bone from core areas. Heterothermic animals should therefore display higher variation in isotopic signals than homeothermic animals. However, application of this method to dinosaurs requires that the isotopic ratio in bone remains unaltered during diagenesis. Based on our current understanding of bone diagenesis, it is very difficult to explain how biogenic isotope ratios could remain unaltered. Instead, most workers assume that bone records a diagenetic isotopic ratio. However, Barrick and co-workers have shown that bones from the dinosaurs Tyrannosaurus and Gigantosaurus show variation in oxygen isotope ratio values between core and peripheral bones that is lower than that expected for heterothermic animals, but nevertheless difficult to explain as an artefact of diagenesis.

We have attempted to explore this apparent contradiction by modelling the effects of diagenetic apatite growth during the diagenesis of dinosaur bone. We will review the isotopic evidence for regional temperature variation in the dinosaurs Tyrannosaurus and Gigantosaurus, and briefly assess the physiological implications

Pelagornithids (Odontopterygia: Pelagornithidae) are extinct marine birds that are most notable for their possession of bony, tooth-like structures in the beak, and an extra joint in the mandibular ramus. They are also notable for their large size, and the wingspan of some genera has been estimated at nearly 6 m. However, the walls of their bones are generally very thin, and this is one reason why their remains are rarely found well-preserved in the fossil record. The taxonomy of the group remains the subject of some debate.

The diverse fossil marine avifauna of a Mio-Pliocene marine bonebed from Bahía Inglesa on the coast of north-central Chile was described at the 1999 SVPCA meeting. This fauna includes pelagornithids but, until now, only two tarsometatarsi and a major carpal digit have been referred to the group. New fossil avian material was recovered from the site by the author in late 1999. The material includes specimens referable to a new large penguin around the size of Aptenodytes fosteri (emperor penguin), and a new small penguin the size of Spheniscus humboldti (humboldt penguin). A new large sulid is also present.

The most spectacular find however, is that of distal portion of a right coracoid. This specimen is similar in overall shape to the coracoid seen in pelicans, except that this fragment is nearly twice the size of the same coracoid portion in Pelecanus occidentalis (brown pelican), and even one and a half times the size of that seen in Diomedea exulans (wandering albatross). This bird was therefore apparently very large, yet the bone walls of this fossil are extremely thin; very much less than 1.0 mm in places. The large size and bone-wall thinness would suggest that this coracoid is probably referable to a pelagornithid, as no other fossil avian of this age is known that would match these characteristics. However, as no three-dimensional pelagornithid coracoid has been described, comparative material is somewhat lacking. Remains referred to the gigantic taxon Pelagornis have be recovered from the coeval Pisco Formation of Peru, some 1000 km to the north. As the size range of the pelagornithid material from the Bahía Inglesa site matches the size range of Pelagornis, the Bahía Inglesa taxon may also be referable to this genus. Nevertheless, this specimen is clearly unusual, and deserves further study.