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The Nasep and Huns members of the Urusis Formation (Nama Group), southern Namibia, preserve some of the most diverse trace-fossil assemblages known from the latest Ediacaran worldwide, including potentially the world's oldest “complex” vertical sediment-penetrating burrows. These sediments record relatively diverse communities of bilaterian metazoans existing before the base of the Cambrian and an increase in the intensity of metazoan ecosystem engineering behaviors that could eventually produce profound changes in the character of the Phanerozoic sedimentary record (the “agronomic revolution”). Despite this, relatively little about this trace-fossil assemblage is known. We explore the Nasep–Huns transition at two localities in the Witputs sub-basin and describe the trace- and body-fossil diversity present in these horizons alongside a paleoenvironmental reconstruction. We document eight unique ichnotaxa from these localities, including well-preserved “probes” potentially left by priapulids. We also report the first occurrence of Corumbella from Namibia, helping to establish a biostratigraphic link between Namibia, Brazil, Paraguay, Iran, and the southwestern United States. Last, we find that several ichnotaxa, in particular small treptichnids, appear to be preferentially preserved on the bases of gutter casts, hinting at the potential existence of an unusual late Ediacaran preservational window with possible implications for timing the first appearance of key bilaterian behaviors.

The Jehol Biota is an Early Cretaceous terrestrial fossil assemblage of paramount significance, and its core distribution areas are western Liaoning, northern Hebei, and southeastern Inner Mongolia. Despite with a research history of more than 150 years, it started yielding important fossils until early 1990s, which include feathered dinosaurs, early birds, early mammals, flower-visiting insects, and early angiosperms. These discoveries have implications for understanding the origins and early evolution of several major organismal groups, as well as the origin and initial formation of modern terrestrial ecosystem. This review presents a brief introduction of the major discoveries, research history, and current understanding of this biota, and also provides future prospects for studying the Jehol Biota.

Planktonic foraminifera are instrumental in reconstructing paleoceanographic and paleoclimatic conditions. However, preferential dissolution can significantly bias both assemblages and chemical analyses, leading to biased interpretations. Bioerosional drill holes are commonly found in foraminiferal tests; however, it remains unknown if these marks increase the tests' vulnerability to dissolution. This study investigates how the number and size of drill holes affect the preservation of Globigerinoides ruber (comprising G. ruber albus and Globigerinoides elongatus) through an experimental approach. Sixty tests, extracted from a sediment core sample with variable bioerosion levels, were categorized into four groups based on the number of drill holes (0‐Control, I, III, IV). The tests were exposed to a buffered acetic acid solution and preservation was continually assessed through visual scoring and digital measurement of the test's area. These controlled conditions allowed the quantification of dissolution effects over time. Our results suggest that bioeroded tests are significantly more susceptible to dissolution when compared to non‐bioeroded ones. Tests with multiple drill holes (3 or 4) were especially vulnerable, showing rapid disintegration. Generalized linear models demonstrated that both the number and size of drill holes are key factors influencing the preservation indices. These findings emphasize the importance of accounting for bioerosion in paleoceanographic studies, as it compromises the tests preservation and potentially biases fossil assemblage interpretations. This study links bioerosion‐driven dissolution to global biogeochemical cycles and highlights the necessity to better document this process and account for it in Earth System Models.

Plant fossils play an important role in understanding landscape evolution across the Tibetan Region, as well as plant diversity across wider eastern Asia. Within the last decade or so, paleobotanical investigations within the Tibet Region have led to a paradigm shift in our understanding of how the present plateau formed and how this affected the regional climate and biota. This is because: (1) Numerous new taxa have been reported. Of all the Cenozoic records of new plant fossil species reported from the Tibet (Xizang) Autonomous Region 45 out of 63 (70%) were documented after 2010. Among these, many represent the earliest records from Asia, or in some cases worldwide, at the genus or family level. (2) These fossils show that during the Paleogene, the region now occupied by the Tibetan Plateau was a globally significant floristic exchange hub. Based on paleobiogeographic studies, grounded by fossil evidence, there are four models of regional floristic migration and exchange, i.e., into Tibet, out of Tibet, out of India and into/out of Africa. (3) Plant fossils evidence the asynchronous formation histories for different parts of the Tibetan Plateau. During most of the Paleogene, there was a wide east-west trending valley with a subtropical climate in central Tibet bounded by high (>4 km) mountain systems, but that by the early Oligocene the modern high plateau had begun to form by the rise of the valley floor. Paleoelevation reconstructions using radiometrically-dated plant fossil assemblages in southeastern Tibet show that by the earliest Oligocene southeastern Tibet (including the Hengduan Mountains) had reached its present elevation. (4) The coevolution between vegetation, landform and paleoenvironment is evidenced by fossil records from what is now the central Tibetan Plateau. From the Paleocene to Pliocene, plant diversity transformed from that of tropical, to subtropical forests, through warm to cool temperate woodland and eventually to deciduous shrubland in response to landscape evolution from a seasonally humid lowland valley, to a high and dry plateau. (5) Advanced multidisciplinary technologies and novel ideas applied to paleobotanical material and paleoenvironmental reconstructions, e.g., fluorescence microscopy and paleoclimatic models, have been essential for interpreting Cenozoic floras on the Tibetan Region. However, despite significant progress investigating Cenozoic floras of the Tibetan Region, fossil records across this large region remain sparse, and for a better understanding of regional ecosystem dynamics and management more paleobotanical discoveries and multidisciplinary studies are required.

The fossil record of past climate transitions offers insights into future biotic responses to climate change. Here, we compare shell growth dynamics, specifically linear extension and net calcification rates, of the bivalve Chamelea gallina between Northern Adriatic Sea assemblages from the Holocene Climate Optimum (HCO, 9 - 5 cal. kyr B.P.) and today. This species is a valuable economic resource, currently threatened by climate change and numerous anthropogenic stressors. During the HCO, regional sea surface temperatures were warmer than today, making it a potential analog for exploring ecological responses to increasing seawater temperatures predicted in the coming decades. By combining standard aging methods with reconstructed sea surface temperatures, we observed a significant reduction in linear extension and net calcification rates in warmer HCO assemblages. During the HCO, immature C. gallina specimens developed a denser shell at the expense of a linear extension rate, which was significantly lower than modern specimens. This resulted in an average delay of 3 months in reaching sexual maturity, which is currently reached after 13-14 months or at a length of ~ 18 mm. This study sheds light on the natural range of variability of C. gallina over longer time scales and its potential responses to near-future global warming.

Trace fossils are described for the first time from the Purpurberg Quartzite of the Weesenstein Group, where deposition is so far considered to be glacio-eustatic controlled during the ∼565 Ma-old Weesenstein–Orellana glaciation. The mineralogically mature quartzites are locally rich in trace fossils, but the bedding plane bioturbation index is commonly less than 3. The trace fossil assemblage is of low diversity and comprises abundant Palaeophycus isp. and Palaeophycus tubularis and rare Phycodes, likely Phycodes cf. palmatus. One large Lockeia siliquaria and likely also a poorly preserved Rusophycus? isp. were found. Based on these findings and regional correlation with quartz-rich sequences of Saxo-Thuringia, an Early Ordovician age is suggested for the Purpurberg Quartzite, which can be regarded as a facies equivalent to shallow marine, quartz-rich sequences of southwestern Europe deposited along the northern Gondwanan margin during the Early Ordovician. In the light of this new insight, stratigraphic implications for the Weesenstein diamictite are also briefly discussed.

This study integrates ichnological and sedimentological data to interpret depositional environments of the carbonate sediments of the Tirgan Formation (Lower Cretaceous) in the eastern Kopet-Dagh Basin, north-east Iran. Lithofacies analysis shows that these sediments were deposited in inner ramp, middle ramp and offshore (outer ramp) environments. Five ichnoassemblages are identified in the sediments that consist of Thalassinoides, Thalassinoides–Rhizocorallium, Planolites–Rhizocorallium, Arenicolites–Diplocraterion, and Arenicolites. Th, Th-Rh and Pl-Rh with low diversity and abundance of the trace fossils formed during waning phase of storms in a predominantly medium to high-energy hydrodynamic regime. High sedimentation rate and mobile substrate condition featuring a shallow-marine setting. Ar–Di ichnoassemblage, consisting of horizontal and vertical traces of deposit and suspension feeders, respectively, portray two different phases. A predominantly high energy phase with instable substrate is displayed by the vertical traces, while a minor omission phase, associated with a decrease in sedimentation rate or non-deposition, is indicated by the horizontal structures. Arenicolites ichnoassemblage with low bioturbation index and low ichnodiversity is related to a semi-sheltered area of lagoon environments with periodically marine water circulation. The study of the ichnological attributes in the studied successions indicates the presence of a shallowing up-ward trend in the storm‒tide-dominated ramp sequence. Ichnoassemblage development is largely controlled by depositional and ecological conditions, e.g., the stability of substrate, hydrodynamic regime (wave and tide), and food abundance, which altogether control the substrate colonization. Based on an integrated ichnological and sedimentological approach, we characterize the depositional environment, deciphering allogenic and autogenic environmental controls on the trace fossil distribution on a passive margin depositional setting.

The fossil record of past climate transitions offers insights into future biotic responses to climate change. Here, we compare shell growth dynamics, specifically linear extension and net calcification rates, of the bivalve Chamelea gallina between Northern Adriatic Sea assemblages from the Holocene Climate Optimum (HCO, 9 − 5 cal. kyr B.P.) and today. This species is a valuable economic resource, currently threatened by climate change and numerous anthropogenic stressors. During the HCO, regional sea surface temperatures were warmer than today, making it a potential analog for exploring ecological responses to increasing seawater temperatures predicted in the coming decades. By combining standard aging methods with reconstructed sea surface temperatures, we observed a significant reduction in linear extension and net calcification rates in warmer HCO assemblages. During the HCO, immature C. gallina specimens developed a denser shell at the expense of a linear extension rate, which was significantly lower than modern specimens. This resulted in an average delay of 3 months in reaching sexual maturity, which is currently reached after 13–14 months or at a length of ~ 18 mm. This study sheds light on the natural range of variability of C. gallina over longer time scales and its potential responses to near-future global warming.

The Ediacaran rangeomorph Fractofusus misrai is the most common and best-preserved of the E Surface fossil assemblage in the Mistaken Point Ecological Reserve of southeastern Newfoundland, Canada. Fractofusus has been interpreted as a fusiform epifaunal soft-sediment recliner, and like other rangeomorphs it has a self-similar, fractal-like branching morphology. The rangeomorph branching of Fractofusus has been considered to be identical on the upper and lower surfaces; however, study of specimens with complex biostratinomic histories suggests clear differences between the upper and lower surfaces. The first-order branches grew downwards into the sediment from a high point near the midline but grew above the sediment–water interface at their lateral and distal margins. Our new three-dimensional appreciation of rangeomorph branching in Fractofusus explains many of the taphomorphs of Fractofusus including straight, curved, kinked and tousled forms. The three-dimensional morphology, mode of life, taphonomy and palaeoenvironmental interactions of F. misrai are discussed along with a new three-dimensional reconstruction.

The Permian Period was a critical time interval during which various blocks of the Qinghai-Tibetan Plateau have experienced profound and complex paleogeographical changes. The supercontinent Pangea was formed to its maximum during this interval, hampering a global east-to-west trending equatorial warm ocean current. Meanwhile, a semi-closed Tethys Ocean warm pool formed an eastward-opening oceanic embayment of Pangea, and became an engine fostering the evolutions of organisms and environmental changes during the Paleozoic-Mesozoic transition. Stratigraphy and preserved fossil groups have proved extremely useful in understanding such changes and the evolutionary histories of the Qinghai-Tibetan Plateau. Widely distributed Permian deposits and fossils from various blocks of the Qinghai-Tibetan Plateau exhibited varied characteristics, reflecting these blocks’ different paleolatitude settings and drifting histories. The Himalaya Tethys Zone south to the Yarlung Zangbo suture zone, located in the northern Gondwanan margin, yields fossil assemblages characterized by cold-water organisms throughout the Permian, and was affliated to those of the Gondwanaland. Most of the exotic limestone blocks within the Yarlung Zangbo suture zone are Guadalupian (Middle Permian) to Early Triassic in age. These exotic limestone blocks bear fossil assemblages that have transitional affinities between the warm Tethys and cold Gondwanan regions, suggesting that they most probably represent seamount deposits in the Neo-Tethys Ocean. During the Asselian to Sakmarian (Cisuralian, also Early Permian), the Cimmerian microcontinents in the northern part of Gondwana preserved glacio-marine deposits of Asselian to Sakmarian, and contained typical Gondwana-type cold-water faunas. By the middle Cisuralian (∼290–280 Ma), the Cimmerian microcontinents rifted off from the Gondwanaland, and drifted northward allometrically due to the active magmatism of the Panjal Traps in the northern margin of the Indian Plate. Two slices of microcontinents are discerned as a result of such allometic drifting. The northern Cimmerian microcontinent slice, consisting of South Qiangtang, Baoshan, and Sibuma blocks, drifted relatively quickly, and preserved widespread carbonate deposits and warm-water faunas since Artinskian. By contrast, the southern Cimmerian microcontinent slice, consisting of Lhasa, Tengchong, and Irrawaddy blocks, drifted relatively slowly, and were characterized by widespread carbonate deposits containing warm-water faunas of late Kungurian to Lopingian (Late Permian). As such, these blocks rifted off from the northern Gondwanan margin since at least the Kungurian. Thus, it can be inferred that these blocks were incorperated into the low latitude, warm-water regions later than the northern Cimmerian slice. Such discrepancies in depositional sequences and paleobiogeography imply that the rifting of Cimmerian microcontinents resulted in the formation of both Meso-Tethys and Neo-Tethys oceans during the Cisuralian. By contrast, the North Qiangtang block, because of its further northern paleogeographical position, contains warm-water faunas throughout the whole Permian Period that are affiliated well with the faunas from the South China, Simao, and Indochina blocks. Together, these blocks belonged to the members of the northern Paleo-Tethys Ocean. Thus, an archipelagic paleogeographical framework divided by Paleo-, Meso-, and Neo-Tethys oceans was formed, fostering a global biodiversity centre within the Tethys warm pool. Since most of the allochthonous blocks assembling the Qinghai-Tibetan Plateau were situated in the middle to high latitude regions during the Permian, they preserved most sensitive paleoclimate records of the Late Paleozoic Ice Age (LPIA), the Artinskian global warming event, and the rapid warming event at the end-Permian. Therefore, sedimentological and paleontological records of these blocks are the unique window through which we can understand global evolutions of tectonic movement and paleoclimate, and their impacts on spatiotemporal distributions of comtemporaneous biotas.