The Cambrian explosion ultimately resulted in the critical transition from microbially dominated ecosystems in the Precambrian to metazoan-dominated ecosystems in the Phanerozoic. However, the temporospatial pattern of ecosystems during the Cambrian explosion is poorly understood largely because our current knowledge is biased in metazoan evolution and redox conditions, and thus insufficient to reconstruct an ecosystem that is an integrative entirety of biotic and abiotic components. Therefore, we proposed a facies-dependent integrative approach as a working hypothesis toward a more comprehensive understanding of ecosystem evolution during the Cambrian explosion. The basis is to collect data from a rock unit with a consistent facies (or a biota) in five aspects: biodiversity, ecological network, climate, environmental trio (living, taphonomic and sedimentary conditions), and biogeochemical cycles. On the basis the temporospatial pattern can be built by tracking the spatial heterogeneity and tracing the temporal variability. Although the scenario is a general solution, not obligately applicable to the Cambrian explosion, and needs tremendous amount of work, it is a practical way, probably the only way, to understand such a global event with great complexity.

The Ordovician biodiversification is considered one of the most significant radiations in the marine ecosystems of the entire Phanerozoic. Originally recognized as the ‘Ordovician Radiation’, a label retained during most of the 1980s and 1990s, the term ‘Great Ordovician Biodiversification Event’ (GOBE) was coined in the late 1990s and was subsequently adopted by most of the scientific community. The Ordovician biodiversification, has always been considered as a long-term adaptive radiation, resulting in the sum of the different individual diversifications of all groups of marine organisms that occurred diachronously during the entire Ordovician. More recently, based on different palaeontological datasets, comprising data from different palaeogeographical areas, the Ordovician radiation has been interpreted to occur at different times in different places. This is most probably related to the palaeogeography of the Ordovician, when the major palaeocontinents were variously located in low latitudes to develop biodiversity ‘hotspots’ during different time intervals. In particular, some authors, using the potentially biased dataset of the Paleobiology Database (PBDB), have considered the GOBE to be an early Middle Ordovician global bio-event. Accordingly, the GOBE thus apparently corresponds to a relatively short time interval, with dramatic diversity fluctuations resulting in a profound change in marine environments at a global scale, visible by a major pulse in biodiversification of all fossil groups around the world. A critical analysis of the published biodiversity curves and of our own data confirm the traditional view; the Ordovician radiation is a complex, long-term process of multiple biodiversifications of marine organisms. Rapid increases in diversity can be identified for some fossil groups, at regional or palaeocontinental levels, in particular within limited datasets. However, a short, dramatic event that triggered major biodiversity pulses of all fossil groups at a global level at a particular time interval is an oversimplification.

A critical review of putative nonmarine mass extinctions associated with the so-called “Big 5 mass extinctions” of marine invertebrates (Late Ordovician, Late Devonian, end Permian, end Triassic and end Cretaceous) as well as a likely sixth mass extinction in the marine realm, the end-Guadalupian extinction, reveals little evidence of coeval marine and nonmarine mass extinctions. Little lived on land during the Ordovician other than a bryophyte-like flora that appears to have been diversifying, not going extinct, during the Late Ordovician. No case can be made for mass extinctions on land coeval with the marine extinctions of the Late Devonian-land plant diversity increased into the Carboniferous, and the tetrapod fossil record is inadequate to identify any mass extinctions. A case can be made for coeval plant/tetrapod extinctions and the end-Guadalupian marine extinctions, so this may be the first coeval marine-nonmarine mass extinction. However, problems of timing and questions about the extent of the nonmarine late/end-Guadalupian extinctions indicate that further research is needed. There were no mass extinctions of land plants, insects or tetrapods across the Permo–Triassic boundary. The Late Triassic was a time of low origination and high extinction rates on land and in the seas; there was no single end-Triassic mass extinction in either realm. The end-Cretaceous provides the strongest case for coeval land–sea mass extinctions, but there is no mass extinction of land plants, evidence of insect extinction is based on assumption-laden analyses of proxies for insect diversity and the tetrapod extinction was very selective. So, whether the nonmarine extinction at the end of the Cretaceous was a mass extinction is worth questioning. Part of the inability to identify nonmarine mass extinctions stems from taphonomic megabiases due to the relatively poor quality and uneven sampling of the nonmarine fossil record. Extinction resistance and resilience of terrestrial organisms is also a likely factor in the dearth of nonmarine mass extinctions, and this merits further investigation.

Analyses of planktic foraminiferal assemblage data, test morphology, and stable oxygen isotopes from the Integrated Ocean Drilling Program (IODP) Site U1304 in the North Atlantic reveal a stepwise regional migration of the oceanic fronts around 0.6 Ma and 0.4 Ma, i.e., during Marine Isotope Stages (MISs) 15 and 11, respectively. Both changes of planktic foraminiferal assemblages and shell carbonate isotopes indicate that the cold Arctic waters in general persisted at IODP Site U1304 from 1.6 to 0.6 Ma (MIS 15), even though the warmer waters originating from the Atlantic waters episodically bathed Site U1304 during the interglacial periods. During the time-interval from ca. 0.6 to 0.4 Ma (MISs 15–11), an alternating dominance of Artic and Atlantic waters at the Site U1304 has been suggested from isotopic evidence. In MIS 11, the dominant planktic foraminiferal species Neogloboquadrina pachyderma experienced a short-term but significant decrease in test size. The test-size change may have been caused by accelerated reproduction in more favorite feeding conditions over the long-lasting interglacial period around the Subarctic Front. This finding is supported by the presence of massive diatoms oozes in the same time-interval. The modern-type glacial/interglacial change of the surface water system established since ca. 0.4 Ma (MIS 11) followed the Mid-Brunhes Event.

Two coeval assemblages of fossil fishes came from the middle–late Miocene deposits of Sakhalin Island, Russia. The fish community from the Agnevo Formation consists of 28 species belonging to 15 families of shallow-water fishes, with the predominance of cottoids, stichaeoids, and pleuronectoids. The assemblage from the Kurasi Formation contains fossils of 35 species from 27 fish families and comprises mainly mesopelagic dwellers, such as myctophids, argentiniforms, stomiiforms, and aulopiforms. These assemblages differ mainly in the number of species belonging to extinct genera. Among the 28 fish genera known from the Agnevo Formation, 14 (50%) genera are extinct. In contrast, out of 35 genera described from the Kurasi Formation only three (about 8.6%) genera are extinct. The morphological distances between the fossil and recent congeneric species are more pronounced and defined in the shallow-water community than in the deep-water assemblage. The differences in taxonomic composition between the fossil assemblages likely reflect the different influence of the climatic and geographic events in the Neogene and Quarternary on the evolutionary rates of shallow- and deep-water fish communities.

The turbinid gastropod Turbo (Marmarostoma) is common in the limestone bodies within the middle Miocene Sakurada and Kadono formations (Yugashima Group) on the Izu Peninsula, central Japan. The limestone bodies were originally deposited under a low-latitude, tropical climate in the northeastern Philippine Sea and then drifted northwards on the Philippine Sea Plate. This paper describes an additional species, Turbo (Marmarostoma) ishidai sp. nov., from the Ena Limestone on the south-western Izu Peninsula. This new species is characterized by its large shell size and shell form similar to the modern Australian endemic species Turbo (Marmarostoma) cepoides , but differs in having thick tuberculate spiral cords on the shell surface of earlier teleoconch whorls instead of the smooth and broad spiral cords on and around the angled shoulder. The addition of this new species further highlights the presence of a biodiversity hotspot of this gastropod group in the northeastern Philippines Sea during the middle Miocene.

Crayfish are rare in the fossil record and therefore it is important to investigate each occurrence in detail. The only known fossil crayfish from France, Astacus edwardsi Van Straelen, 1928, is known from a replica made by pouring plaster of Paris inside the holotype (subsequently destroyed), an external mould extracted from a travertine cavity from the Thanetian of Sézanne. An evaluation of the taxonomic name, A. edwardsi, is provided; A. edwardsi is considered valid in accordance with ICZN rulings. It possesses atypical features for all other astacid genera, thus Emplastron gen. nov. is erected. Emplastron edwardsi gen. et comb. nov. inhabited a warm climate with calm waters, abundant food sources, and an ample supply of calcium carbonate: so much so that it is surprising that it is the only recovered specimen. Despite apparent North American faunal and floral affinities in the vicinity, E. edwardsi is more closely related to European crayfishes than it is to American ones.