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From the late Carboniferous to the early Permian, multiple pulses of glaciation and deglaciation have been caused by the LPIA. The Pennsylvanian period experienced phases of recovery, proliferation, and decline, ultimately forming a reef system distinctly different from that of the Mississippian period. During the late Bashkirian to Moscovian, the metazoan reef experienced a limited resurgence, with reef predominantly formed by chaetetid developing in the United States, northern China, and Japan. During the Kasimovian to Gzhelian, the phylloid algal reef dominated the global reef systems. In the late Pennsylvanian, bioconstruction cases and paleoenvironmental proxies in southern Guizhou Province were studied to investigate the composition, recovery, and evolutionary processes of the bioconstructions as well as their response to environmental variations during this period. Several bioconstructions have been reported in the Lumazhai section of Houchang Town, Guizhou Province, southern China, from the Moscovian to the Gzhelian. The upper Carboniferous strata are well-preserved and continuously exposed. The continuous strata, abundant fossils, and diverse bioconstructions provide excellent research materials for exploring the mutual constraints between organisms and their environment. This study identified ten microfacies, whose vertical evolution indicated significant changes in the depositional environment related to relative sea-level fluctuations. Skeletal grains are widely present in these facies. Among them, foraminifera, algae, bryozoans, crinoids, and Tubiphytes are the most common and exhibit distinct distribution characteristics in various environments. Quantitative statistics, CCA and theoretical ecospace have been utilized to examine and interpret environmental impact factors. Quantitative analysis of their relative abundance and distribution patterns provides insights into the complex interactions between organisms and environmental factors. The relative abundances of different organisms and factors controlling their bioconstructions are influenced by relative sea-level changes. CCA analysis reveal that hydrodynamic conditions are the primary influencing factor. Variation trends in average tiering and motility reveal the characteristics of biological communities during environmental changes in phylloid algae and microbial bioconstructions. These bioconstructions are not directly correlated with changes in environmental factors, and the biological communities in phylloid algae mounds and biostromes exhibit similar organism compositions and ecological niches across different environments. [ABSTRACT FROM AUTHOR]

Liaoceratops is a small basal neoceratopsian dinosaur from the Early Cretaceous Jehol Biota of western Liaoning, China. Because its postcranial skeleton is lacking, its behaviour and palaeoecology remain poorly understood. By using computed tomography (CT), we reconstructed the cranial endocast and endosseous labyrinths of an adult individual of Liaoceratops yanzigouensis (PMoL-AD00097). Analysis and comparisons indicate that the brain, olfactory bulb and inner ear of adult Liaoceratops more closely resemble those observed in adult specimens of the basal ceratopsian Psittacosaurus than those in more derived ceratopsians. The relatively large olfactory bulb, discernible floccular lobes, and relatively long semicircular canals suggest that the adult Liaoceratops had a keen sense of smell, a well-developed sensory input for the reflexive stabilisation of gaze and posture, and a nearly horizontal head posture. Based on its relatively short cochlear ducts, adult Liaoceratops likely vocalised at and heard more efficiently to relatively high frequencies than the derived ceratopsian Pachyrhinosaurus and Triceratops. The relatively well-developed semicircular canals suggest that adult Liaoceratops was agile biped and had a similar locomoter mode with adult Psittacosaurus. [ABSTRACT FROM AUTHOR]

The study of the palaeoenvironment of the Early Cretaceous has been a significant research topic, largely due to the "Jehol Biota" in western Liaoning and the important prospect of fossils in Dakangpu Layer. Based on the sedimentology of Dakangpu Layer, it is helpful to get a deeper understanding of the living environment of the "Jehol Biota." Varves are highly developed in the Dakangpu Bed of lower Cretaceous Yixian Basin in western Liaoning, China, supplying reliable and high‐quality proxies to explore the palaeoclimate. This paper reconstructs the palaeo‐lake environment and palaeoclimate, using petrography, facies associations, varves components, and geochemistry. Detailed petrographic studies helped to recognize 11 lithofacies which were grouped into two facies associations: Shallow lake and deep to semi‐deep lake sequences. The delicate structure of varves in the Dakangpu Bed were divided into two categories: Clastic and endogenic. Additionally, two sub‐types of clastic varves have been discovered, with distinct components, thickness, and distribution in vertical sequence. Nineteen representative samples of varves reveal that rare earth and trace elements have a similar change trend. The composition, formation, and preservation of the varves in the Dakangpu Bed depicted a deep lake, with stratified water and oxygen‐depleted bottom layer environment. The U/Th ratios and V/Cr ratios are in the ranges of 0.37–1.55 and 0.97–10.47 respectively, supporting the redox environment's minor fluctuation. The varve thickness, flood frequency, sporopollenin collections, and geochemical data indicated that precipitation and humidity decreased gradually in the sedimentary period, and the climate changed to warmer and drier, with fluctuations in the middle to later periods. [ABSTRACT FROM AUTHOR]