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The affinity of Tullimonstrum gregarium, a pincer‐mouthed, soft bodied bilaterian, has been subject to debate since its recovery from Carboniferous coal deposits at Mazon Creek, Illinois. After decades of impasse focused on mollusc, arthropod and annelid attributes, two recent, yet conflicting, high‐profile studies concluded that the ‘Tully Monster’ is a vertebrate, a relative of lampreys or jawed fishes.

• Read more about The ‘Tully Monster’ is not a vertebrate: characters, convergence and taphonomy in Palaeozoic problematic animals

Extant baleen whales (Cetacea, Mysticeti) are a disparate and species‐rich group, but little is known about their fossil record in the northernmost Atlantic Ocean, a region that supports considerable extant cetacean diversity. Iceland's geographical setting, dividing North Atlantic and Arctic waters, renders it ideally situated to shed light on cetacean evolution in this region. However, as a volcanic island, Iceland exhibits very little marine sedimentary exposure, and fossil whales from Iceland older than the late Pleistocene are virtually unknown.

• Read more about The oldest marine vertebrate fossil from the volcanic island of Iceland: a partial right whale skull from the high latitude Pliocene Tjörnes Formation

The tuatara, Sphenodon punctatus, known from 32 small islands around New Zealand, has often been noted as a classic ‘living fossil’ because of its apparently close resemblance to its Mesozoic forebears and because of a long, low‐diversity history. This designation has been disputed because of the wide diversity of Mesozoic forms and because of derived adaptations in living Sphenodon. We provide a testable definition for ‘living fossils’ based on a slow rate of lineage evolution and a morphology close to the centroid of clade morphospace.

• Read more about Macroevolutionary patterns in Rhynchocephalia: is the tuatara (Sphenodon punctatus) a living fossil?

For taphonomic and practical reasons, our understanding of morphological evolution within and among species is based primarily on measurements taken from one or a few morphological traits. However, patterns can be highly dependent on trait choice, making it difficult to draw conclusions about evolution of species or clades as a whole. In this paper, I test whether patterns of evolutionary change in the shape of a part are coincident with patterns of evolutionary change based on a more comprehensive description of the organism.

• Read more about How well does a part represent the whole? A comparison of cranidial shape evolution with exoskeletal character evolution in the trilobite family Pterocephaliidae

We describe the skull and neck morphology of the late Miocene amphicyonid Magericyon anceps, focusing on aspects related to functional anatomy. This species, recorded only from the Vallesian sites of Batallones‐1 and Batallones‐3 (Madrid, Spain), is the last known amphicyonid in the fossil record of Western Europe, with the Batallones populations being one of the best‐known of the family. The morphology of its skull and cervical vertebrae allows us to infer aspects of its associated musculature, such as muscle strength and range of movement.

• Read more about Functional anatomy of the cervical region in the late Miocene amphicyonid Magericyon anceps (Carnivora, Amphicyonidae): implications for its feeding behaviour

The enigmatic fissure deposits of south‐western England and southern Wales are famous for their unique assemblage of Late Triassic vertebrates, although their age is contentious. While recent studies of palynomorphs have dated some as Rhaetian, their conchostracan (Crustacea, Branchiopoda) assemblages have not been described in detail nor used in biostratigraphy. We find that species determination of British Late Triassic conchostracans requires detailed observations of size, shape and ornamentation.

• Read more about Biostratigraphy and geometric morphometrics of conchostracans (Crustacea, Branchiopoda) from the Late Triassic fissure deposits of Cromhall Quarry, UK

Dietary specialization is generally considered to be a crucial factor in driving morphological evolution across extant and extinct vertebrates. The ability to adapt to a specific diet and to exploit ecological niches is thereby influenced by functional morphology and biomechanical properties. Differences in functional behaviour and efficiency can therefore allow dietary diversification and the coexistence of similarly adapted taxa.

• Read more about Functional niche partitioning in Therizinosauria provides new insights into the evolution of theropod herbivory

The stegosaurs are some of the most easily recognizable dinosaurs, but are surprisingly rare as fossils. Consequently much remains unknown about their palaeobiology, and every new stegosaurian find contributes to our understanding of the evolution of the clade. Since the last attempt to examine the evolutionary relationships of Stegosauria, new specimens have come to light, including the most complete individual of Stegosaurus ever found, new taxa have been described and, perhaps most importantly, new methods for analysis of cladistic datasets have been produced.

• Read more about A new phylogeny of Stegosauria (Dinosauria, Ornithischia)

A lower jaw of the mesonychian Hapalodectes is reported from Nongshanian sediments (Upper Doumu Formation; middle Paleocene) of the Qianshan Basin (Anhui Province, China). The fragmentary mandible is only the third specimen of Hapalodectidae discovered in Paleocene deposits, and the first in south east China; it is moreover the oldest, the two other specimens having been found in Gashatan (late Paleocene) localities.

• Read more about The first species of Hapalodectes (Mesonychia, Mammalia) from the middle Paleocene of China (Qianshan Basin, Anhui Province) sheds light on the initial radiation of hapalodectids

Laboratory experiments documenting the decomposition pattern of extant organisms are used to reconstruct the anatomy and taphonomy of fossil taxa. The subclass Graptolithina (Hemichordata: Pterobranchia) is a significant fossil taxon of the Palaeozoic era, represented by just one modern genus, Rhabdopleura. The rich graptolite fossil record is characterized by an almost total absence of fossil zooids. Here we investigated the temporal decay pattern of Rhabdopleura sp. tubes, stolons and single zooids removed from the tubarium.

• Read more about Fossilization processes of graptolites: insights from the experimental decay of Rhabdopleura sp. (Pterobranchia)