Two new species of honeyguides (Indicatoridae) are described from the Lower Pliocene Upper Varswater Formation at Langebaanweg, South Africa. One of these species is referred to the genus Indicator, as Indicator sp. (taxon A), and comparable in size to the Lesser Honeyguide (I. minor). It is represented by a partial coracoid as well as 12 humeri, eight carpometacarpi, and two tarsometatarsi. The second species is slightly smaller than the Least Honeyguide (I. exilis). It is known from a fragmentary proximal humerus, a carpometacarpus and two tarsometatarsi, and cannot be referred to a particular genus of modern Indicatoridae, hence it is referred to Indicatoridae indet. (taxon B). Both species form the as yet earliest record of honeyguides in Africa and the world, and confirm the presence of woodland with mature trees suitable for cavity-nesting species at Langebaanweg during the Early Pliocene.
Priscila S. Rothier, Anthony Herrel, Roger B. J. Benson
et al.
Abstract Body mass plays a fundamental role in the macroevolutionary dynamics of morphological, ecological, and phylogenetic diversification. Given biomechanical principles, large body masses in terrestrial vertebrates may impose important constraints on the adaptative potential of skeletal morphology. This is especially true for the limbs, which are involved in both supporting and propelling the body during locomotion. We present a novel framework for evaluating how body mass structures patterns of morphological, ecological, and phylogenetic diversification using a dataset of forelimb traits for more than 600 terrestrial mammal species. We found that forelimb shape disparity increases with body mass for mammals generally as well as within mammalian subclades, suggesting that this trend is robust to phylogenetic scale. However, both phylogenetic and locomotor diversity (a proxy for ecological diversity) were high for all except the largest mammals and were not strongly associated with body mass. This suggests that small mammals are capable of speciating widely and evolving novel locomotor modes without requiring drastic changes to forelimb shape. However, as body mass increases, biomechanical constraints require substantial morphological changes to the forelimb to adapt to similar levels of locomotor mode disparity. We also show that different limb bone elements do not respond in the same way to increases in body mass when analyzed individually, perhaps due to differing developmental constraints. We provide new insights on how body mass structures macroevolutionary processes in mammals, and our approach can be generalized to examine this question for a variety of traits, ecological modes, and phylogenetic groups.
Aleksander Goll, Lara Dutra, Joanna Nowicka
et al.
Background: Our study explores the role of bats as reservoirs of coronaviruses. Methods: We conducted virological screening of bats hibernating in military bunkers at the Natura 2000 site “Nietoperek” in Western Poland collecting oral and anal swab samples from 138 bats across six species to apply a combination of pan-coronavirus and SARS-CoV-2 specific PCR assays. Results: Only one anal swab tested positive for coronavirus. No SARS-CoV-2 was detected in any of the samples. The low prevalence of coronavirus in the studied colony contrasts with higher rates found in other regions and may be influenced by hibernation. Conclusions: Hibernating bats may show a low prevalence of coronavirus, potentially due to the hibernation process itself. This finding indicates that hibernating bats may not be the most optimal subjects for screening zoonotic pathogens. However, biomonitoring of bats for emerging and reemerging diseases is recommended for comprehensive epidemiological insights.
Charlotte G. Clay, Alexander M. Dunhill, James D. Reimer
et al.
Summary: Extensive global habitat degradation and the climate crisis are tipping the biosphere toward a “sixth” mass extinction and marine communities will not be spared from this catastrophic loss of biodiversity. The resilience of marine communities following large-scale disturbances or extinction events is mediated by the life-history traits of species and their interplay within communities. The presence and abundance of traits in communities provide proxies of function, but whether the breakdown of their associations with species loss can delineate functional loss remains unclear. Here, we propose that relationships between traits within trait networks provide unique perspectives on the importance of specific traits, trait combinations, and their role in supporting the stability of communities, while exploring the vulnerability of both past deep time and present-day marine communities.
A review of the morphological patterns exhibited by all the main radiations of mysticete (baleen whale) cetaceans provided a broad assessment of the fundamental morphological transformations that occurred in the transition to the Mysticeti clade. Skull and postcranial characters were illustrated, described and compared, and their distribution was mapped on a combined phylogeny in the search for morphological support for the principal mysticete clades (i.e., Mysticeti, Chaeomysticeti and Balaenomorpha). In particular, characters of the skull (rostrum, vertex, temporal fossa, tympanic bulla and dentary) and the postcranial appendicular skeleton (scapula, humerus, radius and ulna) were all involved at different degrees in the process of morphological transformations leading to the modern-day mysticetes. Apart from a few typical characteristics of the rostrum that were already present in the earliest-diverging mysticetes (presence of lateral process of the maxilla, presence of multiple dorsal infraorbital foramina, thin lateral border of maxilla and presence of mesorostral groove), most of the other anatomical districts were unaffected by the transition so the earliest mysticetes show a number of archaeocete characters in the tympanic bulla, dentary and skull roof. The analysis of the whole dataset supported the hypothesis that the origin and evolution of mysticetes constituted a step-wise process and that the <i>bauplan</i> of the modern-day mysticetes was fully assembled at the level of the common ancestor of all Balaenomorpha.
SYOUMA HIKMAHTIAR, Mike Kaminski, CLAUDIA G. CETEAN
Deep-water agglutinated foraminifera (DWAF) are investigated from the lower Paleocene of the Contessa Highway Paleocene (CHP) section in the Umbria-Marche Basin in Italy. In the lowermost part of the Paleocene corresponding to the P0–Pα interval and lowermost P1 planktonic foraminifera zones, a total of 46 species of DWAF are identified. A comparison with the uppermost Maastrichtian DWAF assemblages documented by Cetean (2009) results in a combined total of 94 DWAF species over the Cretaceous/Paleogene boundary interval at Contessa Highway. Of these, 49 species are listed as extinction taxa, nine are survivor taxa, 19 are Lazarus taxa, and 17 taxa display first occurrences in the Paleocene. The record of DWAF in the Contessa Highway Paleocene section displays a moderate decrease in diversity across the K/Pg boundary, followed by a gradual recovery in the first meter of the Paleocene. The lower Paleocene record is characterized by blooms of opportunistic species belonging to the genera Reophax, Subreophax, Repmanina, and Spiroplectinella. The K/Pg boundary interval records a major change in the proportions of DWAF morphogroups, from a suspension-feeding community in the Maastrichtian to one dominated by epifaunal detritivores in the lower Paleocene, reflecting a fundamental change in marine primary productivity following the bolide impact.
ZHE-XI LUO , BHART-ANJAN S. BHULLAR, ALFRED W. CROMPTON
et al.
CT visualization of the mandible and dentition of Hadrocodium wui, a stem mammaliaform from the Lower Jurassic
Lower Lufeng Formation of Yunnan, China has revealed new features not accessible by previous microscopic study of
the fossil. Its mandible shows a postdentary trough with an overhanging medial ridge and a short Meckel’s sulcus. An
incomplete part of the ectotympanic and possibly a remnant of Meckel’s element are preserved in the postdentary trough.
Thus, Hadrocodium is similar to other mammaliaforms in retaining a mandibular middle ear, contrary to our earlier interpretation. The mandible exhibits a large postcanine diastema from shedding of anterior premolars without replacement,
an age-dependent feature better developed in older adults. Another adult feature is the alignment of the ultimate molar
to the coronoid process. This is consistent with age-dependent changes in other mammaliaforms where the last molars
of the toothrow shift from medial of the coronoid process in the juvenile, to a position in front of the coronoid process
in the adult. The mandible has a short mobile symphysis. The dentition consists of I5, C1 (two-rooted), P3 (including
P1 position) and M2 (M2 with confluent roots), and i4, c1 (partially two-rooted), p3, and m2 (m2 with partially confluent roots). The two-rooted upper canines are more derived than other Early Jurassic mammaliaforms from the same
fauna, although similar to docodontans. Hadrocodium is unique in that the lower m2 cusp a occludes in the embrasure
between upper M1–M2, but the posterior part of m2 shows between-cusp occlusion with upper M2 main cusp A. M2 is
half the size of the lower m2, and occludes only with the distal half of m2. The upper postcanines show a steep gradient
of posteriorly decreasing tooth size, more so than other mammaliaforms. The CT examination corroborates that there
are no unerupted teeth in the upper or lower jaws, and the holotype of H. wui is dentally and osteologically mature and
capable of independent feeding.
Abstract Findings of ammonoid soft tissues are extremely rare compared to the rich fossil record of ammonoid conchs ranging from the Late Devonian to the Cretaceous/Paleogene boundary. Here, we apply the computed-tomography approach to detect ammonoid soft tissue remains in well-preserved fossils from the Early Cretaceous (early Albian) of NE-Germany of Proleymeriella. The ammonites were found in glauconitic–phosphatic sandstone boulders. Analyses of the high-resolution Ct-data revealed the presence of cameral sheets, the siphuncular tube wall, and the siphuncle itself. The siphuncle is a long, segmented soft tissue that begins at the rear end of the body chamber and comprises blood vessels. Chemical analyses using energy-dispersive spectroscopy (EDS) showed that all preserved soft tissues were phosphatized and are now composed of fluorapatite. The same holds true for preserved shell remains that locally show the nacreous microstructure. We provide a short description of these soft tissue remains and briefly discuss the taphonomic pathway.
David J. Peterman, Kathleen A. Ritterbush, Charles N. Ciampaglio
et al.
Abstract The internal architecture of chambered ammonoid conchs profoundly increased in complexity through geologic time, but the adaptive value of these structures is disputed. Specifically, these cephalopods developed fractal-like folds along the edges of their internal divider walls (septa). Traditionally, functional explanations for septal complexity have largely focused on biomechanical stress resistance. However, the impact of these structures on buoyancy manipulation deserves fresh scrutiny. We propose increased septal complexity conveyed comparable shifts in fluid retention capacity within each chamber. We test this interpretation by measuring the liquid retained by septa, and within entire chambers, in several 3D-printed cephalopod shell archetypes, treated with (and without) biomimetic hydrophilic coatings. Results show that surface tension regulates water retention capacity in the chambers, which positively scales with septal complexity and membrane capillarity, and negatively scales with size. A greater capacity for liquid retention in ammonoids may have improved buoyancy regulation, or compensated for mass changes during life. Increased liquid retention in our experiments demonstrate an increase in areas of greater surface tension potential, supporting improved chamber refilling. These findings support interpretations that ammonoids with complex sutures may have had more active buoyancy regulation compared to other groups of ectocochleate cephalopods. Overall, the relationship between septal complexity and liquid retention capacity through surface tension presents a robust yet simple functional explanation for the mechanisms driving this global biotic pattern.
Gordon M. Shepherd, Timothy B. Rowe, Charles A. Greer
Odor stimuli consist of thousands of possible molecules, each molecule with many different properties, each property a dimension of the stimulus. Processing these high dimensional stimuli would appear to require many stages in the brain to reach odor perception, yet, in mammals, after the sensory receptors this is accomplished through only two regions, the olfactory bulb and olfactory cortex. We take a first step toward a fundamental understanding by identifying the sequence of local operations carried out by microcircuits in the pathway. Parallel research provided strong evidence that processed odor information is spatial representations of odor molecules that constitute odor images in the olfactory bulb and odor objects in olfactory cortex. Paleontology provides a unique advantage with evolutionary insights providing evidence that the basic architecture of the olfactory pathway almost from the start ∼330 million years ago (mya) has included an overwhelming input from olfactory sensory neurons combined with a large olfactory bulb and olfactory cortex to process that input, driven by olfactory receptor gene duplications. We identify a sequence of over 20 microcircuits that are involved, and expand on results of research on several microcircuits that give the best insights thus far into the nature of the high dimensional processing.
Two isolated teeth, a dorsal vertebra, fragments of a humerus and femur, a fragmentary pubic “boot” and part of an ischium shaft, identified here as belonging to a large predatory archosaur were discovered in the Upper Triassic site at Marciszów near Zawiercie (southern Poland). Comparisons of the new fossils from Marciszów with the dorsal vertebrae, pubic “boot”, ischium and femur of the theropod-like Smok wawelski from Lisowice (Silesia) reveal that the two taxa are very similar. Nevertheless, due to the lack of more diagnostic elements (e.g., braincase or cranial elements), we prefer to consider all described specimens from Marciszów as Smok sp. Smok sp. shares a low mound-like, anterior trochanter with trochanteric shelf on the femur, a massive pubic “boot” with a distinct depression (= bevelled area), and a transversely lenticular ischium shaft in cross-section with S. wawelski. Some observed characters of the dorsal vertebra (e.g., lack of some lamina, shape and position of zygapophyses), however, are different from S. wawelski and may also suggest that the new findings represent a second species of the genus in the Upper Triassic of Poland. The discovery of Smok sp. at Marciszów is significant because it is the second example of the co-occurrence of this genus with: (i) bones of a large dicynodont; and (ii) record of gnawed tetrapod bones. The discovery of Smok sp. and the lack of significant morphologic divergence from S. wawelski suggest that this taxon is the only large-bodied predator currently known from the Upper Triassic of Poland. This new evidence expands the record of the genus and contributes, in some measure, to our knowledge of the stratigraphical distribution of large predatory archosaurs from the Polish Upper Triassic bone-bearing levels.
MARIA BIANCA CITA, ELISABETTA PARISI, MARIDA BAXIU
A portion of a deep-sea core that contains a purely pelagic low- sedimentation-rate succession, extends in time from approximately 260,000 to 160,000 y BP, includes the Gephyrocapsa oceanica/Emiliania
huxleyi zonal boundary, and the four sapropels S-9 through S-6, was investigated in detail. Carbonate content, org C content, grain-size analysis, composition of the sand-size sediment fraction, isotopic composition of O and C were measured with an observation point every approximately 300Oy. Cyclicity represented by the sapropels is fairly regular and is of the order of 20,000 y (Milankovitch precession cycles). The grain-size increases consistently in the sapropels, whereas the carbonate content usually decreases, with the exception of S-6. Biogenic components are always dominant, whereas organic matter abounds in sapropels, especially in S-7 which records 9% org C. The number of planktonic foraminifers ranges around a few thousands per gram of sediment; increases of one order of magnitude are noticed in sapropels S-6 and S-8, thus supporting increased productivity, as suggested by the dominance of Neogloboquadrina dutertrei. The consistent decrease in the number of pteropod fragments in all sapropel layers is attributed to dissolution of the easily dissolvable aragonitic tests in the deep-sea acidic environment.
We present revision of the taxonomy and palaeoecology of the Ordovician aristocystitid Lepidocalix pulcher from the Zaouïa of Stita (Great Kabylia, Algeria). An emended diagnosis is proposed, highlighting the four-fold ambulacral system and the typical thecal plating organised in circlets. Lepidocalix is here assigned to the subfamily Calicinae of the family Aristocystitidae. The latex casts show fitted sutures between plates, slightly abraded spines, and well-preserved oral surface. The thecal plates possess up to three dipores, each, included into the spines. The presence of such covered diplopores would have reduced the respiration rate, by restricting their exchange surface area. The spines covering the dipores are not articulated and they could have a protective role. Lepidocalix is interpreted as stationary epifauna, probably using iceberg strategy to be stabilized into the soft substrate.
ADRIANO GUIDO, ADELAIDE MASTANDREA, FABIO DEMASI
et al.
The Devonian Kess-Kess mounds, cropping out in the Hamar Laghdad Ridge (SE Morocco), provide a useful case-study for understanding the relationships between the microbial metabolic activities and micrite precipitation in an extreme environment. Very fine dark and white wrinkled laminae record microbial activity and the geochemistry of the organic matter allows the characterization of the source organisms. The biogeochemical characterization of extracted organic matter was performed through the functional group analyses by FT-IR Spectroscopy. FT-IR parameters indicate a marine origin and low thermal evolution for the organic material. The organic matter is characterized by the presence of stretching ?C=C vibrations attributable to alkene and/or unsaturated carboxylic acids. Preliminary analysis with GC-MS provides evidence for an autochthonous (<C22) organic matter source for the free carboxylic acids. The origin of short-chain fatty acids that have a marked even over odd C number predominance is attributable to bacteria and/or algae and they are similar to those recorded in recent (Black Sea) and ancient (Late Jurassic to Early Cretaceous) methane-seep microbialites. These biogeochemical signatures of microbial carbonate precipitation in an ancient extreme environment may have implications in astrobiological research considering the recent discovery of carbonate deposits on Mars.
A slab from the Late Jurassic (Early Tithonian) lithographic limestone exhibiting skeletal material of an atoposaurid crocodyliform associated with four echinoids from the vicinity of Kelheim (S-Germany) is described. The atoposaurid is represented by a row of dorsal paravertebral osteoderms, caudal osteoderms, a caudal vertebra and haemapophyses, dorsal ribs, and parts of the right fore- and hindlimb. Some of the bones have been prepared out of the slab and most of them are preserved three-dimensionally, which is in contrast to the general much flattened preservation of atoposaurid skeletons. This well preserved specimen allows one of the most detailed descriptions of an atoposaurid limb skeleton so far, yielding in particular well preserved manual elements. By comparison with all other known atoposaurid taxa, the specimen can be determined to belong to the genus Alligatorellus based on an identical morphology of osteoderms. In contrast, a high ontogenetic variety and missing data make comparisons of limb ratios in different atoposaurids virtually useless for taxonomy. Femoral and tibial lengths suggest that this specimen is the largest atoposaurid known from the Solnhofen-Eichstätt region. It is suggested that the crocodyliform carcass has been washed into the lagoon and was subsequently embedded together with the tests of four holectypoid echinoids, which probably populated the lagoon.doi:10.1002/mmng.201100007
DANIELE GIANOLLA, MAURO NEGRI, DANIELA BASSO
et al.
The interdisciplinary study of two deep cores drilled in Pleistocene basin fill at Northern margin of Po Plain, has been integrated with qualitative and quantitative malacological analysis. The potential of quantitative malacological analysis, to refine results obtained from interdisciplinary studies, is here highlighted. The evolution of malacological assemblages has been recorded and correlated to the general regressive trend recognized all over the Po Basin. Lower Pleistocene marine deposits, found at core base (Jaramillo Subchron and older), were gradually replaced by transitional and continental deposits since latest early Pleistocene. Area was eventually covered by continental conglomerate deposits (“Ceppo” facies) during middle-late Pleistocene. Within this general trend, regional significance of a major unconformity (“r” surface), related to onset of Pleistocene glacial cycle, is confirmed. However, as evidenced by malacology, the roughly synchronous onset of coarse clastic progradation did not result in a synchronous shift from marine to transitional and continental settings all over the study area, as an effect of inherited topography and other local factors. During marine sedimentation, fossil record allowed us to recognize a transgressive event, reliably correlated to Marine Isotope Stage 35.