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Understanding the processes that control speciation is critical to any modern macroevolutionary synthesis. A variety of theoretical constructs have been proposed to explain various differential speciation patterns observed in the fossil record, such as higher rates of speciation among stenotopic vs. eurytopic species. Most of these explanations, however, rely on only one or two explanatory variables and may be overly simplistic.

• Read more about Analysing links between biogeography, niche stability and speciation: the impact of complex feedbacks on macroevolutionary patterns

Although it has been variously defined and discussed, the ‘species problem’ in evolutionary palaeontology actually consists of at least three separate but closely related questions: (1) What are species in living organisms? (the ‘species nature problem’); (2) To what degree can ‘species’ as recognized in living organisms be recognized in the fossil record?

• Read more about Species, speciation and palaeontology up to the Modern Synthesis: persistent themes and unanswered questions

This contribution examines the Modern Synthesis in the light of its historical underpinnings, attempts at expansion and treatment of macroevolutionary theory. Particular emphasis is given to the need to better understand the patterns and processes operating on species and higher-level biological entities within a hierarchical framework, as they are often not congruent with lower-level processes. We then focus on the oft-overlooked importance of extrinsic abiotic drivers (e.g.

• Read more about A macroevolutionary expansion of the modern synthesis and the importance of extrinsic abiotic factors

The earliest record of a seed with a pappus-like, parachute seed dispersal mechanism, Edenia villisperma gen. et sp. nov., is described from the Upper Triassic of the eastern United States. The seed is small and roughly triangular. Clusters of long hairs emerge from a whorl of at least five circular scars just below the proximal end. This morphology indicates that the hair clusters represent modified lateral structures similar to the pappus of several eudicot angiosperm groups, but probably representing a case of convergent evolution of a similar structure in a gymnosperm.

• Read more about A Triassic seed with an angiosperm-like wind dispersal mechanism

• Read more about Corrigendum: Taxonomic status of the Least Grebe

Podicipediformes is a cosmopolitan clade of foot-propelled diving birds that, despite inhabiting marine and lacustrine environments, have a poor fossil record. In this contribution, we describe three new grebe fossils from the diatomite beds of the Late Miocene Truckee Formation (10.2 ± 0.2 Ma) of Nevada (USA). Two postcranial skeletons and an associated set of wing elements indicate that at least two distinct grebe species occupied the large, shallow Lake Truckee during the Miocene.

• Read more about Fossil grebes from the Truckee Formation (Miocene) of Nevada and a new phylogenetic analysis of Podicipediformes (Aves)

The upper Daguanshan Formation (middle Expansograptus hirundo graptolite biozone, Dapingian, early Middle Ordovician) of the Shuanghe area, Changning County, southern Sichuan Province, contains three new genera and species of strophomenoids: Ochyromena plana, Shuangheella elongata, and Primotimena globula, which are attributed to the Strophomenidae, Rafinesquinidae and Glyptomenidae respectively. These are the earliest known strophomenoids from the South China palaeoplate, and also the oldest rafinesquinid and glyptomenid brachiopods worldwide.

• Read more about The earliest known strophomenoids (Brachiopoda) from early Middle Ordovician rocks Of South China

Isolated and chemically bleached graptolite specimens of Baltograptus from Skattungbyn, Dalarna (central Sweden), reveal important new information on the internal construction of the tubarium. The specimens show the typical metasicular origin of th11 and the presence of numerous longitudinal rods in the prosicula. The investigation provides some insight into intraspecific variation and on the differentiation of individual species. It also provides information on the early evolution of the two-stiped dichograptids.

• Read more about The tubarium construction of Lower Ordovician (Dapingian) Baltograptus species (Graptolithina) from Dalarna, Sweden

The phylogenetic origin and the timing of origination of the Decabrachia are controversial. This is due to a poor understanding of character complexes relating to the shell, which causes difficulties in establishing homologies among different taxa. One central problem concerns a clear differentiation between belemnoids and early spirulids.

• Read more about Longibelus gen. nov., a new Cretaceous coleoid genus linking Belemnoidea and early Decabrachia

Systematic revision of the globally distributed deep-sea ostracod genera Pennyella Neale, 1974 and Rugocythereis Dingle, Lord and Boomer, 1990, which have been considered to correspond, at least partially, to nomen nudum but widely used genus name ‘Oxycythereis,’ was conducted to reduce taxonomic uncertainty of these important components of the Modern and fossil deep-sea ostracod community. Approximately 100 specimens from 18 species were examined, ranging in age from the Cretaceous to the present day.

• Read more about The 'Oxycythereis' problem: taxonomy and palaeobiogeography of deep-sea ostracod genera Pennyella and Rugocythereis