Search Results (81)

The movement of valves of bivalved invertebrates is enabled through the action of muscles and the interplay between the muscles and the hinge ligament. The muscles that move the valves attach to their internal surface. To promote the structural integrity at the mechanically mismatched interfaces, a specific crystal microstructure and texture are present at the muscle attachment sites. These are different from the crystal microstructure and texture of the rest of the valves. We present here for modern two- and three-layered brachiopod shells (Magellania venosa, Liothyrella neozelanica and Gryphus vitreus) the mode of crystal organisation at sites of adductor and diductor muscle attachments (i) relative to the microstructure and texture that forms the other sections of the valves and (ii) relative to crystal organisation of muscle attachment sites of bivalved invertebrates of other phyla, namely, species of the class Bivalvia. We discuss similarities/differences in Ca-carbonate phase, microstructure and texture between rhynchonellate brachiopods and bivalves, and discuss whether the Ca-carbonate crystal organisation of muscle attachment sites is convergent for bivalved marine organisms. We show significant differences in muscle attachment site architecture and highlight the different structural solutions developed by nature for shells of marine organisms that serve the same purpose. Full article

Representatives of Dermestidae (skin, larder, and carpet beetles) play a crucial role as decomposers in global ecosystems, facilitating the recycling of animal and plant biomass to sustain nutrient cycling. Despite their widespread ecological presence and functional importance, the fossil record of their larval stages has remained sparse, with previous documentation limited to occasional discoveries. This study significantly expands the larval fossil record by identifying 36 amber-preserved specimens from the Cretaceous, Eocene, and Miocene time slices, obtained from deposits distributed globally. By challenging the historical view of larval fossil rarity, we reveal morphological changes in defensive setae over geological time, demonstrating that Cretaceous and later fossil larvae possess significantly longer absolute and relative setal lengths compared to their extant counterparts. These findings, bolstered by quantitative comparisons of setal and body dimensions across fossil and extant representatives, indicate evolutionary adaptations in defensive structures dating back at least 100 million years. Our results offer new insights into the paleobiology of the group Dermestidae, highlighting how the morphology of larvae potentially reflects historical ecological pressures and resources availability. This study emphasizes the importance of integrating fossil evidence with comparative morphology to elucidate the evolutionary trajectories and functional roles of larvae in ancient terrestrial ecosystems. Full article

For decades, thousands of scientific institutions worldwide have been digitizing collections documenting biodiversity. The advantages and benefits of this process are widely described. In this study, we test the hypothesis that digital data from local scientific institutions gain additional value once shared through the Global Biodiversity Information Facility (GBIF). We have closely examined the fate of over 2.2 million digital records deposited at the Faculty of Biology, Adam Mickiewicz University in Poznań, Poland (FBAMU), which have been available to the global community for over three years. The effectiveness of this effort is measured by the number of downloads (approximately 123,000), the number of records downloaded (45 billion), and most importantly, the number of scientific publications utilizing these data (an average of 3 publications per week). These publications appear both in the most prestigious scientific journals and regional sources. The thematic scope of papers utilizing FBAMU data shared through GBIF is very broad, covering 12 research areas, including fundamental biological fields (morphology, taxonomy and systematics, phylogeny and evolution, paleobiology, ecology, biogeography, biodiversity conservation, and biodiversity informatics), closely related applied research (agriculture and human health), and climate science and linguistic phylogeny. The most frequent uses of GBIF/FBAMU data have been in studies on processes and phenomena such as biodiversity loss, biological invasions, biogeographical patterns, changes in species ranges, climatic niche dynamics, interactions between organisms, and mechanisms of evolution. Full article

The preservation of paleontological heritage is relevant for paleobiological and geological research, as well as for scientific dissemination. Fossils are indicative of the evolutionary processes, biodiversity, ecology, and geography of the past and require specific geoconservation actions. In Italy, fossils are protected as cultural heritage, and their unauthorized collection and trading are counteracted by a regulatory framework. The local superintendence and law enforcement provide control over the territory, often resorting to the expertise of university paleontologists. In the Calabria region (southern Italy), the collaboration among institutions is yielding interesting results in research, preservation, and public awareness of paleontological heritage. This paper highlights the different approaches to the conservation and promotion of fossils by three museums in Calabria. At the National Archeological Museum of Reggio Calabria, fossils are included in the Prehistory section. The history of life on Earth, with a focus on regional paleontology, characterizes the Museum of the University of Calabria. The Civic Museum of Ricadi exhibits local fossils. Collaboration among these museums and their institutional referents contributes to public awareness and scientific understanding of paleontological heritage, reinforcing the need for conservation and promotion strategies. Full article

Extinct flightless birds of the clades Phorusrhacidae and Brontornithidae are among the most characteristic elements of the South American Cenozoic faunas. Although the anatomy, systematics, paleoecology, and distribution of these birds have been analyzed in some detail, there is not a single work dealing with the osteohistology of these taxa. Herein, we present for the first time paleohistological data for phorusrhacids (Patagornis marshi) and brontornithids (Brontornis burmeisteri). A dense vascularized fibrolamellar matrix and an uninterrupted cortex lacking growth lines indicate similar metabolism and physiological attributes occurring in most extant birds, and they differ from the condition of insular taxa or species living in very stable habitats. This is congruent with recent analyses indicating that phorusrhacids were very active birds lacking insularity-related attributes. It also supports recent growing evidence indicating that these birds’ extinction may be related to climatic and environmental changes rather than being the result of competitive displacement by immigrant placental mammals. Full article

One new genus and five new species of the extinct family Maimetshidae from mid-Cretaceous Kachin amber are described based on five well-preserved specimens as follows: Maimetshasia nova Li, Kopylov and Rasnitsyn, sp. nov.; Maimetshasia engeli Li, Kopylov and Rasnitsyn, sp. nov.; Guyotemaimetsha perrichoti Li, Kopylov and Rasnitsyn, sp. nov.; Guyotemaimetsha ortegablancoi Li, Kopylov and Rasnitsyn, sp. nov.; and Crucimaimetsha nigra Li, Kopylov and Rasnitsyn, sp. nov. A new generic synonymy is proposed: Turgonalus Rasnitsyn, 1990 (=Turgonaliscus Engel, 2016, syn. nov. and = Ahiromaimetsha Perrichot, Azar, Nel and Engel, 2011, syn. nov.); Guyotemaimetsha Perrichot, Nel and Néraudeau, 2004 (=Burmaimetsha Perrichot, 2013, syn. nov.); Afrapia, Rasnitsyn and Brothers, 2009 (=Afromaimetsha, Rasnitsyn and Brothers, 2009, syn. nov.); and Iberomaimetsha nihtmara Ortega-Blanco, Delclòs and Engel, 2011 are transferred to Afrapia, Rasnitsyn and Brothers, 2009. This results in the following new combinations: Turgonalus cooperi, Rasnitsyn and Jarzembowski, 1998, comb. resurr.; Turgonalus najlae (Perrichot, Azar, Nel & Engel, 2011), comb. nov; Afrapia robusta (Rasnitsyn & Brothers, 2009), comb. nov; and Afrapia nihtmara (Ortega-Blanco, Delclòs & Engel, 2011), comb. nov. The occurrence of various genera of Maimetshidae in amber and compression fossil and the morphological differences of the forewings in all the fossil species are provided, which highlights a high level of genus-level diversity among Mesozoic maimetshids. The key to genera was updated. Full article

Primate species differ drastically from most other mammals in how they visually perceive their environments, which is particularly important for foraging, predator avoidance, and detection of social cues. Background/Objectives: Although it is well established that primates display diversity in color vision and various ecological specializations, it is not understood how visual system characteristics and ecological adaptations may be associated with gene expression levels within the primary visual cortex (V1). Methods: We performed RNA-Seq on V1 tissue samples from 28 individuals, representing 13 species of primates, including hominoids, cercopithecoids, and platyrrhines. We explored trait-dependent differential expression (DE) by contrasting species with differing visual system phenotypes and ecological traits. Results: Between 4–25% of genes were determined to be differentially expressed in primates that varied in type of color vision (trichromatic or polymorphic di/trichromatic), habitat use (arboreal or terrestrial), group size (large or small), and primary diet (frugivorous, folivorous, or omnivorous). Conclusions: Interestingly, our DE analyses revealed that humans and chimpanzees showed the most marked differences between any two species, even though they are only separated by 6–8 million years of independent evolution. These results show a combination of species-specific and trait-dependent differences in the evolution of gene expression in the primate visual cortex. Full article

This is the first record of the biggest Metriorhynchidae, aff. Plesiosuchus sp. in France. The remains consist of a partial vertebral column consisting of 11 vertebrae and an ischium fragment. A new method is proposed to evaluate the individual’s size, which is estimated at 6.5 m. This method, unlike previous approaches, is based only on vertebrae and yields results that are congruent with those based on cranial remains. The state of preservation has allowed us to test the animal’s ‘profile of locomotion’ to better interpret how it moved. Concerning other metriorhynchids, the record of Dakosaurus in France based only on teeth must be reassessed, and the genus Torvoneustes, if valid, has to be distinguished from Plesiosuchus. Full article

Two brachiopod species, Terebratulina tenuistriata (Leymerie, 1846) and Orthothyris pectinoides (von Koenen, 1984), have been recorded for the first time from the Middle Eocene (Late Lutetian) nummulitic limestone beds in the Darnah Formation at the Wadi Darnah area in Northeast Libya. These brachiopod species are associated here with Nummulites discorbinus (Schlotheim), Nummulites praelyelli (Boukhary and Kamal), and Nummulites bullatus (Schaub) and are widely distributed on this Middle Eocene Nummulites carbonate platform. The two recorded species are common in the Eocene rocks of Europe and the Arabian Gulf. In northern Africa, the brachiopod species Terebratulina tenuistriata (Leymerie) was only recorded from the Middle Eocene (Bartonian) of Egypt, while Orthothyris pectinoides (von Koenen) is firstly recorded from the Middle Eocene of the southern Tethyan Province (NE Libya) in the present work. 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

Ceratitis capitata (Wiedemann) (medfly) strongly affects Argentinean fruit production and export. Augmentative biological control using the exotic parasitoid Diachasmimorpha longicaudata (Ashmead) is currently applied to this problem. The ability to find and parasitize medfly larvae on a wide diversity of fruit host species is a key issue that needs to be analyzed. This research assessed the effect of the physical features of fruit on the preference of foraging D. longicaudata females and the influence of varying release density on parasitoid performance as a pest mortality factor in three fruit species. Trials were performed inside field cages under semi-arid environmental conditions in Argentina’s central-western fruit-growing region. Sweet orange, peach, and fig were tested. The fruits were inoculated with third-instar larvae of the Vienna-8 temperature-sensitive lethal medfly strain. Naïve, 5 d-old mated D. longicaudata females were released in cages at 20, 40, 80, and 160 parasitoid densities. The highest levels of medfly mortality and parasitoid emergence were recorded in fig and peach, although D. longicaudata also induced mortality in orange, a fruit with few physical features favorable to parasitism. The medfly mortality in all fruit host species significantly increased with an increased number of parasitoid females released into the field cages. Diachsmimorpha longicaudata has high potential as a medfly biocontrol agent. Full article

In paleobiology and macroevolution research, the spatial aggregation of fossil data can be influenced by the modifiable areal unit problem (MAUP), wherein the selection of different grid-cell sizes for data aggregation can lead to variations in statistical results. This study presents a case analysis focused on the spatial extent of marine bivalves and brachiopods over time across three Areas of Interest (AOIs) to evaluate the potential impact of the MAUP in grid-based fossil data processing. By employing rectangular grid matrices with cell sizes of 50, 100, 200, and 400 km, this research assesses the MAUP-related sensitivity of two commonly used grid-based proxies for species’ spatial distribution. The results reveal that the proxy based on the number of occupied grid cells (OGCs) is particularly sensitive to changes in cell size, whereas the proxy based on minimum-spanning-tree distance (MST distance) demonstrates greater robustness across varying grid scales. This study underscores that when constructing proxies for species’ spatial distribution ranges using grid matrices, the OGC method is more susceptible to MAUP effects than the MST distance method, warranting increased caution in studies employing the OGC approach. Full article

Infection with Campylobacter jejuni is the major cause of human gastroenteritis in the United States and Europe, leading to debilitating autoimmune sequelae in many cases. While considerable progress has been made in detailing the infectious cycle of C. jejuni, a full understanding of the molecular mechanisms responsible for virulence remains to be elucidated. Here, we apply a novel approach by modulating protein expression on the pathogen’s ribosomes by inactivating a highly conserved rRNA methyltransferase. Loss of the RsmA methyltransferase results in a more motile strain with greater adhesive and cell-invasive properties. These phenotypical effects correlate with enhanced expression of specific proteins related to flagellar formation and function, together with enzymes involved in cell wall/membrane and amino acid synthesis. Despite the enhancement of certain virulent traits, the null strain grows poorly on minimal media and is rapidly out-competed by the wild-type strain. Complementation with an active copy of the rsmA gene rescues most of the traits changed in the mutant. However, the complemented strain overexpresses rsmA and displays new flaws, including loss of the spiral cell shape, which is distinctive for C. jejuni. Proteins linked with altered virulence and morphology are identified here by mass spectrometry proteomic analyses of the strains. Full article

Coronodon includes species of basal toothed mysticetes that were initially interpreted as engaging in raptorial feeding and dental filtration. Here, the feeding of this extinct genus is revisited based on recently described specimens and species. Associations between tooth position and types of dental wear were tested, and evidence for feeding behaviors was tabulated using scores from 14 craniodental characters, each mapped onto five alternate phylogenetic hypotheses. Individual character states were interpreted as being supportive, neutral, or contradictory evidence to raptorial feeding, suction feeding, baleen filtration, or dental filtration. Wear in Coronodon was found to be significantly more concentrated on mesial teeth, mesial cusps, higher cusps, and upper teeth. Upper teeth also had mesial cusps more worn than distal cusps, inconsistent with predictions of the dental filtration hypothesis. Wear in notches was correlated with wear on neighboring cusps, and side wear was concentrated on occlusal sides, suggesting both were caused by raptorial feeding. These observations raise the possibility that raptorial feeding was the primary, and maybe even the only, mode of feeding for Coronodon. The feeding scores of reconstructed ancestors leading to crown mysticetes typically display a stepwise decrease in raptorial feeding, a stepwise increase in baleen filtration, and, occasionally, an intermediate but weakly supported stage of dental filtration. For most toothed mysticetes, there is little evidence for or against suction feeding. The method we have developed for studying the origin of baleen can be expanded and allows for multiple hypotheses to be tested without undue emphasis on any particular taxon or set of characters. Full article

The Late Cretaceous of Western North America (Laramidia) supported a diverse dinosaur fauna, with duckbilled dinosaurs (Hadrosauridae) being among the most speciose and abundant members of this assemblage. Historically, collecting and preservational biases have meant that dinosaurs from Mexico and the American Southwest are poorly known compared to those of the northern Great Plains. However, evidence increasingly suggests that distinct species and clades inhabited southern Laramidia. Here, a new kritosaurin hadrosaurid, represented by the anterior part of a skull, is reported from the late Campanian of the Cerro del Pueblo Formation, ~72.5 Ma, in Coahuila, Mexico. The Cerro del Pueblo Formation kritosaur was originally considered to represent the same species as a saurolophine from the Olmos Formation of Sabinas, but the Sabinas hadrosaur is now considered a distinct taxon. More recently, the Cerro del Pueblo Formation kritosaur has been referred to Kritosaurus navajovius. We show it represents a new species related to Gryposaurus. The new species is distinguished by its large size, the shape of the premaxillary nasal process, the strongly downturned dentary, and massive denticles on the premaxilla’s palatal surface, supporting recognition of a new taxon, Coahuilasaurus lipani. The dinosaur assemblage of the Cerro del Pueblo Formation shows higher diversity than the contemporaneous fauna of the Horseshoe Canyon Formation in Alberta. Furthermore, Kritosaurini, Lambeosaurini, and Parasaurolophini all persist into the latest Campanian in southern Laramidia after disappearing from northern Laramidia. These patterns suggest declining herbivore diversity seen at high latitudes may be a local, rather than global phenomenon, perhaps driven by cooling at high latitudes in the Late Campanian and Maastrichtian. Full article