The origin and early evolutionary history of the dinosaurs is a topic that has recently gone through a period of renewed interest and academic debate. For 130 years, one way of classifying the various dinosaur subgroups persisted as the accepted model, with increasing levels of research in the past quarter-century also providing evidence for the hypothesis that dinosaur origination occurred in the Southern Hemisphere, particularly in South America. It is, after all, from within the Late Triassic strata of countries like Argentina and Brazil that we get some of the very best early dinosaur specimens; many of these specimens are the earliest known representatives of some of the major dinosaur subgroups, such as the theropods and sauropodomorphs. However, some recent analyses have brought about a shift in terms of what is currently accepted and what is now disputed regarding the origin of dinosaurs – the Southern Hemisphere origination hypothesis was questioned (although this was based upon observations and not with quantitative analysis techniques), as has the shape of the dinosaur tree. Responses to the new hypothesis were numerous; many further supported a Southern Hemisphere point of origin. Whilst the interrelationships between the major dinosaur clades remains to be resolved, the current data does seem to comprehensively answer the question of where the dinosaurs first originated. However, it is arguable whether the current data that is being used in such palaeobiogeographical analyses is sufficient to provide an answer to the question of where specifically the dinosaur clade first appeared. This short communication urges a degree of caution about the current consensus and what steps may need to be taken to ensure that more meaningful results are produced in the future. 

The late Pliocene site (MN 16) of Balaruc II (Hérault, France) has provided remains of the following amphibians and reptiles: Chelotriton pliocenicus nov. sp. and Triturus marmoratus (Salamandridae), cf. Rana (Ranidae), cf. Blanus (Amphisbaenidae), cf. Agama (Agamidae),  Gekkonidae indet., Lacerta s.l. (Lacertidae), "Ophisaurus" sp. (Anguidae), Michauxophis occitanus (Aniliidae), Erycinae indet. (Boidae), Elaphe cf. E. longissima and Malpolon sp. (Colubridae), cf. Naja (Elapidae) and Vipera sp. (Viperidae). The salamandrid Chelotriton pliocenicus and the aniliid Michauxophis occitanus constitute, up to now, the only records of these groups in the European Pliocene. The fauna is indicative of a warm, dry
subtropical climate. 

The rodent-fauna (Cricetidae and Gliridae) recently found at Castell de Barbera (Spain) is similar to those from the other locslities of the Valles - Penedes - Can Ponsic 1 and Can Llobateres - : same composition and similar evolutionary level of the different species. On the other hand this fauna is different from those of Upper Vindobonian and Vallesian localities of the Calatayud - Teruel area. Castell de Barbera has an intermediate chronological position between the localities of Anwil (Switzerland) and Can Ponsic 1. It is still not possible to validate or invalidate the initial attribution based on absence of Hipparion of Castell de Barbera to the Upper Vindobonian. 

The remains of Ruminantia are very rare at Montredon. No specific determination was possible. We have only one Micromeryx, one small cervid, one tragocere and one (?) gazella. The faunal spectrum is in good correlation with the general retreat of the cervids in the European upper Miocene, but in contrast it is not convenient for the bovids, which are in expansion at the same time. For them, we have to invoke the local ecological conditions.
  

Extensive sampling of the Siwalik deposits of the Potwar Plateau of northem Pakistan and from the Zinda Pir dome of central Pakistan has produced a fossil record of Miocene ctenodactylids that can be correlated with the paleomagnetic time scale. The early Miocene Prosayimys flynni (n. gen., n. sp.) is recognized as the first ctenodactylid in the Indian subcontinent. Prosayimys is ancestral to Sayimys. From the late early Miocene to the early late Miocene, there is an anagenetic succession of three species of Sayimys: S. cf. S. intermedius, S. sivalensis, and S. chinjiensis (n. sp.). Sayimys chinjiensis gave rise to the late late Miocene S. perplexus. A second lineage is represented by Sayimys minor, S. sp. A, and S. sp. B. 

Remarkable association of a small infraorbital foramen, similar to that in recent Heterocephalus, and of a strong muscular print on the dorsal anterior part of the zygomatic plate and on the premaxillary. Several anatomical structures to be compared with those of Heterocephalus suggest relationships with this genus. Richardus supports the ancestrality of the hystricomorph character in the bathyergids 

     The Faunas of Rodents from seven north-african fossiliferous beds distributed from the Middle up to the Uppest Miocene are studied. One genus, seventeen species, one subspecies described are new.
       A detailed description is given of the evolution of the numerous specific lines, systematic groups and communities. The evidence of the strong endemism of the North African faunas of that time compared with those of Europe as well as of Tropical Africa is clearly shown. Special relationships with Asia clearly also appear, mostly in the Middle Miocene and the beginning of the Upper Miocene.
       Using the specific lines with a biostratigraphic purpose gives the opportunity to establish a biochronological scale for the continental formations of the Maghreb. This scale is calibrated by a few absolute datations. These datations, as well as the stratigraphical study of several fossiliferous localities have given the possibility to establish precise correlations with the corresponding scales of Europe and of Tropical Africa, as well as with the marine formations of the Neogene of occidental Mediterranean sea.
       The paleoclimatic data connected with this period in North Africa are explained and the contribution of the micromammals is discussed. 

This study describes four taxa of Gliridae from the Oligocene mammal locality Gröben 3: Gliravus tenuis BAI-ILO, 1975, Bransatoglis micio (MISONNE, 1957), B. planus (BAHLO, 1975) and B. heissigi n. sp. Gliravus tenuis from Gröben 3 is somewhat more advanced than the type population found in Heimersheim. This confirms previous research suggesting that Gröben 3 should be dated earlier than Heimersheim (MP 24). The first documented occurrence of B. mício around level MP 24 was found in Gröben 3. An abundance of tooth material from B. planus in Gröben 3 makes it possible, for the first time, to observe evolutionary stages within this species from MP 21 until MP 28. B. heissigi n. sp. is restricted to level MP 24. This species is located between B. mísonnei (MP 20 - 23) and Microdyromys praemurinus (MP 25 - 28). Within the lineage Bransatoglis bahloi - B. misonnei - B. heissigi, a decrease in size is noticeable.

  

About the early radiation of Rodents, we have now from the early tertiary of Asia, a new fossil record, and we can do new interpretations. First the problem of the origin of Rodents is studied : considered as a sister group of Lagomorpha, it is possible to find their ancestors between the Mixodontia. Second the new facts about the origin of modern groups of Rodents are reviewed. A general scheme of this diversification can be proposed. 

The faunal list of the mammals collected at the locality of Aumelas (Hérault, France) is revised. For the first
time this Middle Eocene locality is precisely settled in the european chronological scale of "niveaux repères", between the levels of Bouxwiller and Egerkingen, in Uppermost Lutetian.
A new Dichobunid from the site is described : Aumelasia gabineaudi n. g., n. sp. This new genus has primitive characters. and it may be in the descent of the Lower Eocene Protodichobune. 

A new Propalaeotherium species, clearly distinct from the genus Eurohippus, is described. It is characterized by having a similar size as P. voigti from the German Geiseltal localities (MP 11 to MP 13 reference-level), but differs in several features suggesting a slighty more derived morphology. It presents indeed less brachyodont crowns with less prominent and less elevated cingula, slightly larger relative surface of premolars, and a more marked metaconid splitting on cheek teeth. This new species is unknown from other European localities except the nearby Saint-Martin de Londres locality which has been considered older than the MP 13 level. 

Three new fossiliferous localities, two of karstic origin, Castelnou 3 and Font Estramar, respectively Late Upper Miocene and Lower Pliocene, and one of lacustrine origin, Thuir, Lower Pliocene, add data about the transition between Miocene and Pliocene faunas of rodents in southern France. An unexpected association of taxa was present in the late Upper Miocene, including between others, Myocricetodon, Hispanomys, Ruscinomys, Cricetus barrierei, Promimomys and a new species of Stephanomys, S. dubari nov. sp. Myocricetodon is still known in the Lower Pliocene. It is shown that the large field-mice known since the Late Upper Miocene belong to two different lineages, on one side, A. jeanteti, on the other side, A. gudrunae followed by A. gorafensis. Biochronological and biogeographical implications are discussed. 

A fragmentary mandible and maxilla of a small sized Agriotherium of a young individual discovered from a Pliocene fissure filling in Xiaoxian county (Anhuei Province, China) are described. Judging from the morphology of the dentition and its dimensions the new material can be identified as Agriotherium inlermedium (STACH l957). Hendey's proposition (1980) that the Agriotherium species are derived from Indarctos is reconsídered on the basis of the new documents. As a result of a more general phylogenetic discussion it can be stated, that: 1. the supposed size increase as well as other trends, leading from Indarctos to Agriotherium are untenable ; 2. there are no positive indications to assume a phylogenetic transition of these two genera. 3. there are no real arguments in favor of an adaptational reversal in the evolution of Agriotherium. Hence, many features of that genus supposed by Hendey to be derived are plesiomorphic ; 4. regardless of the previous points it is methodologícally impossible to establish direct ancestor - descendant relationships between Indarctos and Agriotherium species, as Hendey did. Based on the data available and especially on the characters of the new material from China it is more likely that Agriotherium and Indarctos are two genera which developed independently. While advanced Agriotherium species, e.g. A. africanum, resemble in some respects Indarctos by adaptational analogies, more primitive species, e.g. Agriotherium intermedium, are quite dissimilar to lndarctos. While Indarctos might be derived from an Ursavus like forerunner, Agriotherium has its roots more likely somewhere in between Ursavus and the Hemicyon-group. 

Extensive collecting in previously known and new Middle Eocene rodent localities in the Subathu Group of the Rajauri and Reasi districts, Jammu and Kashmir (northwest Himalaya, India) has yielded over 500 isolated cheek teeth, numerous incisors and cheek tooth fragments, and two mandibular fragments with M/1-M/3. An analysis of this additional material and a restudy of that reported earlier from the Metka (Rajauri) area has revealed the presence of diverse Middle Eocene ctenodactyloid rodents in India. The assemblage comprises six genera and twelve species, viz.., Bírbalomys woodi, B. ibrahimshahi, B. sondaari, Basalomys vandermeuleni, B. ijlsti, B. lavocati, Chapattimys wilsoni, C. debruijni, Gumbatomys asifi, cf. Advenimus bohlini, cf. Petrokoslovia sp. indet. 1 and cf. Petrokoslovia sp. indet. 2. Most species of this assemblage are endemic to the Indian subcontinent and are referred to the Family Chapattimyidae. However, at least three taxa, viz.., cf. Advenimus bohlini, cf. Petrokoslovia sp.indet. 1 and cf. Pezrokoslovia sp. indet. 2 show close affinities with their Central and Eastern Asiatic contemporaries and are attributed to the Family Yuomyidae. The dentitions of most of the Middle Eocene rodents from India are described here in better detail thus providing more precise characterization than was available earlier. The taxonomie status of Basalomys, formerly a subgenus of Birbalomys has been raised to that of a genus. Basalomys vandermeuleni is here designated as the type species of Basalomys in place of B. ijlsti. The rodent assemblage from the Subathu Group is specifically similar to that from the coeval Kuldana Formation of Pakistan. The absence of Birbalomys ibrahimshahi and cf. Advenimus bohlini in Pakistan is related to sampling bias. The identifications of the Early Eocene rodents from Barbara Banda, Pakistan have been reexamined and the familial assignments of some of the Early and Middle Eocene rodents from Central and Eastern Asia have been discussed and reviewed in the light of recent discovery of early rodents in Mongolia.

  

Prolagus sardus is the last representative of the diverse lineages of European endemic ochotonids. It is also the most abundant in the collections. The previous studies made of this species have established rather well its dental morphology, its phylogenetic position, its geographic and temporal distribution, and its intraspecific individual variation. On the other hand, no osteologic study has fully utilized the superb material from Corsica and Sardinia  collected by Forsyth Major.
Nearly all of the parts of the skeleton are represented in this material; they are here described and figured. Comparisons are made with Ochotona, the only surviving genus of the family, as well as with the living leporids, in particular Romerolagus, Oryctolagus and Lepus. A brief examination of the dentition reveals some particular characters of the incisors. The osteologic study allows limited interpretations to be advanced concerning the posture, mastication. locomotion and some other adaptive features of P. sardus.
P. sardus appears as an incontestable ochotonid, but it differs from Ochotona by some characters which are found in leporids. Certain of the characters are here judged primitive for lagomorphs. The genus Ochotona therefore can no longer be considered as the image of a primitive lagomorph, because in spite of the lack of cursorial adaptations which differentiate it from leporids, it presents other specializations which are common to it alone. 

Stratigraphic studies in the Aktau Mountains bordering the Dzhungarian Alatau Range in southeastern Kazakhstan have included mapping of Tertiary lithostratigraphic units, documentation of fossiliferous deposits, correlation of sections, etc. These investigations have led in turn to revised interpretation of the Tertiary geology of the area. The Tertiary sequence in the Aktau Mountains is represented by three lithostratigraphic units (in ascending order): (1) the middle Eocene Akbulak Formation; (2) the Oligocene Aktau Formation with a lower member including white quartz sands that contain fossil mammals, and an upper member including red-colored clays and sandstones, brick red clays, an anhydrite and gypsum clayey horizon, and bright brown-red clays; and (3) the upper Oligocene-Miocene Chul'adyr Formation with a lower member of greenish and yellowish conglomerates and gritstones, a middle member including grayish and yellowish sands and gritstones, and an upper member including brown and red clays and carbonate- and anhydrite-rich clays. The Aktau and Chul”adyr Formations represent separate cycles of sedimentation. Mammalian biostratigraphy and biochronology of the three vertebrate faunas in Aktau Mountains are reviewed. The mammalian fauna from white sands of the lower Aktau Formation is small but includes Ardynia and is thought to be early Oligocene in age. The mammalian fauna from conglomerates and gritstones of the lower member of the Chul”adyr Formation is also small but includes Paraceratherium and is thought to be late Oligocene in age. The mammalian fauna from sands of the middle member of the Chul'adyr Formation is extensive, with micro- and macrofauna attributed to Neogene mammal zones MN4 to MN 6, indicating a latest early Miocene to earliest middle Miocene age (Orleanian-Astaracian). Most genera of middle Chul”adyr mammals are known from the middle Miocene Shanwang faunas of China and from the Castelnau-d”Arbieu faunal assemblage (MN4-MN6) of southwestern France. 

Two new species, Omanodon minor n. g., n. sp. and Shizarodon dhofarensis n. g., n. sp., known from fifteen isolated teeth, are described here as the first adapiform primates (?Anchomomyini) recognizable to date in the Taqah material (early Oligocene of Sultanate of Oman).

Omanodon minor n. g., n. sp. displays special morphological similarity to the adapid tribe Anchomomyini from the Eocene of Europe, and especially to the Anchomomys lineage. Resemblances with the extant lemurifonn Microcebus are also noticeable and could be regarded as supporting Schwartz & Tattersall (1983) hypothesis of special relationships between the anchomomyine adapids and the cheirogaleid lemuriformes. However, these morphological affmities can be interpreted, altematively, as the results of parallelisms: important differences in upper molars indicate that the resemblances of cheirogaleids and Omanodon minor n. g., n. sp. are indeed probably due to parallelisms. Phyletic relationship of O. minor n. g., n. sp. to Anchomomyini is finally the most likely hypothesis.

Shizarodon dhofarensis n. g., n. sp., although much more poorly known, is closely related to Omanodon minor n. g., n. sp., at least at a familial level. The general morphology of this species suggests
also a close link with adapid Anchomomyini, although precise relationships within this tribe remain obscure. Interesting resemblances of Shizarodon dhofarensis n. g., n. sp. to Djebelemur martinezi lower molars (early Eocene of Tunisia) are also noticeable. These resemblances are even stronger than those betwen Omanodon minor and Djebelemur martinezi. However the very bunodont upper molars referred to D. martinezi are unusual for adapids, and there are moreover some notable differences in their lower molars. Thus resemblances in Djebelemur and Shizarodon are probably due to paralellisms.

Because of the fragmentary nature of the material and of possible parallelisms, the systematic position of Omanodon and Shizarodon within adapiformes cannot however yet be established definitively. 

 A new genus of hystricognath rodent with two new species, Soriamys gaimanensis and Soriamys ganganensis, from the Colhuehuapian Age (Early Miocene), Sarmiento Formation, of Patagonia is described. The first species comes from the south barranca of the valley of Rio Chubut, near Gaiman locality (Chubut Province). It is known through a great number of dental remains in different stages of wear. The teeth are protohypsodont, with cement in the principal valleys. P4 are simpler, more oval inoutline and without a differentiated hypocone-hypoflexus. Upper molars are pentalophodont in early stages of wear and become bilobated in middle and advanced stages; M3 have a temporary third posterior lobe due to the maintenance of the braquiflexus on the posterior wall of the tooth. Lower teeth have a completely asymrnetrical pattern in relation to the uppers. The molars are trilophodont, with only one complex crest in the trigonid composed of the fusion of the anterolophid and mesolophid. The dp4 have a derived pentalophodont pattern due to the loss or fusion of the mesolophid and the development of an accessory transverse crest between the anterolophid and metalophid. The second species is known through a complete skull and jaw and other skull fragments with the dentition, proceeding from Pampa de Gan Gan, Chubut province. Respect to the first species, the teeth are higher crowned, with an earlier occlusal simplification and a third posterior lobe of M3 more developed and persistent. The skull and jaws show many chinchilloid characters, such as jugal bone with an ascending process, concave palate, very prominent dorsal shelf of the masseteric fossa, nasolachrymal duct opened laterally on the maxillary and very developed lateral mandibular fossa. Moreover, Soriamys is closely related to Cephalomys by sharing a similar asymmetric dental pattern and other dental and mandibular characters. These two genera constitute a natural group, the Cephalomyidae, with peculiar dental characters, like the asymmetric pattem of the upper and lower teeth; Cephalomyopsis, and probably Litadontomys, can be considered part of this group. Scotamys and Perimys constitute a distinct lineage (the Neopiblemidae or Perimyidae), more closely related to the chinchillids. Many characters shared by cephalomyids, eocardiids and caviids suggest a closer affinity between the Chinchilloidea and the Cavioiidea as a whole. Abrocoma shows also an asymmetric dental pattern and other chinchilloid features that suggest some degree of relationship with the cephalomyids, still not well determined. 

The new fauna of Collet Redon (Bouches-du-Rhône, France) is dated by three rodents: Megacricetodon aff. bavaricus, Democricetodon affinis mutilus and Peridyromys cf. hamadryas. They correlate this locality with Oggenhof and Ohningen in Bavaria (Western Germany). As the radiometric age of Ohningen is estimated between 14 and 13 M.Y., these three localities are of Serravallian age. This datation brings a complete readjusment of the stratigraphy of the section of Collet Redon formerly described by Collot and Combaluzier. The marine deposits with underly the continental formation with the mammal fauna, are Burdigalian. The angular unconformity between the marine and the continental deposits gives evidence of an episode of emersion on the margin of a sedimentary basin, with deformation and erosion. Owing to the newly discovered fauna, this geodynamical event is clearly settled within the regional geographical and chronological context. Lacustrine and continental deposits of such an age were up to now unsuspected in this area. 

Description of four new rodents from a recently discovered locality at Montalban. Theridomys crusafonti nov. sp. is considered as the ancestry of T. Iembronicus. Theridomys varian: nov. sp. includes «Theridomys» morphotypes and «Blainvilllimys» morphotypes; it could be ancestral to B. blainvillei. Pseudoltinomys nanus nov. sp. represents a new lineage paralleling in evolution that of P. gaillardi (which is equally found at Montalban). Pseudocricetodon montalbanensis nov. gen., nov. sp. designates a lineage of very small Cricetidae accompanying Eucricetodon. With these well defined new species and six others present in the locality, Montalban appears as the best faunal reference point within the biochronologic zone of La Sauvetat.
As an annex, discussion of two rodent specimens from the classic localíty of Tárrega, close in age to that of Montalban.