Footprints pull origin and diversification of dinosaur stem lineage deep into Early Triassic

The ascent of dinosaurs in the Triassic is an exemplary evolutionary radiation, but the earliest phase of dinosaur history remains poorly understood. Body fossils of close dinosaur relatives are rare, but indicate that the dinosaur stem lineage (Dinosauromorpha) originated by the latest Anisian (ca 242-244 Ma). Here, we report footprints from the Early-Middle Triassic of Poland, stratigraphically well constrained and identified using a conservative synapomorphy-based approach, which shifts the origin of the dinosaur stem lineage back to the Early Olenekian (ca 249-251 Ma), approximately 5-9 Myr earlier than indicated by body fossils, earlier than demonstrated by previous footprint records, and just a few million years after the Permian/Triassic mass extinction (252.3 Ma). Dinosauromorph tracks are rare in all Polish assemblages, suggesting that these animals were minor faunal components. The oldest tracks are quadrupedal, a morphology uncommon among the earliest dinosauromorph body fossils, but bipedality and moderately large body size had arisen by the Early Anisian (ca 246 Ma). Integrating trace fossils and body fossils demonstrates that the rise of dinosaurs was a drawn-out affair, perhaps initiated during recovery from the Permo-Triassic extinction.     

Is It Human? Discriminating between Real Tracks and Track-Like Structures

Some human footprints-like hollows in the tuffaceous ground of an ancient quarry and of a recent anthropic path, created by the inhabitants no more than 30 years ago near the small village of Carangi (Caserta province, Southern Italy), allowed scientists to study some of the most misleading alteration processes of the volcanic tuff formations. The closeness of this site to the “Ciampate del Diavolo” ichnosite, bearing some of the oldest human fossil footprints, and the common stratigraphical and sedimentological background permitted accurate comparisons between actual human fossil footprints and footprint-like depressions, which can be easily mistaken for actual fossil evidence. This comparative study has permitted the reporting of some useful features and advice on distinguishing actual fossil footprints from natural and/or anthropic pseudo-tracks.     

HISTORY OF ICHNOLOGY—Ichnological Eccentrics: The Curious Case of Dr. Joseph Barratt of Middletown,Connecticut

Joseph Barratt was a British-born and educated physician who settled in the United States in 1819. He had a great interest in natural history, collecting both plants and insects and studying geology, mycology, ornithology, chemistry, meteorology, Native Americans, and local history. He was apparently a man of great energy and ambition but one who could not focus to see a project to completion. Barratt was active in the early history of the discovery of vertebrate footprints in the Newark Supergroup in the eastern United States but latter developed some very strange theories regarding the age and significance of these deposits. In his latter years, Barratt's mental state deteriorated and he became even more obsessed with trying to publicize his outlandish theories. Dr. Joseph Barratt is remembered in ichnology for basically two things; he sold Edward Hitchcock a superb specimen of vertebrate tracks; and he may have the most elaborate ichnological tombstone ever constructed.     

Mayfly Burrows in Firmground of Recent Rivers from the Czech Republic and Poland,with Some Comments on Ephemeropteran Burrows in General

U-shaped, pouch-like burrows with parallel limbs, covered with short scratches arranged in sets, occur in the thalweg of the Oh?e river in NW Czech Republic. Similar, but smaller burrows with rare scratches, not arranged in sets, occur in the thalweg of the Drw?ca river in N Poland. Probably, they are produced by larvae and/or nymphs of Palingenia and Polymitarcis (Ephoron), respectively. In both localities, they burrowed in firmground surfaces at shallow depths. The burrowed surfaces were emerged during low water levels. A review of recent mayfly burrows shows that they are 1) U-shaped pouches with parallel limbs and septum, which may be covered with short scratches and are oriented perpendicular to the bottom, irrespective of its inclination, or 2) wide U-shape burrows with divergent limbs, which may be branched. In the fossil record, the ichnogenera Fuersichnus, Asthenopodichnium, and Rhizocorallium are partly ascribed to mayfly burrows, but their comparison to the recent burrows shows that such interpretations are somewhat problematic. The mayfly burrows are potentially good indicators of aquatic, non-marine, well oxygenated, clean water environments.     

Chemical state of magnesium in plasma

All the magnesium in ovine and bovine plasma behaves as a low molecular weight cationic complex. No plasma magnesium is associated with protein.     

The Lower Triassic Werfen Formation of the Karawanken Mountains (Southern Austria) and its disaster survivor microfossils, with emphasis on Postcladella n. gen. (Foraminifera, Miliolata, Cornuspirida)

A relatively poorly known sedimentary succession (uppermost Bellerophon Formation and overlying Werfen Formation) including the Permian-Triassic Boundary (PTB) is exposed in the South-Alpine part of the Karawanken Mountains of Southern Austria. As in the Dolomites, sedimentation of the Werfen Formation mainly occurred in a subtidal shelf environment between normal and storm wave base. Muddy sedimentation was periodically interrupted by storm events resulting in the deposition of storm layers. Three sections are accurately studied. All contain the same assemblage of Foraminifera and events from the PTB to the late Early Triassic Meandrospira pusilla zone. Between these two great events, only the cornuspirid foraminiferan Postcladella n. gen. is present. Its populations are described and illustrated here under the name Postcladella kahlori n. comb. In the geological record, many taxa such as P. kahlori, i.e., undivided, tubular, initially planispirally evolute coiled, and later uncoiled, appeared successively. A reappraisal is attempted in order to discriminate the different taxa. These forms are often disaster survivors.     

Recent borings in limestone cobbles from Marloes Bay, southwest Wales

Limestone clasts from the beach at Marloes Sands, southwest Wales, contain slender, straight to sinuous borings cross-cut by younger, clavate borings. The former were probably produced by sipunculids or polychaetes; the latter preserve shells of the boring bivalve Gastrochaena dubia (Pennant). Unusually, the calcareous linings of the clavate bivalve borings extend into many of the slender worm borings. Such linings are considered part of the hard parts of the producing bivalve, but the chance association of the two morphologies of borings has led to the lining becoming intimately associated with both of them. The modified linings of the bivalve borings have a similar morphology to the crypt of certain clavagellid bivalves, perhaps presenting an analogue for the morphology of a pre-clavagellid, boring ancestor.     

The mechanism of cell-mediated cytotoxicity. IV. K-76 COONa, which inhibits the activity of Factor I and of C5, inhibits early events in cytotoxic T-lymphocyte-mediated cytolysis and in T-lymphocyte activation

K-76 COONa is a derivative of a fungal product which blocks complement (C)-mediated lysis by combining with C5 and preventing its activation to C5b. K-76 COONa can also combine with Factor I and inhibit its ability to hydrolyze C3b to iC3b. The inclusion of K-76 COONa at concentrations similar to those which inhibit C lysis blocked both murine cytotoxic-T-lymphocyte (CTL)-mediated lysis (CML) and the lectin-stimulated proliferative response of murine and human T lymphocytes. A modified cation pulse procedure has been used to determine which phases of CML were most sensitive to the drug. K-76 COONa was inhibitory when it was added to CML prior to the early Mg+2-dependent binding phase, but was much less effective when it was added at any time after the formation of CTL-target conjugates. The principal effect of the drug on the proliferative response was also exerted during an early phase of the response. K-76 COONa did not appreciably decrease the production of T-cell growth factor (TCGF), but it did inhibit the induction of TCGF receptor expression by both functional criteria, i.e., induction of responsiveness to TCGF, and by morphological criteria, i.e., the expression of the Tac antigen. Later events, such as the TCGF-dependent proliferation of cycling T cells, were less sensitive to the drug. Evidence is discussed suggesting that molecules similar to Factor I and to C3 may be involved both in the early events of CML and of T-lymphocyte activation.     

Response of <Emphasis Type="Italic">Arnica dealbata</Emphasis> to climate change,nitrogen deposition,and fire

Predicted changes in climate and increasing nitrogen deposition are likely to have significant impacts on species that have limited distributions or are already experiencing diminished population size. Arnica dealbata (A. Gray, Asteraceae), a listed sensitive species in Yosemite National Park, is endemic to California and has limited distribution within the park boundaries. The objective of this research was to examine the effects of altered precipitation resulting from climate change, increasing nitrogen deposition resulting from pollution, and prescribed fire on A. dealbata. A. dealbata cover significantly increased with increasing snowpack and prescribed fire. Increasing nitrogen deposition negatively affected cover. Our results suggest Yosemite’s A. dealbata populations can thrive even under a changing climate if prescribed fire is frequently applied coupled with increased moisture availability.