Search Results (329)

A newly discovered deposit on the bed of the Steinhatchee River produced a moderately diverse assemblage of 15 vertebrate taxa herein designated the Steinhatchee River 2A (STR 2A) local fauna. Mammalian taxa isotopically shown from other sites to be either grazers or grazing-dominated mixed-feeders numerically dominate the fauna, especially a species of Equus. About 75% of the 552 identifiable fossils from STR 2A, representing a minimum of nine individuals, are referred to the informally named Equus (Equus) sp. A. The site produced the first known examples of associated upper and lower cheekteeth and lower incisors for this species, and also one of just two records outside of central and southern peninsular Florida. Like most Pleistocene sites in Florida, xenarthrans are diverse, with two cingulates, Dasypus and Holmesina, and two pilosans, Paramylodon and Megalonyx. An astragalus and several metatarsals of Holmesina are within the size range of H. septentrionalis, but also have some characteristics found in the older species H. floridanus. These finds corroborate that an evolutionary transition between these two species occurred in Florida during the Irvingtonian. The age of STR 2A is most likely middle Irvingtonian, ca. 0.5–0.7 Ma, an interval poorly known in Florida and the rest of the southeastern USA. Full article

Understanding the relationship between modern pollen assemblages and vegetation/climate for various elevations is essential for accurately interpreting fossil pollen records and conducting quantitative climate reconstructions in mountainous regions. However, these relationships for the Tibetan Plateau, which is the highest and one of the most ecologically sensitive regions globally, are still scarce. We present modern pollen assemblages from 78 topsoil samples collected along altitudinal gradients from 498 to 4046 m above sea level on the eastern Tibetan Plateau. They were distributed in alpine shrub meadows, coniferous forests, and mixed broad-leaved and coniferous forest vegetation types. Multivariate statistical methods, including discriminant analysis, indicator species analysis, logistic regression, and redundancy analysis, were employed to identify relationships among modern pollen assemblages, vegetation types, and climate along an altitudinal gradient. The results revealed that (1) vegetation types along the altitudinal gradient can be effectively differentiated by comparing pollen assemblages, discriminant analysis, and indicator species analysis; (2) the conifer/broadleaf pollen ratio (C/B) efficiently distinguished coniferous forests (C/B > 5) from mixed forests (C/B < 5); and (3) variations in modern pollen assemblages are primarily influenced by temperature, with pollen ratios, such as Artemisia/Cyperaceae (Art/Cy) and Tsuga/(Tsuga + Abies + Picea) (T/TAP), displaying notable altitudinal and temperature differences. These findings demonstrate that variations in modern pollen assemblages on the eastern Tibetan Plateau differentiate between vegetation types and correlate with temperature variations associated with elevation. The results provide insights for future paleovegetation and paleoclimatic reconstructions for similar mountainous regions. Full article

Clam shrimps are one of the most common and representative invertebrates in continental strata and are endowed with important biostratigraphic and paleoecological values. The genus Euestheria is one of the most common clam shrimp taxa that has been recorded in the latest Paleozoic and the Mesozoic around the world. A list of all the species assigned to Euestheria, recorded from the Devonian to the Cretaceous across all seven continents as of September 2024, is provided. The list may serve as a valuable resource, potentially useful for the biostratigraphic division and long-range correlations of continental strata. In addition, the taxonomic issues of the genus are briefly introduced and examined herein. The study aims to provide a simple lead-in for all the researchers who have an interest in clam shrimp and the genus Euestheria. Full article

The two basic approaches to elucidating how life began both date from Darwin. The first, that of the experimentalists, stems from Darwin’s famous “warm little pond” letter to Joseph Hooker of 1871. This approach, an attempt to replicate the sequential events leading to life’s origin, is exemplified by the “primordial soup” hypothesis of A.I. Oparin (1924) and J.B.S. Haldane (1929); the Miller–Urey laboratory synthesis of amino acids under possible primitive Earth conditions (1953); and Joan Oró’s nonbiological synthesis of the nucleic acid adenine (1959). The second approach, that of the observationalists who search for relevant evidence in the geological record, dates from Darwin’s 1859 On the Origin of Species, in which he laments the “inexplicable” absence of a pre-Cambrian fossil record. Darwin’s concern spurred a century of search that was ultimately rewarded by Stanley Tyler’s 1953 discovery of diverse microscopic fossils in the ~1900 Ma Gunflint Chert of southern Canada. Tyler’s find was soon followed by a cascade of discoveries worldwide; the establishment of a new field of science, Precambrian paleobiology; and, more recently, the discovery of 3400 and ~3465 Ma Paleoarchean microfossils, establishing that primordial life evolved early, far, and fast. Though progress has been made, much remains to be learned in the foci of this Origin of Life 2024 volume, for which this essay is the history-reviewing “stage setter”. Full article

Recent investigations in the upper Lower–Middle Pleistocene deposits of the Megalopolis Basin (Greece) led to the discovery of several sites/findspots with abundant faunal material. Here, we provide an updated overview including new results on the micro- and macro-mammal fauna. Important new discoveries comprise partial hippopotamus skeletons from Marathousa 1 and the new Lower Pleistocene site Choremi 6, as well as a second partial elephant skeleton from Marathousa 1, including a complete tusk and the rarely found stylohyoideum. Based on the first results from the newly collected micromammals, we discuss age constraints of the sites, and we provide biostratigraphic/biochronologic remarks on key mammal taxa for the Middle Pleistocene of Greece and southeastern Europe. The presence of mammals highly dependent on freshwater for their survival, together with temperate-adapted ones in several stratigraphic layers of the basin, including those correlated with glacial stages, when conditions were colder and/or drier, indicate the capacity of the basin to retain perennial freshwater bodies under milder climatic conditions, even during the harsher glacial periods of the European Middle Pleistocene, and further support its refugial status. Yet, the smaller dimensions of the Megalopolis hippopotamuses may represent a response to the changing environmental conditions of the epoch, not optimal for hippopotamuses. Overall, the Megalopolis Basin comprises a unique fossil record for southeastern Europe and provides valuable insights into the Middle Pleistocene terrestrial ecosystems of Europe, and hominin adaptations in particular. Full article

Styracosternan ornithopods are plenty abundant in the Lower Cretaceous fossil record of Europe. In particular, Iguanodon, the second genus of dinosaurs described worldwide, has been found in UK, Belgium, France, Germany, and Spain, evidencing a wide geographical distribution. Currently, the genus Iguanodon comprises two species, the type species I. bernissartensis from the late Barremian–Aptian of Europe and I. galvensis from the early Barremian of Teruel, Spain. The latter species is well known mainly from perinate and juvenile specimens. Here, axial and appendicular fossils of an adult, large and massively constructed ornithopod from the lower Barremian (Lower Cretaceous) Camarillas Formation of Galve (province of Teruel, Spain) are described. Fossil dimensions and some osteological evidence reveal that the specimen was a large (roughly 10 m long) ornithopod. An autapomorphic feature in the ischium and other characters allow us to ascribe this specimen to I. galvensis. In addition, postcranial co-ossification and fusion of the neurocentral suture indicate that the specimen was skeletally mature. Part of the material studied here was unknown in adults of I. galvensis, providing a better knowledge of the axial and appendicular region of this species. Full article

Uruguayan ammonoids are preserved in phosphate and siderite nodules found at the basalmost tillite-like conglomerates of the San Gregorio Formation. This lithostratigraphic unit was deposited under glacial conditions and its age (as well as that of the nodules) has been highly debated because glaciations were intermittent in Gondwana during the Late Paleozoic. Reef-builder organisms (e.g., Rugosa and Tabulata), goniatite and orthoceratid cephalopods, brachiopods, sponges, actinopterygians and other indeterminate gnatostomes, as well as fragmentary stems and roots of cf. Lycopsida are the most frequent fossils in the nodules. According to new biostratigraphic and paleoclimatic evidence, these taxa are representative of a reefal environment of a preliminary Devonian age including species that are common in the underlying Early Devonian (Emsian) Durazno Group. Among the ammonoid remains, more than 40 clusters of hatchling goniatites were found in the nodules. Each cluster contains a variable number of shells similar in shape to some of the adults also preserved within the nodules, representing a single species preserved at the same developmental stage (3 mm on size average). The strongly packed shells are enveloped by a substance with a different chemical composition and microstructure with respect to that of the nodule matrix, possibly indicating the presence of a gelatinous-like substance reminiscent of that secreted by the females of some extant cuttlefish and octopuses at the time of the egg spawn. Differing from previously described ammonoid accumulations, our clusters are unique in containing individuals of just a single species preserved in the same ontogenetic stage. That allows us to suggest that they represent a mode of reproduction in which hatchlings were morphologically similar to their parents and occupied the same habitat. Our results are thus one of the oldest known records of reproductive strategies in Paleozoic ammonoids and the phosphate and siderite nodules from the San Gregorio Formation are here classified as a new Konservat-Lagerstätte, which is the oldest known for South America. Full article

Long-standing, continuous blurring and controversies in the field of phylogenetic interspecies relations, associated with insufficient explanations for dynamics and variability of speeds of evolution in mammals, hint at a crucial missing link. It has been suggested that transgenerational epigenetic inheritance and the concealed mechanisms behind play a distinct role in mammalian evolution. Here, a comprehensive sequence alignment approach in hominid species, i.e., Homo sapiens, Homo neanderthalensis, Denisovan human, Pan troglodytes, Pan paniscus, Gorilla gorilla, and Pongo pygmaeus, comprising conserved CpG islands of housekeeping genes, uncover evidence for a distinct variability of CpG dinucleotides. Applying solely these evolutionary consistent and inconsistent CpG sites in a classic phylogenetic analysis, calibrated by the divergence time point of the common chimpanzee (P. troglodytes) and the bonobo or pygmy chimpanzee (P. paniscus), a “phylo-epigenetic” tree has been generated, which precisely recapitulates branch points and branch lengths, i.e., divergence events and relations, as they have been broadly suggested in the current literature, based on comprehensive molecular phylogenomics and fossil records of many decades. It is suggested here that CpG dinucleotide changes at CpG islands are of superior importance for evolutionary developments. These changes are successfully inherited through the germ line, determining emerging methylation profiles, and they are a central component of transgenerational epigenetic inheritance. It is hidden in the DNA, what will happen on it later. Full article

A new fossil gray whale genus and species, Glaucobalaena inopinata, is established based on craniomandibular remains from the Pliocene Sabbie d’Asti Formation, Piedmont, northwestern Italy. The holotype (MGPT-PU 19512) consists of two cranial fragments corresponding to the posterolateral corners of the skull, including both partial periotics, and in the posterior portion of the right mandibular ramus preserving the condyle and angular process. The new taxon is characterized by gray whale (eschrichtiid) synapomorphies in the posterior portion of the mandible (dorsally raised mandibular condyle with articular surface faced dorsoposteriorly, well-developed and robust angular process of the mandible) and in the earbone (massive transverse elongation of the pars cochlearis, indistinct flange of the ventrolateral tuberosity, and triangular and short anterior process of the periotic). A CT scan of the cranial fragments allowed us to reconstruct tridimensional renderings of the periotic, revealing the dorsal morphology of this bone. A phylogenetic analysis confirmed the inclusion of Glaucobalaena inopinata within Eschrichtiidae (the family to whom gray whales are included) and showed that it is monophyletic with Gricetoides aurorae; our phylogenetic results show that Eschrichtioides gastaldii is the sister group of the genus Eschrichtius. Our work lends further support to the idea that Eschrichtiidae is a separate family of baleen whales, characterized by specialized ecomorphological characters evident in both skull and mandibular architecture. Full article

The Ediacaran of eastern Newfoundland preserves the world’s oldest known eumetazoan body fossils, as well as the earliest known record of fossilized muscular tissue. Re-examination of the holotype of the eight-armed Haootia quadriformis in terms of its morphology, the arrangement of its muscle filament bundles, and hitherto undescribed aspects of its anatomy support its interpretation as a crown staurozoan. We also document several new fossils preserving muscle tissue with a different muscular architecture to Haootia, but with only four arms. This new material allows us to describe a new crown group staurozoan, Mamsetia manunis gen. et sp. nov. This work confirms the presence of crown group medusozoan cnidarians of the Staurozoa in the Ediacaran of Newfoundland circa 565 Ma. Full article

A new stag beetle fossil, Prostreptocerus burmiticus Yu & Cai gen. et sp. nov., is described based on a single male specimen. This is the first representative of the subfamily Lampriminae (Coleoptera: Scarabaeoidea: Lucanidae) from mid-Cretaceous Burmese amber. The new species is distinctive among Lucanidae due to its well-developed, right-angled mandible, frons featuring a pair of large protuberances, a coarse and sparsely punctate elytral disc, and large tubercles on the humeri. Prostreptocerus Yu & Cai is placed within Lampriminae based on several key characteristics. Morphologically, it is most similar to the extant Streptocerus Fairmaire, 1850. The current distribution of Streptocerus and Lampriminae is primarily restricted to the Southern Hemisphere, suggesting that this lineage is ancient and existed on Gondwanaland, which has significant geographical implications. This discovery extends the fossil record of Lampriminae and provides additional evidence for the existence of sexual dimorphism and potential combat behavior in Mesozoic lucanids. Additionally, Electraesalopsis Bai, Zhang & Qiu, 2017, previously placed as Lucanidae incertae sedis, shares many characteristics with Prostreptocerus Yu & Cai and is also assigned to Lampriminae based on a suite of traits. Full article

The life quality of populations, especially in large agglomerations, is significantly reduced due to air pollution. Major sources of pollution include motor vehicles, industrial facilities and the burning of fossil fuels. A particularly significant source of pollution is thermal power plants and coal-fired power plants, which are widely used in developing countries. The Astana city in the Republic of Kazakhstan is a fast-growing agglomeration where air pollution is compounded by intensive construction and the use of coal for heating. The research is important for the development of urbanism in terms of ensuring the sustainable development of urban agglomerations, which are growing rapidly. Long memory in time series of concentrations of air pollutants (particulate matter PM10, PM2.5) from four stations in Astana using the fractal R/S analysis method was studied. The Hurst exponents for the studied stations are 0.723; 0.548; 0.442 and 0.462. In addition, the behavior of the Hurst exponent in dynamics is studied by the flow window method based on R/S analysis. As a result, it was found that the pollution indicators of one of the stations are characterized by the presence of long-term memory and the time series is persistent. According to the analysis of recordings from the second station, the series is defined as close to random, and for stations 3 and 4, anti-persistence is characteristic. The calculated Hurst exponent values explain the sharp increase in pollution levels in October 2021. The reason for the increase in polluting substances concentration in the air is the close location of thermal power plants to the city. The method of time series fractal analysis can be the ecological state indicator in the corresponding region. Persistent pollution time series can be used to predict the occurrence of a critical pollution level. One of the reasons for anti-persistence or the occurrence of a temporary contamination level may be the close location of the observation station to the source of contamination. The obtained results indicate that the fractal time series analysis method can be an indicator of the ecological state in the relevant region. Full article

Bifacial solar modules, capable of harvesting sunlight from both sides, present a promising pathway for sustainable energy generation. This study examines the performance of bifacial modules on a cloudy day through comparative exergy and energy analyses. The analysis considers both the quality and quantity of energy produced by bifacial and monofacial modules. Conducted at Qassim University in Buraydah City, Saudi Arabia, the study recorded measurements during two intervals on a cloudy day using a real-time photovoltaic measurement system. Module performance was evaluated concerning energy yield, exergy yield, and solar irradiance, factoring in ambient and module temperatures. The results demonstrate that bifacial modules outperformed monofacial modules in electrical energy and output exergy. In the first period, the bifacial modules showed a 9.5% higher exergy efficiency and a 7% greater energy efficiency compared to the monofacial modules. During the second period, the bifacial modules achieved a 4.5% higher exergy efficiency and a 3.5% increased energy efficiency over the monofacial modules. These findings contribute to global sustainability efforts by reducing fossil fuel dependence and optimizing bifacial PV module design and operation for enhanced energy and exergy efficiency, even in cloudy conditions. The study’s implications for sustainable development and energy policies underscore the essential role of advanced PV technologies in achieving sustainable energy goals. Full article

The Early Pleistocene sites of Orce in southeastern Spain, including Fuente Nueva-3 (FN3), Barranco León (BL) and Venta Micena (VM), provide important insights into the earliest hominin populations and Late Villafranchian large mammal communities. Dated to approximately 1.4 million years ago, FN3 and BL preserve abundant Oldowan tools, cut marks and a human primary tooth, indicating hominin activity. VM, approximately 1.6 million years old, is an outstanding site because it preserves an exceptionally rich assemblage of large mammals and predates the presence of hominins, providing a context for pre-human conditions in the region. Research suggests that both hominins and giant hyenas were essential to the accumulation of skeletal remains at FN3 and BL, with secondary access to meat resources exploited by saber-toothed felids. This aim of this study aims to correlate the relative abundance of large herbivores at these sites with their estimates of Carrying Capacity (CC) and Total Available Biomass (TAB) using the PSEco model, which incorporates survival and mortality profiles to estimate these parameters in paleoecosystems. Our results show: (i) similarities between quarries VM3 and VM4 and (ii) similarities of these quarries with BL-D (level D), suggesting a similar formation process; (iii) that the role of humans would be secondary in BL-D and FN3-LAL (Lower Archaeological Level), although with a greater human influence in FN3-LAL due to the greater presence of horses and small species; and (iv) that FN3-UAL (Upper Archaeological Level) shows similarities with the expected CC values for FN3/BL, consistent with a natural trap of quicksand scenario, where the large mammal species were trapped according to their abundance and body mass, as there is a greater presence of rhinos and mammoths due to the greater weight per unit area exerted by their legs. Given the usefulness of this approach, we propose to apply it first to sites that have been proposed to function as natural traps. Full article

The Croatian Natural History Museum (CNHM) houses rich fossil collections from the Neogene deposits of Northern Croatia, comprising numerous scallops (Bivalvia: Pectinidae). During the Middle Miocene (Badenian = Langhian and early Serravallian), this region was located at the southwestern margin of the Central Paratethys. The value of the CNHM’s historical collections has been presented through taxonomic revisions and biostratigraphic, paleoenvironmental and paleogeographic study. Methods included the cross-checking of specimens from museum boxes with all available published data, systematic revision of scallops, recording the abundance of each taxon, defining the preservation state of the specimens, measuring the morphometric elements and taking photographs of each specimen. After the conducted revision of 624 specimens, the number of registered taxa in the collections was reduced from 52 to 33, and their stratigraphic distribution has been updated. The species Lissochlamys excisa (Bronn, 1831) has been recorded for the first time at the southwestern part of the Central Paratethys. The southernmost Badenian record of Delectopecten vitreus (Gmelin, 1791) known so far has been described. Six types of pectinid habitats have been distinguished, based on the provided paleontological and lithological data, also estimating the scallops’ abundance in each of them. Bioerosion and encrustation traces on scallops’ shells represent an additional contribution to paleoecological studies. Full article