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At least 343 records · Page 19Linked to original sources
USGS2021

Rapid embryonic development supports the early onset of gill functions in two coral reef damselfishes

The gill is one of the most important organs for growth and survival of fishes. Early life stages in coral reef fishes often exhibit extreme physiological and demographic characteristics that are linked to well-established respiratory and ionoregulatory processes. However, gill development and function in coral reef fishes is not well-understood. Therefore, we investigated gill morphology, oxygen uptake, and ionoregulatory systems throughout embryogenesis in two coral reef damselfishes, Acanthochromis polyacanthus and Amphiprion melanopus (Pomacentridae). In both species, we found key gill structures to develop rapidly early in the embryonic phase. Ionoregulatory cells appear on gill filaments 3-4 days post fertilization and increase in density, whilst disappearing or shrinking in cutaneous locations. Primary respiratory tissue (lamellae) appears 5-7 days post fertilization, coinciding with a peak in oxygen uptake rates of the developing embryos. Oxygen uptake was unaffected by phenylhydrazine across all ages (pre-hatch), indicating that haemoglobin is not yet required for oxygen uptake. This suggests that gills have limited contribution to respiratory functions during embryonic development, at least until hatching. Rapid gill development in damselfishes, when compared to most of the previously investigated fishes, may reflect preparations for a high-performance, challenging lifestyle on tropical reefs, but may also make reef fishes more vulnerable to anthropogenic stressors.

Journal of Experimental Biology↗
USGS1976

An evaluation of methods for measuring algal growth

Algal growth was expressed as milligrams dry weight per litre with use of the electronic particle counter for determining cell number and cell volume. A gravimetric constant in milligrams dry weight per cubic micrometre was determined. This constant was applicable throughout the growth curve since there was a linear relationship between total cell weight and total cell volume. Cell volume must be considered in measuring growth because there is a change in average cell volume in addition to an increase in cell numbers throughout the growth curve. Chlorella vulgaris and Selenastrum capricornutum exhibited similar growth curves when growth was expressed as cells per litre or as milligrams dry weight per litre. Chlamydomonas reinhardtii appeared to have a lower algal growth potential when measured in cells per litre but had the same growth potential as C. vulgaris and S. capricornutum when expressed as milligrams dry weight per litre. The growth rate for Scenedesmus quadricauda was less than the other three, regardless of how the results were expressed. The image analysis system was used to count different types of algae in a mixed culture. C. reinhardtii , C. vulgaris , and Anacystis nidulans were not grossly distorted by the sample preparation method and could be distinguished from one another by variations in morphology. The counts could be separated by computing the ratio of area to length for each particle and by allowing the computer to sort and count each of the three types. Typical ratios ranged from 5 to 7 for G. reinhardtii , 2 to 4 C. vulgaris , and 0.2 to 1.3 for A. nidulans . The number of types to be counted in a mixture was limited only by the ability to apply shape factors without having an overlap between each type. Both the image analysis and electronic particle counter produced equal count and size measurements. Fluorescence was a sensitive measure of growth on a laboratory prepared medium since there was a logarithmic relationship between fluorescence and cells per millilitre for both C. vulgaris and S. capricornutum . Fluorescence measurements were not satisfactory for determining growth in samples of varying chemical composition (which occurs in natural samples) because the chlorophyll-to-cell ratio varied with media composition. This was especially pronounced with C. vulgaris .

Journal of Research of the U.S. Geological Survey↗
USGS2017

Evolution, biogeography, and systematics of Puriana: evolution and speciation in Ostracoda, III.

Three types of geographic isolation—land barriers, deep water barriers, and climatic barriers—resulted in three distinct evolutionary responses in Neogene and Quaternary species of the epineritic ostracode genus Puriana . Through systematic, paleobiogeographic, and morphologic study of several hundred fossil and Recent populations from the eastern Pacific, western Atlantic, Gulf of Mexico, and the Caribbean, the phylogeny of the genus and the geography of speciation events were determined. Isolation of large populations by the Isthmus of Panama during the Pliocene did not lead to lineage splitting in species known to have existed before the Isthmus formed. Conversely, the establishment of small isolated populations on Caribbean islands by passive dispersal mechanisms frequently led to the evolution of new species or subspecies. Climatic changes along the southeastern United States during the Pliocene also catalyzed possible parapatric speciation as populations that immigrated to the northeastern periphery of the genus' range split to form new species. The results provide evidence that evolutionary models describing the influence of abiotic events on patterns of evolution and speciation can be tested using properly selected tectonic and climatic events and fossil groups amenable to species-level analysis. Two new species, P. bajaensis and P. paikensis , are described.

Journal of Paleontology↗
USGS2010

Crater population and resurfacing of the Martian north polar layered deposits

Present‐day accumulation in the north polar layered deposits (NPLD) is thought to occur via deposition on the north polar residual cap. Understanding current mass balance in relation to current climate would provide insight into the climatic record of the NPLD. To constrain processes and rates of NPLD resurfacing, a search for craters was conducted using images from the Mars Reconnaissance Orbiter Context Camera. One hundred thirty craters have been identified on the NPLD, 95 of which are located within a region defined to represent recent accumulation. High Resolution Imaging Science Experiment images of craters in this region reveal a morphological sequence of crater degradation that provides a qualitative understanding of processes involved in crater removal. A classification system for these craters was developed based on the amount of apparent degradation and infilling and where possible depth/diameter ratios were determined. The temporal and spatial distribution of crater degradation is interpreted to be close to uniform. Through comparison of the size‐frequency distribution of these craters with the expected production function, the craters are interpreted to be an equilibrium population with a crater of diameter D meters having a lifetime of ∼30.75 D 1.14 years. Accumulation rates within these craters are estimated at 7.2 D −0.14 mm/yr, which corresponds to values of ∼3–4 mm/yr and are much higher than rates thought to apply to the surrounding flat terrain. The current crater population is estimated to have accumulated in the last ∼20 kyr or less.

Journal of Geophysical Research E: Planets↗
USGS2004

Imaging fall Chinook salmon redds in the Columbia River with a dual-frequency identification sonar

We tested the efficacy of a dual-frequency identification sonar (DIDSON) for imaging and enumeration of fall Chinook salmon Oncorhynchus tshawytscha redds in a spawning area below Bonneville Dam on the Columbia River. The DIDSON uses sound to form near-video-quality images and has the advantages of imaging in zero-visibility water and possessing a greater detection range and field of view than underwater video cameras. We suspected that the large size and distinct morphology of a fall Chinook salmon redd would facilitate acoustic imaging if the DIDSON was towed near the river bottom so as to cast an acoustic shadow from the tailspill over the redd pocket. We tested this idea by observing 22 different redds with an underwater video camera, spatially referencing their locations, and then navigating to them while imaging them with the DIDSON. All 22 redds were successfully imaged with the DIDSON. We subsequently conducted redd searches along transects to compare the number of redds imaged by the DIDSON with the number observed using an underwater video camera. We counted 117 redds with the DIDSON and 81 redds with the underwater video camera. Only one of the redds observed with the underwater video camera was not also documented by the DIDSON. In spite of the DIDSON's high cost, it may serve as a useful tool for enumerating fall Chinook salmon redds in conditions that are not conducive to underwater videography.

North American Journal of Fisheries Management↗
USGS2010

Interpretation and analysis of planetary structures

Structural geology is an integral part of planetary science. Planetary structures provide the framework for determining the character and sequence of crustal deformation while simultaneously establishing the observational basis required to test geodynamic hypotheses for the deformation of planetary and satellite lithospheres. The availability of datasets that record spatial and topographic information with a resolution that matches or, in many cases, exceeds, what is available for Earth-based studies permits the deformation of several planets and satellites to be investigated down to the local or outcrop scales. The geometry and kinematics of common planetary structures such as joints, igneous dikes, deformation bands, faults, and folds can be determined with confidence from their distinctive morphologic and topographic signatures, enabling the structural histories and deformation magnitudes to be determined. Segmentation, displacement profiles, relay ramps, footwall anticlines, displacement-controlled depocenters, and other well-known characteristics of terrestrial normal fault and graben systems reveal the sequence and processes of fault growth in numerous planetary examples. Systems of thrust faults having both blind and surface-breaking components are important elements on several bodies including Mercury, the Moon, and Mars. Strike-slip faults have been identified on bodies including Mars and Europa with oblique extension found on Ganymede. Using field-based studies of Earth-based structures as a guide, planetary structures provide a means to explore and evaluate the causative stresses. Despite the wide range in structural styles across the solar system, plate tectonics is recognized only on the Earth, with the other planets and satellites deforming in the absence of large-scale horizontal motions and attendant plate recycling.

Journal of Structural Geology↗
USGS2015

Enigmatic eight-meter trace fossils in the Lower Pennsylvanian Lee sandstone, central Appalachian basin, Tennessee

Enigmatic tubular trace fossils up to eight meters long occur in the Lower Pennsylvanian Middlesboro Member of the Lee Formation. Two morphotypes occur: type 1 trace fossils are plain, smooth, vertical, nonbranching, parallel-walled, tubular structures; type 2 trace fossils branch, have walls with faint vertical striations, regularly or irregularly spaced nodes, and funnel-shaped terminations. Sandstone casts filling type 2 structures have helical spiral morphology, and, in rare individuals, faint meniscate fills have been observed. Both trace-fossil morphotypes have poorly cemented wall linings containing framboidal pyrite, amorphous carbon, quartz sand, and poorly preserved fecal material. The trace fossils occur in a massive, structureless, channel-form sandstone, originating at the contact between a channel lag and the overlying massive fill. The stratigraphic sequence is interpreted to represent a barrier island transgressing an estuarine facies. A tidal inlet within the barrier facies scoured into the underlying estuarine sediments. Subsequent rapid filling of the inlet led to the deposition of the massive sandstone. Origin of these structures is uncertain. The preponderance of evidence favors the hypothesis that the structures are escape burrows of animals that had colonized, or were concentrated in, the lag and were suddenly buried by the deposition of the massive sand. However, no likely burrower has been identified, and several characteristics of the structures and the enclosing sediments indicate that they may be completely inorganic in origin.

Journal of Paleontology↗
USGS1999

Does Europa have a subsurface ocean? Evaluation of the geological evidence

It has been proposed that Jupiter's satellite Europa currently possesses a global subsurface ocean of liquid water. Galileo gravity data verify that the satellite is differentiated into an outer H 2 O layer about 100 km thick but cannot determine the current physical state of this layer (liquid or solid). Here we summarize the geological evidence regarding an extant subsurface ocean, concentrating on Galileo imaging data. We describe and assess nine pertinent lines of geological evidence: impact morphologies, lenticulae, cryovolcanic features, pull‐apart bands, chaos, ridges, surface frosts, topography, and global tectonics. An internal ocean would be a simple and comprehensive explanation for a broad range of observations; however, we cannot rule out the possibility that all of the surface morphologies could be due to processes in warm, soft ice with only localized or partial melting. Two different models of impact flux imply very different surface ages for Europa; the model favored here indicates an average age of ∼50 Myr. Searches for evidence of current geological activity on Europa, such as plumes or surface changes, have yielded negative results to date. The current existence of a global subsurface ocean, while attractive in explaining the observations, remains inconclusive. Future geophysical measurements are essential to determine conclusively whether or not there is a liquid water ocean within Europa today.

Journal of Geophysical Research: Planets↗
USGS2025

Component identification of solid biomass fuels using reflected light microscopy: Interlaboratory study 2

As nations transition toward sustainable energy systems , biomass has become a vital component of global energy portfolios. Derived from organic materials such as wood, agricultural residues, forestry byproducts, and organic waste, biomass is a renewable energy source with significant environmental and economic benefits. Responsible biomass energy production can improve waste management, reduce emissions of greenhouse gases, and mitigate environmental pollution. However, as the diversity of biomass-derived fuels increases, robust quality assessment methods are essential to ensure their efficiency, safety, and minimal environmental impact. Reflected light microscopy (RLM) is one such technique with the potential to complement conventional physico-chemical analyses by enabling a rapid identification of material constituents and impurities. To refine this methodology and evaluate the reproducibility of solid biomass component identification using RLM, an interlaboratory study (ILS) was conducted. The study involved the recognition of 58 components across 45 photomicrographs, with the participation of 65 scientists and students from 25 countries. The participants faced high difficulty identifying some of the marked components, and as a result, the percentage of correct answers ranged from 19.0 % to 98.3 %, with an average correct identification rate of 62.7 %. The most challenging aspects of the identification process included distinguishing between woody and non-woody (agro) biomass, accurately identifying petroleum-derived materials, and differentiating agro biomass from inorganic matter. The results suggest that while RLM is an important tool for characterizing solid biomass, further development of methodology guidelines and training are necessary to enhance its effectiveness. Future research should prioritize preparing detailed, image-rich, microscopic morphological descriptions of biomass fuel components, which could improve the accuracy and reliability of using RLM in biomass fuel characterization.

International Journal of Coal Geology↗
USGS2025

Does the Lost Jim lava flow (Alaska) really preserve evidence of interaction with permafrost?

The basaltic Lost Jim lava flow, the youngest member of the Imuruk Lake volcanic field, Alaska, is reported to have interacted with underlying permafrost by thawing it and forming cavities into which the lava flow collapsed, forming pits and other depressions on the lava flow's surface. Our field observations contradict this hypothesis. The Lost Jim lava flow exhibits surface features typical of an inflated pāhoehoe flow, and we propose instead that most of the pits are unambiguously the result of flow inflation (i.e., lava-rise pits). These pits are found on elevated, relatively level surfaces, and their inner walls preserve features like rotated surface slabs and fine-scale flow banding on exposed crack surfaces, both of which are hallmarks of lava flow inflation. While collapse pits do exist on the Lost Jim lava flow, they are morphologically distinct and formed by crustal failure into drained lava tubes. Satellite images of the Lost Jim lava flow show similarities in the size and distribution of pits within other young pāhoehoe lava flows scattered across the globe. The small diameter of many of the pits (<10 m), compared to flow thickness (≥10 m), also argues against collapse—numerical modeling shows that the relatively high tensile strength of a coherent lava flow would have prevented its collapse into cavities similar in diameter to the lava flow's thickness. Finally, the pits are found scattered across the Lost Jim lava flow, including in locations where the lava flow rests directly on bedrock, which consists of older lava flows. Segregated ice lenses and soil expansion—necessary components for thermokarst formation when thawed—do not exist in such locations. Altogether, these factors show that the Lost Jim lava flow is an inflated lava flow, and permafrost played no significant role during or after its emplacement.

Alaska↗
USGS2006

Electrocardiography in two subspecies of manatee (Trichechus manatus latirostris and Trichechus manatus manatus)

Electrocardiographic (ECG) measurements were recorded in two subspecies of awake, apparently healthy, wild manatees (Trichechus manatus latirostris and T. m. manatus) undergoing routine field examinations in Florida and Belize. Six unsedated juveniles (dependent and independent calves) and 6 adults were restrained in ventral recumbency for ECG measurements. Six lead ECGs were recorded for all manatees and the following parameters were determined: heart rate and rhythm; P, QRS, and T wave morphology, amplitude, and duration; and mean electrical axis (MEA). Statistical differences using a t-test for equality of means were determined. No statistical difference was seen based on sex or subspecies of manatees in the above measured criteria. Statistical differences existed in heart rate (P = 0.047), P wave duration (P = 0.019), PR interval (P = 0.025), and MEA (P = 0.021) between adult manatees and calves. Our findings revealed normal sinus rhythms, no detectable arrhythmias, prolonged PR and QT intervals, prolonged P wave duration, and small R wave amplitude as compared with cetacea and other marine mammals. This paper documents the techniques for and baseline recordings of ECGs in juvenile and adult free-living manatees. It also demonstrates that continual assessment of cardiac electrical activity in the awake manatee can be completed and can be used to aid veterinarians and biologists in routine health assessment, during procedures, and in detecting the presence of cardiac disease or dysfunction.

Journal of Zoo and Wildlife Medicine↗
USGS2015

Coevolution of bed surface patchiness and channel morphology: 1. Mechanisms of forced patch formation

Riverbeds frequently display a spatial structure where the sediment mixture composing the channel bed has been sorted into discrete patches of similar grain size. Even though patches are a fundamental feature in gravel bed rivers, we have little understanding of how patches form, evolve, and interact. Here we present a two-dimensional morphodynamic model that is used to examine in greater detail the mechanisms responsible for the development of forced bed surface patches and the coevolution of bed morphology and bed surface patchiness. The model computes the depth-averaged channel hydrodynamics, mixed-grain-size sediment transport, and bed evolution by coupling the river morphodynamic model Flow and Sediment Transport with Morphological Evolution of Channels (FaSTMECH) with a transport relation for gravel mixtures and the mixed-grain-size Exner equation using the active layer assumption. To test the model, we use it to simulate a flume experiment in which the bed developed a sequence of alternate bars and temporally and spatially persistent forced patches with a general pattern of coarse bar tops and fine pools. Cross-stream sediment flux causes sediment to be exported off of bars and imported into pools at a rate that balances downstream gradients in the streamwise sediment transport rate, allowing quasi-steady bar-pool topography to persist. The relative importance of lateral gravitational forces on the cross-stream component of sediment transport is a primary control on the amplitude of the bars. Because boundary shear stress declines as flow shoals over the bars, the lateral sediment transport is increasingly size selective and leads to the development of coarse bar tops and fine pools.

Journal of Geophysical Research F: Earth Surface↗
USGS2023

Viscous relaxation of Oort and Edgeworth craters on Pluto: Possible indicators of an epoch of early high heat flow

Impact craters, with their well-defined initial shapes, have proven useful as heat flow probes of a number of icy bodies, provided characteristics of viscous relaxation can be identified. For Pluto's numerous craters, such identifications are hampered/complicated by infilling and erosion by mobile volatile ices, but not in every case. Large craters offer relatively deep probes of rheological structure, and on Pluto two large old craters in a major dark (volatile-ice free) region are probably the best examples for possible viscous relaxation: Oort (115-km diameter) and Edgeworth (140-km diameter). They are similar in size, location, and apparent age (morphological preservation), but may or may not be coeval. Edgeworth is particularly shallow and its floor appears bowed up above the original ground plane, a classic hallmark of viscous relaxation in which viscosity decreases sharply with depth. Oort is less relaxed, but may be somewhat younger and less affected by an early epoch of high heat flow. Finite element calculations show that this heat flow would have to have been substantial to explain Edgeworth's upbowed floor by viscous relaxation, several times steady-state radiogenic values for present-day surface temperatures. We expect Pluto's brittle ice lithosphere to be fractured and porous, however, markedly reducing thermal conductivity and increasing temperatures at depth and relaxation for a given heat flow. We find that most relaxation occurs well within 100 Myr after impact for Edgeworth and Oort, and focus attention on a temporal (and/or regional) epoch of elevated heat flow, possibly tied to the serpentinization of Pluto's rocky core.

Journal of Geophysical Research: Planets↗
USGS2024

Measuring erosional and depositional patterns across Comet 67P's imhotep region

Comet 67P/Churyumov-Gerasimenko displays a pronounced hemispherical dichotomy in surface morphology, where the southern hemisphere exhibits more erosional features than the northern hemisphere due to receiving much greater solar radiation. Consequently, it is generally assumed that particles are ejected from the southern hemisphere through sublimation and a significant fraction eventually descends as airfall, covering the northern terrains. To investigate this south-to-north material transfer during the comet's perihelion passage, we used photoclinometry to measure material redistribution within its most extensive smooth terrain deposit around the Imhotep region. However, our findings do not align with this expected trend. Instead, we show that local-scale processes substantially impact the erosion and accumulation of material, with one area experiencing net erosion while another nearby region, just a few dozen meters away, sees sediment buildup. Our analysis underscores the complex interplay of processes shaping Comet 67P's surface and likely comets more generally.

Journal of Geophysical Research↗
USGS1998

The ichnogenus Curvolithus revisited

The ichnogenus Curvolithus Fritsch, 1908, originally described from the Ordovician of the Prague Basin, typically comprises ribbonlike or tonguelike, flattened, endostratal traces with three rounded lobes on the upper surface. However, considerable confusion persists regarding the ichnotaxonomic status and diagnostic features of its ichnospecies. The type specimens of this ichnotaxon, overlooked in most subsequent reports, are redescribed herein. Curvolithus multiplex Fritsch, 1908, the type species, is retained for specimens with a trilobate upper surface and a quadralobate lower surface, in contrast to the criteria adopted by subsequent authors. The other ichnospecies originally proposed from the type locality, C. gregarius Fritsch, 1908, actually consists of a series of grouped parallel scratch marks forming ridges and should be removed from Curvolithus. Subsequently, four ichnospecies were defined: C.? davidis Webby 1970; C. annulatus Badve and Ghare 1978; C. aequus Walter et al. 1989; and C. manitouensis Maples and Suttner 1990. Curvolithus? davidis shows the typical trilobation of Curvolithus apparently in its lower surface, but the morphology of the upper surface is uncertain. Accordingly, it does not warrant ichnospecific assessment, and is regarded as a nomen dubium. The nature of the annulations on the trilobate upper surface of C. annulatus is unclear, and this ichnospecies is also best considered as a nomen dubium. Curvolithus aequus has a bilobate lower surface and probably represents washed out specimens of Didymaulichnus. Finally, C. manitouensis comprises specimens with a smooth, trilobate upper surface and a smooth, quadralobate lower surface, and is best regarded as a junior synonym of C. multiplex. Curvolithus multiplex has been used incorrectly for Curvolithus with a trilobate upper surface and a trilobate to unilobate lower surface. The new ichnospecies, Curvolithus simplex, is proposed herein for such traces. Curvolithus is interpreted as a locomotion trace (Repichnia) of endostratal carnivores, possibly gastropods, flatworms, or nemerteans. Curvolithus is a component of the Cruziana ichnofacies in shallow-marine facies, either of normal salinity or slightly brackish, in the latter case typically associated with fan deltas.

Journal of Paleontology↗
USGS2005

Stock structure of Lake Baikal omul as determined by whole-body morphology

In Lake Baikal, three morphotypes of omul Coregonus autumnalis migratorius are recognized; the littoral, pelagic, and deep-water forms. Morphotype assignment is difficult, and similar to that encountered in pelagic and deep-water coregonines in the Laurentian Great Lakes. Principal component analysis revealed separation of all three morphotypes based on caudal peduncle length and depth, length and depth of the body between the dorsal and anal fin, and distance between the pectoral and the pelvic fins. Strong negative loadings were associated with head measurements. Omul of the same morphotype captured at different locations were classified to location of capture using step-wise discriminant function analysis. Jackknife correct classifications ranged from 43 to 78% for littoral omul from five locations, and 45&ndash;86% for pelagic omul from four locations. Patterns of location misclassification of littoral omul suggested that the sub-population structure, hence stock affinity, may be influenced by movements and intermixing of individuals among areas that are joined bathymetrically. Pelagic omul were more distinguishable by site and may support a previous hypothesis of a spawning-based rather than a foraging-based sub-population structure. Omul morphotypes may reflect adaptations to both ecological and local environmental conditions, and may have a genetic basis.

Journal of Fish Biology↗
USGS2023

Validating morphometrics as a nonlethal tool to determine Arctic Grayling sex

Objective Some graylings Thymallus spp. possess an elongated dorsal fin and other morphological traits that can be sexually dimorphic, as demonstrated in the European Grayling T. thymallu s. North American Arctic Grayling T. arcticus are assumed to follow these trends, but decisive evidence is lacking. This study aimed to determine whether sexually dimorphic characteristics, including posterior dorsal height, can be used to accurately predict the sex of Arctic Grayling in Interior Alaska. Methods We used computer imaging software to measure 22 morphometrics on 97 Arctic Grayling of known sex from streams in Interior Alaska, and we developed a set of binomial models to evaluate the validity of morphometrics as predictors of Arctic Grayling sex. Result Posterior dorsal height was a reasonably accurate predictor of sex (~90% accurate at fork lengths ≥300 mm), although models containing additional morphometrics were more accurate (100% accuracy at fork lengths ≥250 mm). Conclusion This study presents an affordable, noninvasive, and replicable method for nonlethal determination of Arctic Grayling sex by using digital images from the field, with potential application to other salmonids.

North American Journal of Fisheries Management↗
USGS2019

See how they ran: Morphological and functional aspects of skeletons from ancient Egyptian shrew mummies (Eulipotyphla: Soricidae: Crocidurinae)

Animals served important roles in the religious cults that proliferated during the Late (ca. 747–332 BCE) and Greco-Roman periods (332 BCE–CE 337) of ancient Egypt. One result was the interment of animal mummies in specialized necropolises distributed throughout the country. Excavation of a rock-tomb that was re-used during the Ptolemaic Period (ca. 309–30 BCE) for the interment of animal mummies at the Djehuty Site (TT 11-12) near Luxor, Egypt, was carried out in early 2018 by a Spanish-Egyptian team sponsored by the Consejo Superior de Investigaciones Científicas, Madrid. The tomb burned sometime after deposition of the mummies, leaving behind abundant disassociated skeletal remains, primarily of avians, but also including two species of shrews (Soricidae): Crocidura olivieri (Lesson, 1827) and C. religiosa (I. Geoffroy Saint-Hilaire, 1826). To investigate possible intraspecific variation in morphology and locomotor function in these two species during the last two millennia, we measured morphological features of individual postcranial bones from the two archaeological samples and calculated indices that have been used to assess locomotor function. We compared the measurements to those from modern C. olivieri , C. religiosa , and C. suaveolens (Pallas, 1811) using principal components analysis, and we compared locomotor indices to those we calculated for the three modern species of Crocidura and to those from nine species of myosoricine shrews. Osteological features of the postcranial skeleton of conspecific Ptolemaic and modern samples of C. olivieri and C. religiosa are generally similar in character and proportion, and, skeletally, these shrews and modern C. suaveolens are consistent with soricids having a primarily ambulatory locomotor mode. One exception is the deltopectoral crest of the humerus, which appears to be longer in modern C. religiosa. Despite general conservation of form and function, Ptolemaic C. olivieri had larger body size than modern Egyptian populations and were more similar in size to modern C. olivieri nyansae , 1900 from Kenya than to modern C. olivieri olivieri from Egypt.

Luxor↗