Redox control in arsenic accumulation with organic matter derived from a varved lacustrine deposit in the Jurassic accretionary complexes.

Oxidation states and distribution of arsenic (As) in annually laminated (varved) lacustrine deposits were analyzed with a seasonal resolution. This deposit was formed in the mid-Holocene landslide-dammed paleolake in the upper reaches of the Ane River, central Japan and the paleolake watershed consists of the Jurassic accretionary complexes (Mino-Tamba belt) including sedimentary and igneous rocks. In the outcrop, centimeter-to-decimeter-scale silty clay layers alternating with laminated layers are well developed.

Delayed increase in stone tool cutting-edge productivity at the Middle-Upper Paleolithic transition in southern Jordan.

Although the lithic cutting-edge productivity has long been recognized as a quantifiable aspect of prehistoric human technological evolution, there remains uncertainty how the productivity changed during the Middle-to-Upper Paleolithic transition. Here we present the cutting-edge productivity of eight lithic assemblages in the eastern Mediterranean region that represent a chrono-cultural sequence including the Late Middle Paleolithic, Initial Upper Paleolithic, the Early Upper Paleolithic, and the Epipaleolithic. The results show that a major increase in the cutting-edge productivity does not coincide with the conventional Middle-Upper Paleolithic boundary characterized by the increase in blades in the Initial Upper Paleolithic, but it occurs later in association with the development of bladelet technology in the Early Upper Paleolithic.

Forelimb muscle activation patterns in American alligators: Insights into the evolution of limb posture and powered flight in archosaurs.

The evolution of archosaurs provides an important context for understanding the mechanisms behind major functional transformations in vertebrates, such as shifts from sprawling to erect limb posture and the acquisition of powered flight. While comparative anatomy and ichnology of extinct archosaurs have offered insights into musculoskeletal and gait changes associated with locomotor transitions, reconstructing the evolution of motor control requires data from extant species. However, the scarcity of electromyography (EMG) data from the forelimb, especially of crocodylians, has hindered understanding of neuromuscular evolution in archosaurs.

The anatomy and feeding mechanism of the Japanese giant salamander (Andrias japonicus).

The fully aquatic Japanese giant salamander (Andrias japonicus) is a member of the Cryptobranchidae, and is currently distributed in western Japan, with other members of this group restricted to China and North America. Their feeding behaviour is characterized by a form of suction feeding that includes asymmetric movements of the jaw and hyobranchial apparatus. Previous studies on the North American species, Cryptobranchus alleganiensis, have suggested that this specialized jaw movement is produced by a flexible quadrate-articular joint combined with a loosely connected lower jaw symphysis including two small fibrocartilaginous pads.

Reproductive interference between alien species in Veronica.

Reproductive interference can lead to the exclusive distribution of species. Reports on reproductive interference between alien species are scarce, although alien species are becoming more abundant and evaluations of the interference between aliens and its influence on community structure are essential. We therefore investigated the presence of interference in two alien species of Veronica, V.

Fossorial mammals emphasise the forelimb muscle moment arms used for digging: New indices for reconstruction of the digging ability and behaviours in extinct taxa.

Among fossorial mammals, forelimbs are major digging apparatuses for dwelling, sheltering and foraging underground. Forelimb-diggers have independently evolved in many lineages of mammals; thus, the method of digging with forelimbs varies by taxon. Therefore, the reconstruction of digging behaviours in extinct animals leads us to understand the evolutionary process of fossorial adaptation in each lineage.

Decadal-centennial-scale solar-linked climate variations and millennial-scale internal oscillations during the Early Cretaceous.

Understanding climate variability and stability under extremely warm 'greenhouse' conditions in the past is essential for future climate predictions. However, information on millennial-scale (and shorter) climate variability during such periods is scarce, owing to a lack of suitable high-resolution, deep-time archives. Here we present a continuous record of decadal- to orbital-scale continental climate variability from annually laminated lacustrine deposits formed during the late Early Cretaceous (123-120 Ma: late Barremian-early Aptian) in southeastern Mongolia.

Coracoid strength as an indicator of wing-beat propulsion in birds.

Birds generate a propulsive force by flapping their wings. They use this propulsive force for various locomotion styles, such as aerodynamic flight, wing-paddle swimming and wing-assisted incline running. It is therefore important to reveal the origin of flapping ability in the evolution from theropod dinosaurs to birds.

A globally distributed durophagous marine reptile clade supports the rapid recovery of pelagic ecosystems after the Permo-Triassic mass extinction.

Marine ecosystem recovery after the Permo-Triassic mass extinction (PTME) has been extensively studied in the shallow sea, but little is known about the nature of this process in pelagic ecosystems. Omphalosauridae, an enigmatic clade of open-water durophagous marine reptiles, potentially played an important role in the recovery, but their fragmentary fossils and uncertain phylogenetic position have hindered our understanding of their role in the process. Here we report the large basal ichthyosauriform Sclerocormus from the Early Triassic of China that clearly demonstrates an omphalosaurid affinity, allowing for the synonymy of the recently erected Nasorostra with Omphalosauridae.

Anatomy informs geology: Hydrodynamic dispersal of alligator bones, with implications for taphonomic interpretations of fossil deposits of crocodylians, dinosaurs, and other morphologically novel taxa.

Distinctive anatomical features of bones can influence not only how these structures perform in living animals but also the tendency of elements to be transported by flowing water after death. Such transport can be critical in the concentration of fossils from animals that live near freshwater habitats, providing important context for interpreting the composition of paleocommunities. Measurements of the tendency of flowing water to disperse skeletal elements have been collected for diverse taxa, including mammals, turtles, and birds.

An intermediate crocodylian linking two extant gharials from the Bronze Age of China and its human-induced extinction.

A solid phylogenetic framework is the basis of biological studies, yet higher level relationships are still unresolved in some major vertebrate lineages. One such group is Crocodylia, where the branching pattern of three major families (Alligatoridae, Crocodylidae and Gavialidae) has been disputed over decades due to the uncertain relationship of two slender-snouted lineages, gavialines and tomistomines. Here, we report a bizarre crocodylian from the Bronze Age of China, which shows a mosaic of gavialine and tomistomine features across the skeleton, rendering support to their sister taxon relationship as molecular works have consistently postulated.

Feeding behaviour and functional morphology of the neck in the long-snouted aquatic fossil reptile Champsosaurus (Reptilia: Diapsida) in comparison with the modern crocodilian Gavialis gangeticus.

The extinct freshwater choristoderan reptiles Champsosaurus and Simoedosaurus are characterised by large body size and an elongated snout. They have often been considered as eco-analogues of crocodilians based on superficial similarities. The slender-snouted Champsosaurus has been described as a 'gavial-like reptile', which implies it feeds underwater with a lateral swipe of the head and neck, as in the living slender-snouted crocodilians such as Gavialis gangeticus.

Ontogenetic changes in limb posture, kinematics, forces and joint moments in American alligators (Alligator mississippiensis).

As animals increase in size, common patterns of morphological and physiological scaling may require them to perform behaviors such as locomotion while experiencing a reduced capacity to generate muscle force and an increased risk of tissue failure. Large mammals are known to manage increased mechanical demands by using more upright limb posture. However, the presence of such size-dependent changes in limb posture has rarely been tested in animals that use non-parasagittal limb kinematics.

Structure and Absolute Configuration of Phenanthro-perylene Quinone Pigments from the Deep-Sea Crinoid .

Two new water-soluble phenanthroperylene quinones, gymnochrome H () and monosulfated gymnochrome A (), as well as the known compounds gymnochrome A () and monosulfated gymnochrome D () were isolated from the deep-sea crinoid , which had been collected in the deep sea of Japan. The structures of the compounds were elucidated by spectroscopic analysis including HRMS, 1D H and C NMR, and 2D NMR. The absolute configuration was determined by ECD spectroscopy, analysis of -couplings and ROE contacts, and DFT calculations.

Vertebrae-Based Body Length Estimation in Crocodylians and Its Implication for Sexual Maturity and the Maximum Sizes.

Body size is fundamental to the physiology and ecology of organisms. Crocodyliforms are no exception, and several methods have been developed to estimate their absolute body sizes from bone measurements. However, species-specific sizes, such as sexually mature sizes and the maximum sizes were not taken into account due to the challenging maturity assessment of osteological specimens.

Stable isotope evidence of human diet in Mediterranean context during the Last Glacial Maximum.

The Final Gravettian in Europe overlapped with the cold and dry climatic event of Heinrich 2 (ca. 27-23.5 kyr cal BP), which caused the contraction of human distribution over refuge regions in the southern peninsulas of Europe.

Author Correction: Heavy reliance on plants for Romanian cave bears evidenced by amino acid nitrogen isotope analysis.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Heavy reliance on plants for Romanian cave bears evidenced by amino acid nitrogen isotope analysis.

Heavy reliance on plants is rare in Carnivora and mostly limited to relatively small species in subtropical settings. The feeding behaviors of extinct cave bears living during Pleistocene cold periods at middle latitudes have been intensely studied using various approaches including isotopic analyses of fossil collagen. In contrast to cave bears from all other regions in Europe, some individuals from Romania show exceptionally high δN values that might be indicative of meat consumption.

Author Correction: Fossilized Melts in Mantle Wedge Peridotites.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Habitat partitioning in native Geranium species through reproductive interference.

Background And Aims: Heterospecific pollen transfer may reduce the fitness of recipient species, a phenomenon known as reproductive interference. A theoretical study has predicted that distributions of species pairs affected by reproductive interference may be syntopic under negligible reproductive interference, sympatric but with partitioning at small spatial scale (i.e.

A protocol for using attenuated total reflection Fourier-transform infrared spectroscopy for pre-screening ancient bone collagen prior to radiocarbon dating.

Rationale: Pre-screening of bone collagen quality is important to reduce the cost for analyses such as radiocarbon ( C) dating with accelerator mass spectrometry in archaeological studies. We developed a pre-screening protocol based on attenuated total reflection (ATR) Fourier-transform infrared spectroscopy (FTIR) for assessing the chemical composition and mineralogy of ancient bone samples.

Methods: ATR-FTIR measurements were performed on bulk bones of diverse origin and age before collagen extraction.

The range of atlanto-occipital joint motion in cetaceans reflects their feeding behavior.

The cetaceans display a wide variety of lifestyles, especially with regard to their feeding behavior. However, the evolutionary process of the feeding behavior in cetaceans is still poorly understood, in part because reconstructing the feeding behavior of extinct taxa remains difficult. In cetaceans, cranium mobility relative to the trunk largely depends on the range of motion permitted by the atlanto-occipital joint, given the lack of flexibility of the cervical series.

Lithic technology, chronology, and marine shells from Wadi Aghar, southern Jordan, and Initial Upper Paleolithic behaviors in the southern inland Levant.

The Initial Upper Paleolithic (IUP) temporally overlaps with the range expansion of Homo sapiens populations in various parts of Eurasia and is often considered a key archaeological phase for investigating behavioral changes from the Middle Paleolithic. This paper reports upon new data from IUP occupations at Wadi Aghar, a rock shelter site in the southern Levant. In combining the results of radiometric dates and lithic analyses, we clarify the chronological and cultural position of Wadi Aghar assemblages in the Levantine IUP.