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The microsculpture and vascular markings of the classical species 'Spirifer' trigonalis are described, mainly from Scottish Brigantian (late Visean) specimens. The genus Angiospirifer and subfamily Angiospiri-ferinae are created. Angiospirifer is related to the genus Brachythyrina, which became widespread during the upper Carboniferous.

• Read more about A new genus of Carboniferous spiriferid brachiopod from Scotland

Several anatomically preserved stem fragments showing a wide range of surface features have been discovered among specimens of the Upper Pennsylvanian isoetalean Chaloneria cormosa. A comparison of the specimens demonstrates that stems produced a narrow zone of periderm, and that tissues external to the periderm accounted for a moderate increase in stem circumference by two distinctive modes of cell divisions.

• Read more about Cortical development in Chaloneria cormosa (Isoetales), and the biological derivation of compressed lycophyte decortication taxa

The occurrence of rich faunas of Lower Cretaceous inoceramid bivalves in the Antarctic Peninsula region further emphasizes their widespread distribution, and enhances their potential for regional biostrati-graphic correlations. The Antarctic material is contained in approximately seven of twelve species groups that are recognized on a worldwide scale. Six of these are assigned to the genus Inoceramus and one to Birostrina. The comparatively rare genus, Anopaea, is left undivided.In the Fossil Bluff Formation of Alexander Island, Berriasian representatives of the I. ovatus group (I. cf.

• Read more about Lower Cretaceous inoceramid bivalves from the Antarctic Peninsula region

Coronates are pelmatozoan echinoderms with a functional stem, a bud-shaped theca, and erect, biserial, pinnate arms. They evolved early in the Middle Ordovician, probably from the 'eocrinoid' Bockia, and gave rise to the blastoids sensu stricto. The subclass Coronata contains six genera. Mespilocystites (early Caradoc-Ashgill) had geniculate radial furrows, while all later genera had planar or gently convex radii. Of these Stephanoblastus (Caradoc-Wenlock) had a very narrow stem and triradiate keels at the base of the theca. All other genera had triangular thecal bases.

• Read more about Coronate echinoderms from the Lower Palaeozoic of Britain

Shales and siltstones of the Upper Proterozoic Veteranen Group, Spitsbergen, contain abundant and well-preserved microfossil populations. Plankton assemblages from open coastal deposits include a number of taxa previously known from Upper Riphean sequences in Scandinavia, the Soviet Union, and North America. Microfossils from more restricted coastal environments are dominated by small coccoidal unicells and filamentous sheaths of probable cyanobacteria, with locally abundant rod-shaped fossils of blue-greens or other bacteria.

• Read more about Micropalaeontology of the Late Proterozoic Veteranen Group, Spitsbergen

Active (flapping, powered) flight has evolved in only three groups of vertebrates: pterosaurs (late Triassic), birds (late Jurassic), and bats (early Tertiary). Gliding has arisen many times in vertebrates, is a separate adaptation from flying, and does not appear to be a prerequisite for active flight. Skeletal features that distinguish flyers from gliders include modifications of the pectoral and forelimb apparati, elongation of the distal part of the wing skeleton for thrust, and certain physiological modifications that often leave clues in the skeleton.

• Read more about The origins and aerodynamics of flight in extinct vertebrates [Palaeontology Review]

The enamel microstructure of single teeth and teeth in situ in whole jaws of late Jurassic, late Cretaceous, and Palaeocene multituberculates belonging to the Plagiaulacoidea, Taeniolabidoidea, Ptilo-dontoidea, and Meniscoessus (Cimolomyidae, suborder indet.) is examined by incident light microscopy, scanning electron microscopy (SEM), and polarized light microscopy. For comparison one docodont tooth and some single late Cretaceous and Recent eutherian teeth are included.

• Read more about The microstructure of tooth enamel in multituberculate mammals

A description is presented of the skull table of a protorothyridid captorhinomorph reptile from the lower Westphalian B ( Upper Carboniferous) of Newsham, Northumberland. The specimen, which is not named, represents the first reptile to he recorded from the Carboniferous of the British Isles and from the north-west European paralic Coal Measures.

• Read more about A protorothyridid captorhinomorph (Reptilia) from the Upper Carboniferous of Newsham, Northumberland

Recent collections from the Hanadir Shale (Llanvirn) include a more diverse trilobite fauna than was originally known. In addition to the previously described Plaesiacomia vacuvertis and Neseuretus (Neseuretus) tristani the following have been recognized: N. (N.) cf. tristani, P. sp. aff. P. ram, Kerfornella sp., Kloucekia sp., Ningkianolithus hanadirensis sp. nov., and asaphid indet. The fauna also includes graptolites, brachiopods, bivalves, ostracods, and orthocones. The trilobites confirm the 'Gondwanan' aspect of the fauna.

• Read more about Lower Ordovician trilobites from the Hanadir Shale of Saudi Arabia

The concept of global taxonomic diversity tending to an equilibrium state is central to many macroevolutionary hypotheses. It is widely accepted and considered to be corroborated by quantitative models of biotic diversification in the Phanerozoic. Those models assume diversity dependence of the rates of extinction and origination of taxa. This basic assumption, however, is contradicted by the empirical data. The process of diversification may depend on historical contingencies rather than on general macroevolutionary laws.

• Read more about Biotic diversification in the Phanerozoic: diversity independence