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New findings from articulated head and trunk material of Megamastax amblyodus yield previously unseen morphological details of a Silurian stem osteichthyan.

A large, lobe-finned fish from the Late Devonian of China disrupts previously accepted stem-tetrapod phylogeny and reveals parallel evolution within the lineage.

Two new species of well-preserved jawed fishes with complete bodies from the early Silurian period (Telychian age, around 436 million years ago) of Chongqing, South China are described: a jawed stem gnathostome, Xiushanosteus mirabilis, and a chondrichthyan, Shenacanthus vermiformis.

The earliest body fossils of tetrapods (vertebrates with limbs rather than paired fins) date to the Late Devonian period. There have been claims of tetrapod trackways predating these body fossils but the age and identity of the track makers have remained controversial. The discovery of well-preserved and securely dated tetrapod tracks from Polish marine tidal flat sediments of early Middle Devonian age, around 18 million years older than the earliest tetrapod body fossils, is now presented.

A tiny, articulated, near-complete osteichthyan from the early Silurian Chongqing Lagerstätte, represents the oldest osteichthyan occurrence including microfossils, and the earliest articulated remains of any bony fish in the fossil record.

The extinct Andreolepis, an early fish that is close to the common ancestor of all bony fish and land vertebrates, shed its teeth by basal resportion—the earliest example of this mode of tooth replacement.

Enamel is a tissue unique to vertebrates, and nowadays associated with teeth; here, histological material from a fossil bony fish and genomic data from an extant, armour-plated fish are analysed to show that enamel originated on the body surface and only later colonized the teeth.

The transition from water to land during the late Devonian is marked by the early tetrapods Ichthyostega and Acanthostega, and the tetrapod-like fish Tiktaalik. An analysis of recently discovered material shows that Ventastega curonica might be seen as a simple intermediate between the Tiktaalik and Acanthostega. However, the picture is more complicated than this due to the unexpected morphological diversity of early tetrapods.

Analysis of a fossil trackway from the earliest Carboniferous of Australia shows prints of toes with claws, suggesting that the origin of amniotes was at least 35–40 million years earlier than previously thought.

Synchrotron imaging of fossil and extant coelacanths reveals that the lung of extinct species likely served both respiratory and auditory functions, transmitting sound pressure to the inner ear via a specialized perilymphatic system

Fossilized gut contents of an Ordovician trilobite shed light on the feeding habits of one of the most common and well-known extinct arthropods.

Three-dimensionally preserved fossils of Parmastega aelidae, a newly described tetrapod from the earliest Famennian (Late Devonian) of Russia, provide detailed insights into the morphology and palaeobiology of the earliest tetrapods.

Integrated analyses of bromalites provide robust pictures of past food webs, explaining early dinosaur evolution and the emergence of larger dinosaur faunas with new feeding patterns.

The presence of blubber and distribution of melanophores in a countershading pattern in an Early Jurassic ichthyosaur demonstrate that the evolutionary convergence of these reptiles with extant marine amniotes extends to the cellular and molecular levels.

Studies of the head of the very primitive jawed vertebrate Romundina show that it combines jawed vertebrate architecture with cranial and cerebral proportions resembling those of extant jawless vertebrates such as lampreys.

The discovery of claspers in fossils of antiarch placoderms, an ancient group of armoured fish, suggests that internal fertilization was the ancestral type of reproduction for all jawed vertebrates: this contrasts with the current understanding that external fertilization must be the ancestral state.

The discovery of embryos in certain fossil fishes not only shows that internal fertilization and live birth evolved early in vertebrate history, but also raises questions about the origin of jawed vertebrates.

X-ray synchrotron microtomography has revealed the three-dimensional vertebral architecture of Ichthyostega, and other crucial and celebrated early tetrapods; a surprising feature is the relationship between the vertebral elements, with the pleurocentra unexpectedly attached to the succeeding intercentrum, suggesting a ‘reverse’ rhachitomous design.

Analysis of fossil limb bones suggests that a mass-death deposit of the Devonian tetrapod Acanthostega may consist entirely of juveniles, throwing new light on the life history of this species and the evolution of terrestriality.

Detailed micro-computed tomography analysis of the skull of Lethiscus stocki places it much earlier in the tetrapod lineage that was previously thought, showing that early tetrapods were more morphologically diverse than has been believed.

The first unambiguous evidence for osteichthyan (bony fishes, including tetrapods) characters in two previously known Late Silurian (423–416 Myr) fishes is reported, demonstrating that they are not only the oldest, but phylogenetically the most primitive osteichthyans known to date

Early hypotheses suggested that the digits of tetrapods (land vertebrates) were homologues of fin radials, but this idea fell out of favour on the basis of developmental studies and also on the fin of Panderichthys, a fish closely related to land vertebrates, which appeared to lack distal digit-like fin radials. A new CT study of a classic specimen of Panderichthys shows that the old interpretation was in error. Panderichthys did indeed have digit-like radials: nothing stands in the way of the era of fish fingers.

Although the origin of jaws is one of the key episodes in the evolution of vertebrates, the jaw bones of modern bony fishes and limbed vertebrates differ so much from those in any other groups that the individual evolutionary steps in the transition are still unknown; here Entelognathus is described, an early placoderm fish with full body armour, but with marginal jaw bones similar to those of modern bony fishes and limbed vertebrates.

Comparing the eyes of crane-fly fossils with those of extant species demonstrates that they contain eumelanic screening pigments and that the lenses are calcified during fossilization, with implications for interpreting optical systems in other extinct arthropods such as trilobites.