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The anatomy and affinities of Jamoytius kerwoodi White have long been controversial, because its complex taphonomy makes unequivocal interpretation impossible with the methodology used in previous studies. Topological analysis, model reconstruction and elemental analysis, followed by anatomical interpretation, allow features to be identified more rigorously and support the hypothesis that Jamoytius is a jawless vertebrate.

• Read more about Taphonomy and affinity of an enigmatic Silurian vertebrate, Jamoytius kerwoodi White

A systematic revision of the sabre-toothed cat genus Paramachaerodus Pilgrim, 1913 is presented. Two species are recognized within Paramachaerodus, Pa. orientalis, and Pa. maximiliani, and the genus Promegantereon Kretzoi, 1938 is retrieved to include Promegantereon ogygia. Material from the Turolian Spanish localities of Crevillente-2 (MN 11, Alicante) and Las Casiones (MN 13, Teruel), which was previously assigned to Paramachaerodus, is now included in the tribe Metailurini.

• Read more about Systematic revision of the Late Miocene sabre-toothed felid Paramachaerodus in Spain

The middle Cambrian strata of the Iberian Chains (north-eastern Spain) and the Montagne Noire (southern France) record an adaptative radiation of cinctans and trilobites, which spanned the Leonian–early Languedocian interval. A diachronous diversity peak was reached by both benthic groups when favourable palaeoenvironmental conditions (clayey vs. silty substrates) were established. The acme in diversity was followed by a gradual decline and a barren interval associated with the onset of the mid-Languedocian regression, well constrained throughout the western Mediterranean region.

• Read more about Testing for a decline in diversity prior to extinction: Languedocian (latest mid-Cambrian) distribution of cinctans (Echinodermata) in the Iberian Chains, NE Spain

A rich coral-associated decapod assemblage is recorded from the ‘Depiru Beds’ of the upper part of the Upper Coralline Limestone (Messinian, Upper Miocene), from the island of Malta. Nineteen species within 17 genera have been discovered, where 14 genera are new for Malta. Four new species are described, namely Micippa annamariae sp. nov., Pilumnus scaber sp. nov., Panopeus muelleri sp. nov. and Herbstia melitense sp. nov. Herbstia melitense sp. nov. constitutes the first record of the genus from the fossil record in the Mediterranean region.

• Read more about A new coral-associated decapod assemblage from the Upper Miocene (Messinian) Upper Coralline Limestone of Malta (Central Mediterranean)

Markuelia is a vermiform, annulated introvertan animal known as embryonic fossils from the Lower Cambrian to Lower Ordovician. Analysis of an expanded and revised dataset for Introverta shows that the precise position of Markuelia within this clade is dependent on the taxa included. As a result, Markuelia is assigned to the scalidophoran total group to reflect uncertainty as to whether it is a stem-scalidophoran or a stem-priapulid. The taxonomy of the genus is revised to provide an improved taxonomic framework for material assigned to Markuelia. Five species are recognized: M.

• Read more about The anatomy, taphonomy, taxonomy and systematic affinity of Markuelia: Early Cambrian to Early Ordovician scalidophorans

The palaeohistological study of the calcified internal organ of Axelrodichthys araripensis Maisey, 1986, a coelacanthiform from the Lower Cretaceous of Brazil (Crato (Aptian) and Santana (Albian) formations of the Araripe Basin), shows that the walls of this organ consist of osseous blades of variable thickness separated from each other by the matrix. This indicates that, in the living individuals, the walls were reinforced by ossified plates, probably separated by conjunctive tissue.

• Read more about The histological structure of the calcified lung of the fossil coelacanth Axelrodichthys araripensis (Actinistia: Mawsoniidae)

We studied morphological variation of the bivalve Buchia over its geographical and temporal range. Buchia was widely distributed during the Late Jurassic and Early Cretaceous, and, while previous quantitative studies have shown that species are characterized by large amounts of variation, there have been no prior attempts to measure how morphology varies geographically. We employed traditional morphometric techniques using nine linear/angular measurements on 1855 buchiid shells from eight localities taken from widely separated, but mostly coeval, sections across its range.

• Read more about Morphological variability in time and space: an example of patterns within buchiid bivalves (Bivalvia, Buchiidae)

Body size is a common focus of macroevolutionary, macroecological and palaeontological investigations. Here, we document body-size evolution in 19 species-level ostracod lineages from the deep Indian Ocean (Deep Sea Drilling Program Site 253) over the past 40 myr. Body-size trajectories vary across taxa and time intervals, but most lineages (16/19) show net gains in body size.

• Read more about Climate-driven body-size trends in the ostracod fauna of the deep Indian Ocean

Using Whittaker’s concepts of alpha, beta, and gamma diversity, Sepkoski asked how global diversity was assembled at scales ranging from the community to the province. In the years since, ecologists have recast diversity in terms of additive partitions where total diversity can be decomposed into sample-level alpha diversity plus the sum of a series of beta diversity terms that reflect progressively larger spatial scales.

• Read more about Additive diversity partitioning in palaeobiology: revisiting Sepkoski's question

The Paleobiology Database now includes enough data on fossil collections to produce useful time series of geographical and environmental variables in addition to a robust global Phanerozoic marine diversity curve. The curve is produced by a new ‘shareholder quorum’ method of sampling standardization that removes biases but avoids overcompensating for them by imposing entirely uniform data quotas. It involves drawing fossil collections until the taxa that have been sampled at least once (the ‘shareholders’) have a summed total of frequencies (i.e. coverage) that meets a target (the ‘quorum’).

• Read more about Geographical, environmental and intrinsic biotic controls on Phanerozoic marine diversification