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Great Heaping Gobs of New Papers

That should be read with a Scottish brogue, by the way...

First, a batch from _Cretaceous Research_:


Matsukawa, M., Lockley, M., and Li, J. 2006. Cretaceous terrestrial biotas of East Asia, with special reference to dinosaur-dominated ichnofaunas: towards a synthesis. Cretaceous Research 27(1):3-21. doi: 10.1016/j.cretres.2005.10.009.

ABSTRACT: This paper represents an "editorial" introduction to this issue, which is one of two special issues of Cretaceous Research on the geology and paleontology of East Asia. This paper makes special reference to the results of joint Japanese, Chinese, and North American expeditions that investigated more than 70 fossil footprint sites and other fossiliferous localities in China, Japan, Korea, Laos, Mongolia, and Thailand. More than 50 of the track sites are considered Cretaceous in age, though in some cases dating is uncertain. We herein present summaries of selected important sites not previously described in detail based on new maps, tracings, and replicas of representative type specimens and related materials that have been assembled in accessible reference collections. Other sites are described in detail elsewhere in this issue and are placed in broader paleoenvironmental context in conjunction with papers that deal with floras, invertebrate and vertebrate body fossils, paleoecosystem reconstruction, and their stratigraphic, sedimentological, and tectonic settings in the second of the two special issues.
Preliminary syntheses suggest that Cretaceous vertebrate ichnofaunas of East Asia contain various distinctive elements that are neither typical nor common in other regions. These include an abundance and significant diversity of bird tracks, some with web impressions, various small theropod tracks including diminutive examples (Grallator and Minisauripus) with foot lengths of 2.0-3.0 cm, probable small dromeosaurid tracks (Velociraptorichnus), probable coelurosaurid tracks with bilobed heel impressions (Siampodus), and various small ornithopod tracks that resemble Anomoepus. Giant pterosaur tracks (Haenamichnus) are also unique to this area. A review of the ichnotaxonomy generously accepts about eleven valid ichnogenera of dinosaurs, two of pterosaurs, and nine of birds. At least ten other ichnogenera are dubious and among these several have already been rejected.
A preliminary overview of these ichnotaxa in broader context suggests that the dominance of bird and theropod ichnotaxa is a valid reflection of a corresponding dominance of birds and theropod body-fossil taxa. We also note partitioning of ichnofaunas into saurischian-dominated assemblages from low, tropical latitudes and semi-arid, inland basin paleoenvironments, and ornithopod-rich assemblages from higher, more temperate latitudes and humid, coastal paleoenvironments.

Chen, P.-J., Li, J., Matsukawa, M., Zhang, H., Wang, Q., and Lockley, M.G. 2006. Geological ages of dinosaur-track-bearing formations in China. Cretaceous Research 27(1):22-32. doi: 10.1016/j.cretres.2005.10.008.

ABSTRACT: In China more than 30 forms of dinosaur tracks at about 50 localities distributed in 16 provinces have been reported. These fossil footprints have been found in 25 Upper Triassic to Upper Cretaceous formations. They are the Xujiahe Formation (Upper Triassic), Zhenzhuchong and Ziliujing formations (Lower Jurassic), Xintiangou and Lower Shaximiao formations (Middle Jurassic), Penglaizhen Formation (Upper Jurassic), and Jiaguan and Daergun formations (Upper Cretaceous) in the Sichuan Basin; the Fengjiahe Formation (Lower Jurassic) and Jiangdihe Formation (Upper Cretaceous) in the central Yunnan Basin; the Zhiluo Formation (Middle Jurassic) and Fengjiashan Formation (Lower Cretaceous) in Shaanxi Province; the Jingchuan Formation (Lower Cretaceous) in Inner Mongolia; the Houcheng Formation (Upper Jurassic) and Jiufotang Formation (Lower Cretaceous) in northern Hebei; the Tuchengzi Formation (Upper Jurassic) and Fuxin Formation (Lower Cretaceous) in western Liaoning; the Laiyang Formation (Lower Cretaceous) in the Shandong Peninsula; the Tongfosi Formation (Cretaceous) in eastern Jilin Province; the Hekou Group (Lower Cretaceous) in Gansu; and the Xiaodong, Qiyunshan, and Nanxiong formations (Upper Cretaceous) in Hunan, Anhui, and Guangdong provinces, respectively. The invertebrate and vertebrate fossils including tetrapod footprints reported from some of these formations are outlined and their biostratigraphic significance and utility for correlation are discussed.

Lockley, M., Matsukawa, M., Ohira, H., Li, J., Wright, J., White, D., and Chen, P. 2006. Bird tracks from Liaoning Province, China: new insights into avian evolution during the Jurassic-Cretaceous transition. Cretaceous Research 27(1):33-43. doi: 10.1016/j.cretres.2005.10.007.

ABSTRACT: Tracks of shorebird-like species from a small outcrop in the upper part of the Tuchengzi Formation at Kangjiatun, in the Beipiao area, Liaoning Province, may be the oldest bird tracks known from China. Formerly considered Late Jurassic in age, new fission track dates give an age of 145.9 Ma for ash beds associated with dinosaur track-bearing beds from the middle part of the Tuchengzi Formation outcrops at a nearby locality. Thus, the age appears to be close to the Jurassic-Cretaceous (Tithonian-Berriasian) boundary. The precise age of the bird track-bearing beds has not been determined, but is unlikely to be younger than about 139 Ma, based on dates for the upper part of the Tuchengzi Formation. Thus, the bird tracks, like the Tuchengzi ichnofauna in general, predate the famous Yixian Formation, which has produced a different avifauna.
The most distinctive tracks are here named Pullornipes aureus ichnosp. nov. and are tentatively assigned to the ichnofamily Koreanornipodidae. Other tracks from the same site appear to represent different ichnotaxa and therefore indicate the potential to find diverse avian ichnofaunas at this time. This record supports the evidence that East Asian avian ichnofaunas are the most diverse known during the Early Cretaceous.

Zhang, J., Li, D., Li, M., Lockley, M.G., and Bai, Z. 2006. Diverse dinosaur-, pterosaur-, and bird-track assemblages from the Hakou Formation, Lower Cretaceous of Gansu Province, northwest China. Cretaceous Research 27(1):44-55. doi: 10.1016/j.cretres.2005.10.006.

ABSTRACT: Diverse and well-preserved assemblages of dinosaur (theropod, sauropod and ornithopod), pterosaur, and bird tracks from the Hekou Formation (Lower Cretaceous) in the Yellow River (Huang He) valley represent the first significant fossil footprint discoveries in Gansu Province, China. However, the sites are large, visually spectacular, and well-exposed thanks to labor-intensive hand excavation. The sites have the potential for development as educational and tourist destinations. These sites have become one of the National Geoparks in China.
Dinosaur tracks include at least two theropod morphotypes that range in size from about 5 to >30 cm in length. Wide-gauge sauropod tracks (Brontopodus) range in size from 25 to 90 cm (pes length) and are the best-preserved examples known from China, with clear claw impressions. One trackway suggests an accelerating/running individual. Parallel ornithopod trackways indicate gregarious behavior. An enigmatic trackway may be a manus-only ornithopod trackway.
A pterosaur trackway (cf. Pteraichnus), the first reported from China, consists of 24 consecutive footprints, and is the longest, well-preserved trackway on record. Bird tracks (cf. Aquatilavipes) are also very well preserved.
The tracks occur at multiple stratigraphic levels in fluvio-lacustrine sequences of paleosol mudstones and sandstones with mud cracks and wave ripple marks. A minimum ichnodiversity of eight, the highest reported from the Cretaceous of China, is estimated. The saurischian component (theropods and sauropods) compares well with Inner Mongolia ichnofaunas from the Jing Chuan Formation. However, the co-occurrence of ornithopod and sauropod tracks is rare in Asia and globally, and compares with assemblages from South Korea, a similar Cretaceous paleolatitude (ca. 30°).

Kim, J.Y., Kim, S.H., Kim, K.S., and Lockley, M. 2006. The oldest record of webbed bird and pterosaur tracks from South Korea (Cretaceous Haman Formation, Changseon and Sinsu Islands): More evidence of high avian diversity in East Asia. Cretaceous Research 27(1):56-69. doi: 10.1016/j.cretres.2005.10.005.

ABSTRACT: Tracks of web-footed birds and pterosaurs from the Lower Cretaceous (Aptian-Albian) Haman Formation of Changseon and Sinsu Islands, respectively (southern coast of Korea), represent the oldest records for these footprint types in Asia. The morphology of the bird tracks, with prominent posteriorly directed hallux impression, semi-palmate web, and small ratio of length to width is similar to Hwangsanipes choughi from the Upper Cretaceous (Cenomanian) Uhangri Formation. However, they about 20-25% smaller, and therefore much closer to the size of North American Ignotornis (size difference less than 10%). The development of the web appears intermediate in size between Hwangsanipes and Ignotornis. This leads us to infer a new ichnotaxon herein named Ignotornis yangi. This is the first Asian report of a named bird track similar to the type material of Ignotornis from North America.
Pterosaur tracks consist predominantly of clear impressions of tridactyl mani (length 9-13 cm) characterized by strongly asymmetric digit impressions that outnumber less-clear elongated pes traces by a ratio of about 10 to 1. Clusters of short digit impressions or parallel to subparallel scrape marks indicate incomplete pes traces probably made by swimming animals. The pterosaur tracks, here provisionally identified as Pteraichnus, represent the first record of this ichnogenus from Korea. The track maker represents a species quite different from the giant track maker represented by the ichnogenus Haenamichnus from the Cenomanian Uhangri Formation, but it is similar to recent reports of Pteraichnus-like forms from the Lower Cretaceous of China.
These new records shed light on patterns of bird-track diversity and abundance in the "mid" Cretaceous of Korea (Aptian-Cenomanian) and show that at least two quite distinct pterosaurian species existed during this time span with at least six distinct species of track-making birds. When combined with additional reports of bird track ichnotaxa from China, the picture emerges of a remarkably diverse Lower Cretaceous avifauna. Such diversity is consistent with the skeletal record for this region, though the types of birds represented by tracks are "shorebird-like" and therefore distinct from the skeletal avifauna, which consist of birds of the perching type.
The ability of tracks to record whole foot morphology including details of web and hallux configuration allows for fine discrimination of foot morphology and comparison with web-footed tracks from other regions and geologic time periods. As is the case with modern shore birds, Cretaceous tracks were probably mostly made by adults whose foot size as well as shape is probably indicative of the identity of the track maker at low taxonomic levels.

Lockley, M.G., Houck, K., Yang, S.-Y., Matsukawa, M., and Lim, S.-K. 2006. Dinosaur-dominated footprint assemblages from the Cretaceous Jindong Formation, Hallyo Haesang National Park area, Goseong County, South Korea: Evidence and implications. Cretaceous Research 27(1):70-101. doi: 10.1016/j.cretres.2005.10.010.

ABSTRACT: The track-rich Cretaceous Jindong Formation comprises part of an intra-arc basin, fluvio-lacustrine succession that represents a late stage in the evolution of the Kyongsang Basin. This formation is replete with track-bearing levels indicating the activity of many generations of dinosaurs and birds. The track-rich beds occur in the upper part of the Hayang Group (Kyongsang Supergroup), which also contains other, underlying dinosaur-track-bearing formations. However the Jindong Formation and underlying formations have produced few age-diagnostic body fossils. Altered volcaniclastic sediments such as are found the Jindong Formation complicate interpretation of the age of the tracks as discussed in the accompanying companion paper. Nonetheless such settings provided near optimal conditions for the formation and preservation of abundant track assemblages (ichnofaunas), and the Jindong Formation has become an ichnological "cause celebre" producing impressive statistics on the number of track-bearing sites, number of track-bearing levels and number of measured trackways. These data allow various inferences about certain aspects of the population structure, behavior and distribution of the dinosaurian track makers in these dinosaur-dominated paleocommunities.
The Jindong Formation and underlying Haman Formation have also yielded many bird tracks. The complete lack of avian body fossils in Korea and the rarity of dinosaur skeletal remains means that the footprint record currently provides the vast majority of the Mesozoic vertebrate evidence available for the entire Korean peninsula. Thus, the tracks represent a highly significant addition to the national paleontological heritage of Korea, as well as being a very important component of the East Asian and global footprint records. Detailed studies of a 100-200-m-thick succession at the Sangjok Dinosaur Tracksite National Monument in the Hallyo Haesang National Park area in Kosong County reveal an average of about two track-bearing levels per meter, making it one of the richest track-bearing sections on record and providing evidence of the activity of hundreds of individuals. Many other track sites are found locally in the Jindong Formation in Kosong County (about 500 km2) including one described herein from near Gohyeon village where the Jindong Formation type section is situated. Other track sites can be traced laterally over larger distances within the Gyeongsang Basin. The composition of ichnofaunas throughout this region appears remarkably consistent.
The Jindong Formation is one of the few localities where sauropod, ornithopod, and bird tracks all occur in abundance, probably due to latitudinal/climatic controls. The sauropod tracks, which include wide-gauge forms allied to Brontopodus, form the largest brontosaur trackway sample yet reported but are characterized by a high proportion of small individuals. Such unusual size-frequency distributions raise interesting ecological and taphonomic questions about the biasing of the body fossil record towards large individuals by various physical (preservational) or biological/ ecological controls.
The most abundant dinosaur trackways are those of iguanodontids (cf. Caririchnium or Iguanodontipus) that often traveled in herds. By contrast, sauropod tracks show little or no evidence of gregarious behavior and rarely occur on the same bedding planes as ornithopod trackways. This suggests a pattern of mutual exclusion or geological segregation between these two herbivore groups, which indicates that they probably frequented the area at different times. Sauropod and ornithopod track size-frequency distributions are also fundamentally different, suggesting that the ornithopods were mainly sub-adults and adults, whereas the sauropods were predominantly juveniles. Theropod tracks are uncommon suggesting a low predator:prey ratio of 1:20.
Bird tracks including the large ichnospecies Jindongornipes kimi, an intermediate-sized form, Goseongornipes markjonesi ichnosp. and ichnogen. nov., and a small ichnospecies Koreanaornis hamanensis occur at several dozen stratigraphic levels in association with nematode trails (Cochlichnus) and other invertebrate traces. These three ichnospecies are assigned to the respective ichnofamilies Koreanornipodidae ichnofam. nov., Ignotornidae, and Jindongornipodidae ichnofam. nov. All these avian footprints are typical of bird track assemblages in lake shoreline deposits, and indicate the activity of many generations of waders or shorebirds. We also recognize other, much less common, small footprint types tentatively attributed to a perching bird or a diminutive theropod. Collectively the bird tracks indicate the considerable potential of avian ichnites to provide insight into avian paleoecology at an early stage in the evolution of Class Aves.

Houck, K.J., and Lockley, M.G. 2006. Life in an active volcanic arc: petrology and sedimentology of dinosaur track beds in the Jindong Formation (Cretaceous), Gyeongsang Basin, South Korea. Cretaceous Research 27(1):102-122. doi: 10.1016/j.cretres.2005.10.004.

ABSTRACT: The Jindong Formation was deposited as a thick succession of fine-grained volcaniclastic sediments in a rapidly subsiding intra-arc basin. These sediments contain abundant dinosaur and bird tracks that occur on many bedding planes throughout the approximately 110 m of stratigraphic section measured for this study. The main lithologies in the Jindong Formation are ash-rich mudstone, siltstone, and very fine sandstone. Minor lithologies are coarser sandstone, conglomerate, carbonates, and ash tuff. The sandstones are feldspathic and lithic arenites and wackes. They contain plutonic feldspars, volcanic rock fragments, volcanic ash, and a variety of quartz types. All lithologies show evidence of extensive post-depositional alteration, including devitrification and replacement of detrital grains by authigenic minerals. The alterations are typical of burial metamorphism with high heat flow. Sediments of the Jindong Formation can be grouped into three facies associations. Association 1 (proximal) comprises 16% of the measured sections. It consists of various types of bedded, cross-bedded, laminated, and ripple cross-laminated sandstone and minor conglomerate. These are interpreted as fluvial or distributary channel and proximal lake deposits. Association 2 (medial) comprises 53% of the measured sections. It consists mainly of heterolithic couplets of very fine sandstone and mudstone that are mm to dm thick. They contain graded bedding, laminations, current ripples, wave ripples, and mud cracks, and are interpreted as lacustrine hyperpycnal flow deposits. Association 3 (distal) comprises 31% of the measured sections. It consists mainly of bedded shale, mudstone, and siltstone. These are interpreted as distal lake deposits. Associations 2 and 3 contain minor carbonates, which are interpreted as lacustrine and/or diagenetic in origin, and minor tuffs, which are interpreted as tephra. Small wave ripples, dinosaur tracks, invertebrate burrows, and mud cracks are common throughout the measured sections; thus the Jindong lakes are inferred to have been shallow and ephemeral in nature. Wave ripple-crest orientations are consistently WNW-ESE, indicating a prevailing wind direction from the NNE or SSW. Because the sediments are mostly fine-grained and the ash beds thin, the study area is inferred to have been in a distal lowland setting, at least tens of km away from erupting volcanoes. Paleoclimate reconstructions suggest that the study area had a seasonal climate with wet summers and dry winters. Cooler, wetter conditions are thought to have prevailed to the north, and warmer, drier conditions to the south. Modern volcanic arc environments with seasonal and/or humid climates are characterized by rapid aggradation of ashy sediment that fills drainages and causes widespread flooding. This style of sedimentation accounts for the facies found in the Jindong Formation, as well as the many bedding-plane exposures of tracks. The unusual occurrence of both sauropod and ornithopod tracks in the Jindong sections may be the result of a climate boundary that existed in the area at the time. Facies analysis of track types indicates that various track makers had the same environmental preferences, and facies association 2 contains the greatest number of tracks of all types. It is inferred that the tendency for only one track type to occur on a given bedding plane is the result of different types of animals visiting the study area at different times, rather than differing environmental preferences. The Jindong Formation contains an abundance of subaqueously deposited facies, an abundance of tracks, and many track levels that were wet when animals were walking on them. These features are not consistent with previous interpretations of aridity during Jindong time.

Huh, M., Paik, I.S., Lockley, M.G., Hwang, K.G., Kim, B.S., and Kwak, S.K. 2006. Well-preserved theropod tracks from the Upper Cretaceous of Hwasun County, southwestern South Korea, and their paleobiological implications. Cretaceous Research 27(1):123-138. doi: 10.1016/j.cretres.2005.10.003.

ABSTRACT: Abundant dinosaur fossils including footprints, eggs and nests, teeth, and bones have been found from the Cretaceous nonmarine deposits of Korea. Among them, dinosaur tracks are the most distinctive, and some tracksites are among the most famous in the world. Approximately 1500 well-preserved dinosaur footprints, including more than 60 trackways, have been excavated from the Cretaceous Neungju Group in a quarry in Seoyu-ri, Hwasun County, Jeollanam-do, South Korea. Unlike other dinosaur fossil sites in South Korea, most of the tracks found in the area belong to theropods, especially small-sized theropods. The tracks show significant variation in size, morphology, and divarication. On the basis of morphology and size, the theropod tracks have been classified into three types. The first type is characterized by its small size, wide divarication, and slender digits, which can be more closely compared to Magnoavipes. The second type shows slightly thicker digits than the first one and narrow toe impressions and is similar to Ornithomimipus or Xiangxipus. The footprints of the third type belong to large theropods and display distinct sharp claw impressions. The calculated body sizes of the dinosaurs vary between small theropods with an estimated hip height of 68.4-194.5 cm, and large theropods with a maximum estimated hip height of 260.9 cm. The variety of morphotypes and sizes of the footprints and the calculated body sizes indicate that different theropods with various gaits inhabited in the study area during the Cretaceous. On the basis of the speed and gait analyses, it is inferred that the small theropods in the area were trotting, while the large theropods were walking slowly. The fossil site also shows diverse gaits with unusual walking patterns and postures in some tracks.

Lockley, M.G., Matsukawa, M., Sato, Y., Polahan, M., and Daorerk, V. 2006. A distinctive new theropod dinosaur track from the Cretaceous of Thailand: Implications for theropod track diversity. Cretaceous Research 27(1):139-145. doi: 10.1016/j.cretres.2005.10.002.

ABSTRACT: Highly distinctive, well-preserved, three-toed dinosaur footprints with bilobed heel impressions from the Cretaceous of Thailand are assigned to the new ichnotaxon Siamopodus khaoyaiensis. The tracks, which represent small- to medium-sized gracile theropods, are unlike any previously known from Thailand or elsewhere. By contrast other robust, small- to medium-sized theropod tracks with bulbous heel impressions are reported from a new locality and shown to be similar to Lower Cretaceous tracks from elsewhere in Asia. When added to previously reported robust, large theropod tracks, the Cretaceous track record in Thailand appears dominated by a significant diversity of theropod track types that differ from one locality to the next. Thus, the track record is in general agreement with the skeletal record of theropods in Thailand. The occurrence of footprints with bilobed heel impressions is reviewed briefly.


Then some from _P^3_, including one on dinosaurs:

Grellet-Tinner, G., Chiappe, L.M., Norell, M., and Bottjer, D. 2006. Dinosaur eggs and nesting behaviors: a paleobiological investigation. Palaeogeography, Palaeoclimatology, Palaeoecology 232(2-4):294-321. doi: 10.1016/j.palaeo.2005.010.029.

ABSTRACT: Although dinosaur eggs were first discovered and identified in the late 1800s, limited attention was given to the scientific value of oological fossils in contrast to observations based on skeletal features. Here, we offer a review of Mesozoic saurischian egg materials, in comparison with extant crocodilians and avians, and their paleobiological interpretation based either on the presence of embryos in ovo or brooding adults on egg clutches. Our study focuses on the eggs of the oviraptorid Citipati osmolka (Mongolia), the troodontid Troodon formosus (North America), the theropod oospecies Macroelongatoolithus xixiaensis (China), the ornithothoracine bird (Argentina), an indeterminate theropod (Thailand), and titanosaurs (Argentina). Results show that (1) many oological characters and reproductive behaviors associated with modern birds are rooted among non-avian theropods, (2) there is a reproductive evolutionary cline from crocodilians to modern birds with (3) a noticeable pattern of coeval development between the accretion of eggshell layers, origination and size increased of larger air cells (inferred from egg polar asymmetry), and brooding/incubating behaviors. Most of these pre-adaptations are grouped in two main clades of the saurischian cladogram: one at the level of Oviraptorosauridae and the other at Troodontidae. Although undeniably these two theropod taxa seem to represent two important phases for the evolution of avian reproduction, the phylogenetic distance between these clades and Titanosauria cannot be ignored. As such, the reproductive features that appeared in concert in oviraptorids might have gradually evolved across more basal theropod clades. Although Troodon formosus by its egg shape and nesting behavior seems to be in this study the precursors of modern avian reproduction, the importance of small-bodied theropods such as those who laid the Phu Phok eggs cannot be dismissed and the eggs of such dinosaurs could suggest a closer phylogenetic ties to Aves than troodontids. At a higher level of inferences, there is a strong possibility that the evolution of these reproductive features is concurrent with profound physiological and metabolic changes that occurred in saurischian dinosaurs throughout their evolution.

Friis, E.M., Pedersen, K.R., and Crane, P.R. 2006. Cretaceous angiosperm flowers: innovation and evolution in plant reproduction. Palaeogeography, Palaeoclimatology, Palaeoecology 232(2-4):251-293. doi: 10.1016/j.palaeo.2005.07.006.

ABSTRACT: Information on the fossil record of angiosperms has expanded dramatically over the past twenty-five years, and in particular the discovery of numerous mesofossil floras with fossil flowers has added a completely new element into the study of angiosperm history. A review of the phylogenetic diversification of angiosperms through the Cretaceous is given based mainly on the extensive record of fossil flowers and other reproductive organs. Several major phases in the Cretaceous angiosperm radiation can be distinguished. These are recognised primarily by structural and functional traits of the flowers and by pollen features, as well as distinct changes in the systematic composition of the floras. ANITA grade angiosperms and Chloranthaceae, as well as other magnoliids, early monocots and early eudicots, differentiated almost simultaneously during the Early Cretaceous. There is also strong evidence for extensive diversification of core eudicots during the Late Cretaceous. In addition to patterns of phylogenetic diversification, the fossil record of angiosperm flowers also provides insights into the timing of floral evolution in terms of the functions of the various kinds of floral organs, as well as accompanying patterns of ecological diversification.

Clack, J.A. 2006. The emergence of early tetrapods. Palaeogeography, Palaeoclimatology, Palaeoecology 232(2-4):167-189. doi: 10.1016/j.palaeo.2005.07.019.

ABSTRACT: Study of Devonian tetrapods and their relatives spanning the so-called 'fish-tetrapod' transition has expanded almost exponentially in the last 15 years or so. This evolutionary event is now represented by at least nine named genera of Devonian tetrapod, several new 'near-tetrapods' and a number of new tetrapods from the Early Carboniferous. The anatomy of Acanthostega has radically changed ideas about how this transition took place, and more recently the anatomy of Ichthyostega is being reassessed with some startling conclusions such as the unique construction of its ear region. The current state of research on this range of animals is summarized, followed by a consideration of the acquisition of limbs and digits among tetrapods including their possible forerunners, the development of digits and their original function, and the onset of pentadactyly. The faunal relations and palaeoecological contexts of the Devonian tetrapods are brought together in an initial though necessarily brief survey, followed by an assessment of Devonian tetrapod diversity, which is seen to be much greater than previously realised. Finally, some hopes and ambitions for the future are set out.


....and, lastly, some that aren't about dinosaurs but are kind of interesting anyway, from _Annales de Paleontologie_:

Antunes, M.T., Balbino, A.C., and Ginsburg, L. 2006. Miocene Mammalian footprints in coprolites from Lisbon, Portugal. Annales de Paléontologie 92(1):13-30. doi: 10.1016/j.annpal.2005.09.002.

ABSTRACT: For the first time, at least for the Lisbon Miocene series, uncommon ichnologic evidence has been recognized, i.e. mammalian footprints in coprolites. Three coprolites were recorded in three successive stratigraphic units, IVb and Va2 from the Lower Miocene to Vb from the early Middle Miocene. The largest, tridactyl footprint can be ascribed to a right foot of a rhinoceros. Size excludes all the rhinocerotids known from the Vb unit except Hispanotherium matritensis. A smaller coprolite (Va2 unit) shows a tridactyl, left foot impression of a perissodactyl. It is clearly too small for a rhinoceros, even for a young one. It seems to have been made by an Anchitherium Equid. The pes had a plantar pad as still found in the Mesohippus-Anchitherium lineage but not in more advanced Equids. Both tridactyl imprints may have been produced by the coprolite-makers. A large coprolite (IVb unit) that may have been produced by Brachyodus onoideus shows a few didactyl imprints. An artiodactyl trampled the dung with hoofs sliding on its surface and producing two incomplete imprints. It also trampled the dung in a more stable position, producing the best imprint, whose structure indicates it was produced by the left manus. The lack of lateral toe marks excludes suids (and Brachyodus, also because its size is too much small). It is from a small-sized ruminant, most probably a cervid, genus Procervulus. In all cases, defecation occurred on dry land, albeit in eventually or seasonally flooded areas near a river.

[Interestingly, I've been contending for years that one of the most definitive signs of a lack of intelligence on the part of nigh-extinct horses is that they willingly step in poop; guess this has been going on for millions of years...]

Antunes, M.T., Balbino, A.C., and Ginsburg, L. 2006. Ichnological evidence of a Miocene rhinoceros bitten by a bear-dog (Amphicyon giganteus). Annales de Paléontologie 92(1):31-39. doi: 10.1016/j.annpal.2005.10.002.

ABSTRACT: A rhinocerotid hemimandible, the Iberotherium rexmanueli zbyszewskii holotype, was bitten by Amphicyon giganteus, a carnivore that could attack large prey and be an opportunistic scavenger as well. The large, young adult Iberotherium was not senile and may have been killed by a single individual or by a pack of Amphicyon giganteus, but disease or accident may also have caused its death. Alternatively, during a drought event, a dying or in harsh physical condition rhinoceros may have been overcome while seeking a water point where ambush would be possible. Death also may have been a consequence of a major flood. As decay progressed and the remnants were eventually deposited, parts could have been consumed by scavengers. After consumption, wet bone surfaces could undergo some corrosion. Fissures may have resulted from desiccation or mechanical stress. The hemimandible was abandoned after consumption and left exposed until new sands were deposited over it.


Jerry D. Harris
Director of Paleontology
Dixie State College
Science Building
225 South 700 East
St. George, UT  84770   USA
Phone: (435) 652-7758
Fax: (435) 656-4022
E-mail: jharris@dixie.edu
and     dinogami@gmail.com

"Actually, it's a bacteria-run planet, but
mammals are better at public relations."
-- Dave Unwin