Ephemeral Bodies Research Articles

Transcriptomic data support phylogenetic congruence and reveal genomic changes associated with the repeated evolution of annualism in aplocheiloid killifishes (Cyprinodontiformes)

Repeated evolution of novel life histories that are correlated with ecological variables offers opportunities to study convergence in genetic, developmental, and metabolic features. Nearly half of the 800 species of Aplocheiloid killifishes, a clade of teleost fishes with a circumtropical distribution, are “annual” or seasonal species that survive in ephemeral bodies of water that desiccate and are unfeasible for growth, reproduction, or survival for weeks to months every year. But the repeated evolution of adaptations that are key features of the annual life history among these fishes remains poorly known without a robust phylogenetic framework. We present a large-scale phylogenomic reconstruction of aplocheiloid killifishes evolution using newly sequenced transcriptomes obtained from a diversity of killifish lineages representing putative independent origins of annualism. Ancestral state estimation shows that developmental dormancy (diapause), a key trait of the killifish annual life cycle, may have originated up to seven times independently among African and South American lineages. To further explore the genetic basis of this unique trait, we measure changes in evolutionary rates among orthologous genes across the killifish tree of life by quantifying codon evolution using dN/dS ratios. We show that some genes have higher dN/dS ratios in lineages leading to species with annual life history. Many of them constitute key developmental genes or nuclear-encoded metabolic genes that control oxidative phosphorylation. Lastly, we compare these genes with higher ω to genes previously associated to developmental dormancy and metabolic shifts in killifishes and other vertebrates, and thereby identify molecular evolutionary signatures of repeated transitions to extreme environments.

A unique notostracan trace fossil assemblage from the Upper Triassic Chinle Formation (northeastern Utah, USA) and its paleoecological and paleoenvironmental implications

The Upper Triassic (Norian) Chinle Formation of the southwest USA is world-renowned for its diverse fossil assemblages. Here we describe a new trace fossil assemblage from the formation in Dinosaur National Monument (northeastern Utah), and discuss its paleoenvironmental implications. The trace fossils comprise freshwater bilobate resting and feeding traces (Isopodichnus-Rusophycus-morphotype and Isopodichnus-Cruziana-morphotype respectively) as well as walking traces (Acripes), probably of notostracan crustaceans, in a previously unknown subparallel alignment. Extant notostracans are known to live in ephemeral bodies of freshwater with a low water level and temporary desiccation. However, associated sedimentological features such as prod marks and groove casts indicate that the traces were produced under the influence of a low velocity, unidirectional current which is typical for sheet-flows – an interpretation independently corroborated by further sedimentological data. Thus, the trace fossil assemblage supports the presence of rheotaxis in notostracans, a thus far little-known behavior in these animals. Based on the inferred ecology of the trace maker, the sedimentological features associated with the traces, and the sedimentology of the surrounding rocks, the traces were most likely formed in an ephemeral part of a fluvial system dominated by sheet-flow events. This interpretation supports the results of previous studies suggesting that the upper Chinle Formation at Dinosaur National Monument area is characterized by ephemeral low flow regime sheet-flows deposited on mudflats.

Martian fan deposits: Insights on depositional processes and origin from mass balance survey

Fan deposits located at the mouths of Martian valleys have been interpreted as indicators of wet conditions during Mars history. However, the processes, time and amount of water needed to carve the valleys and form the fans are still debated. Here we present a detailed morphometric and mass balance analysis of valleys and fan-shaped deposits using high resolution topography, which provides new insights into past depositional environments.Based on morphometric and volumetric measurements, we found that several Martian fans previously interpreted as deltas can be categorized into two main types. Type I fans are more numerous, relatively well preserved, are associated with smaller and less mature drainage networks and were deposited on steeper gradients. The balance between eroded and deposited materials indicates that this set of fans might have been formed mainly in subaerial settings by depositional processes other than typical deltaic sedimentation (e.g. alluvial, glacial, mass-wasting in general), since a significant loss of sediment during deposition did not occur (we obtained a volume ratio of eroded vs. deposited materials of approximately 1). Therefore, we propose that the identified Type I fans were not deposited in prevailing subaqueous deltaic settings, but mainly in subaerial conditions with perhaps sporadic presence of ephemeral bodies of standing water within the basins.In contrast, Type II fans are less abundant, highly eroded, were deposited on flatter areas and formed downstream of more mature drainage networks with longer, deeper and wider valleys. The mass balance for this set of fans clearly shows that considerable amounts of sediment were not retained in the fans, implying large offshore transport of sediment during their formation (eroded vs. deposited volume ratios between 3 and 10 are probable). This evidence supports a fluvio-deltaic origin for this class of fans, indicating the existence of paleolakes over substantial periods of time.Based on the collected morphometric measurements and mass balance modeling we conclude that only a small percentage of the fans (Type II fans correspond to ∼1/3 of the sampled areas) are consistent with the occurrence of favorable and durable conditions for life, i.e. long-lived integrated fluvial, deltaic and lacustrine environments. Whereas, the majority of fans might have been formed in subaerial settings with significant contributions of alternative processes besides fluvial transport and deposition thus not necessarily requiring the occurrence of extended epochs of clement climatic conditions.

Coexisting Discrete Bodies of Rhyolite and Punctuated Volcanism Characterize Yellowstone's Post‐Lava Creek Tuff Caldera Evolution

AbstractIon‐microprobe 206Pb/238U geochronology and trace element geochemistry of the unpolished rims and sectioned interiors of zircons from Yellowstone caldera's oldest post‐caldera lavas provide insight into the magmatic system during the prelude and aftermath of the caldera‐forming Lava Creek supereruption. The post‐caldera lavas compose the Upper Basin Member of the Plateau Rhyolite and fall into two groups based on zircon crystallization age: early lavas with zircon ages between ~750 and 550 ka and late lavas with zircon ages between ~350 and 250 ka. Zircons from the early‐erupted East Biscuit Basin flow yield U‐Pb dates and trace element compositions, which when considered with the Pb isotopic compositions of their coexisting feldspars and pyroxenes, point to an isotopically distinct parental melt present during crystallization of the Lava Creek magma but untapped by the supereruption. Distinct zircon crystallization ages and Pb‐isotope compositions of major minerals between the early and late Upper Basin Member groups suggest contrasting sources in the magma reservoir. As proxies for melt evolution, the zircons indicate that Yellowstone's post‐caldera rhyolites became more evolved between mid‐ to late‐Pleistocene time, during the same interval that melting of hydrothermally altered wall rock and recharge by new silicic magmas changed in their relative roles. The results from this study indicate that discrete and ephemeral bodies of silicic magma, at times within a mush dominated reservoir and including during the prelude to the Lava Creek eruption, have characterized Yellowstone's subvolcanic reservoir.

Mixed fibres: Human and non-human collaboration

Abstract Ephemeral and durable; humble and ubiquitous – paper is a complex material of unique necessity in human lives, treading a line between climatological pariah and saviour. It degrades, rots and burns but can outlast our ephemeral bodies, spending its days withdrawing beneath our activities. This article considers a performance practice with paper in response to the new materialist theories of Karen Barad, as more than the continued instrumentalization of a pervasive yet passive material, but an artistic collaboration. This acknowledges the more-than-human relations we are part of and how we must find ways to work together in consideration of feminist and eco-critical concerns.

Hit pause: Developmental arrest in annual killifishes and their close relatives.

Killifishes survive and persist in extreme environments by exploiting both aquatic and terrestrial habitats for egg deposition, and by adjusting the length of development to match availability of water to support larval growth and maturation. Annual killifishes persist in ephemeral bodies of water through the production of drought-tolerant embryos. Survival of the environmental stresses associated with their highly variable and seasonal habitat is supported by their ability to enter into at least two states of metabolic and developmental dormancy, diapause or quiescence. There are three stages of diapause in annual killifishes, one occurring prior to gastrulation, one about midway through development, and one in late pre-hatching embryos. Quiescence may occur at any developmental stage. In addition, delayed hatching is known to occur in close relatives of the annual killifishes, and may be superficially confused with pre-hatching diapause. These types of developmental delay are induced by different cues and serve different purposes in the life history of the species. Thus, it is likely that the molecular mechanisms that induce dormancy and support survival are unique in each case. It is imperative that we properly define these forms of developmental dormancy in our studies in order to put our results into the proper ecological and evolutionary context. Here the unique characteristics of these distinct categories of developmental delay are reviewed. Developmental Dynamics 246:858-866, 2017. © 2017 The Authors Developmental Dynamics published by Wiley Periodicals, Inc. on behalf of American Association of Anatomists.

The Maastrichtian–Danian Maimará tracksite (Yacoraite Formation, Salta Group), Quebrada de Humahuaca, Argentina: environments and ichnofacies implications

The shoreline carbonate lagoon deposits of the Yacoraite Formation in the Maimará locality, Quebrada de Humahuaca (Jujuy, northwestern Argentina) reveal invertebrate and vertebrate trace fossils that are distributed in two distinct subenvironments: (A) the subtidal-lower intertidal zone (S-LI), a moderate/high energy shoreline under wave and tide action, and (B) the playa-lake zone (PL), a protected supratidal/eulittoral zone that characterizes low energy ephemeral bodies of water. In the S-LI zone there are three suites: I, composed of Skolithos linearis and dinosaur tracks (Hadrosauropodus isp., titanosaurian, ornithischian and theropod tracks); II, composed of monoichnospecific tiers with cf. Taenidium isp.; and III, constituted by abundant didactyl tracks maybe belonging to swimming tracemakers. The trace fossils of the PL zone are included in two suites: I, composed of Lockeia siliquaria and ?Ptychoplasma isp., and II, composed of Palaeophycus tubularis and Planolites cf. montanus with avian tracks (cf. Alaripeda isp.; Avipeda isp., cf. Gruipeda isp., cf. Yacoraitichnus avis) and indeterminate biped dinosaur tracks. The invertebrate trace fossils in both zones (S-LI and PL) display low ichnodiversity and are restricted to the shallow tier with substrate penetration of a few centimeters, which is characteristic of an unfavorable environment for the establishment of a permanent benthic community. Dinosaur tracks were preserved in an “optimal preservation area”, located in between both zones. The trace fossils of the S-LI zone are ascribed in general sense to the Scoyenia and Skolithos Ichnofacies. Following the current knowledge, the trace fossils of the PL zone are assigned to the shorebird ichnosubfacies, within the Scoyenia Ichnofacies.

The revival and decline of rank and file movements in Britain during the 1930s

The economic and political crisis of 1931 provoked the reappearance of rank and file movements in Britain. This article examines the unofficial organisations that developed in building, engineering, passenger transport and the railways – as well as more ephemeral bodies. It critically synthesises the existing historiography and replenishes it with new material from the Russian archives. The progress of rank and filism to 1939 is surveyed and the largely forgotten project of a new Communist-led rank and file organisation, a Trade Union Militant League, which would supersede the National Minority Movement, is recuperated. The article stresses the role of Comintern policy in harnessing and moulding grass-roots rebellion. It validates that strand in the literature which argues that Moscow’s subsequent turn to the popular front and aspirations to alliances with labour movement leaders predominated over, and legitimated, indigenous influences, enhanced existing adaptation to trade unionism, and encouraged subordination of oppositional movements to activity in official structures. By 1939, the Communists had abandoned the idea of a national rank and file movement they had pursued since 1923. Little survived of the revolutionary enterprise launched in 1931. Rank and filism endured only as a handful of sectional, party-sponsored, trade union ginger groups.

Characterization and Classification of Vernal Pool Vegetation, Soil, and Amphibians of Pictured Rocks National Lakeshore

Abstract Vernal pools are isolated ephemeral bodies of water that are often overlooked on the landscape. Despite their temporary nature, these pools are important to forest communities, providing critical breeding habitat for amphibians and an important food and water source for other taxonomic groups including birds, bats, and other terrestrial vertebrates. Sparse information about vernal pools in the upper Midwest, including Pictured Rocks National Lakeshore (PIRO), inhibits conservation. We sampled soil, vegetation, and amphibians in 21 vernal pools in PIRO during spring 2010 to provide quantitative and qualitative evaluation of vernal pool abiotic and biotic characteristics within PIRO to help managers determine which pools to prioritize for conservation. Average vernal pool size sampled was 0.124 ha. Soils had an average of 13.5% carbon and 0.7% nitrogen. Vegetation was diverse within the vernal pools, with 115 vascular plants identified. Five species of amphibians were encountered during our surveys...

Pliocene aridity and Neogene landscape evolution recorded by a fluvial sediment system (Campaspe Formation) in northeast Queensland

Campaspe Formation, a surficial, fluviatile, sand-dominated unit, is extensively developed in the Charters Towers region of north Queensland where it covers an area of 11 000 km2, overlying Paleozoic basement and erosional remnants of Paleogene Southern Cross Formation. In the northern part of its distribution, it is interlayered with, and overlain by, flows of Nulla Basalt. It is dated as mid-Pliocene, based on the 3.48 Ma age of the Myrrilumbing Flow interlayered with its upper part, an antiquity consistent with thin ferricrete locally developed at its surface. The formation defines the Campaspe Surface at an elevation of 200–440 m in the present landscape, falling gently from upland to the west towards the current channel of the Burdekin River. This surface is a relict alluvial plain little incised by easterly flowing tributaries of the Burdekin River and has survived, essentially intact, from the early Pliocene. Geometry of the formation is established from some 2000 mineral exploration drill holes and seismic profiling. It has an average thickness of some 60 m, reaching a maximum of over 200 m. It blankets a pre-existing, low relief landscape in which a basement ridge divides it into two sub-basins that mirror the present drainage. The formation consists of poorly sorted sandstone with minor conglomerate and siltstone, and contains paleosol horizons with associated calcrete. Matrix supported sandstone in the succession, indicates deposition in part from hyperconcentrated flows. Sandstones generally show poorly defined planar layering as typical of ephemeral overbank and terminal splay sediment bodies but beds with cross-lamination, indicating fluvial channel bed forms, are also present. They are characterised by pore-filling silt and mud, largely emplaced by post-depositional infiltration, such that the unit produces essentially no groundwater. Facies attributes are consistent with fluvial deposition in ephemeral, dry climate, distributary system, with inefficient cross-drainage discharge that induced aggradation, resulting in a substantial sediment body perched in the landscape. Framework grain compositions show the formation to be mineralogically mature, representing erosional debris derived from intense weathering in an earlier climatic regime recorded, at least in part, by duricrust developed in the fluviatile–lacustrine Southern Cross Formation of Paleogene age. Such duricrust intervals are now upstanding in the landscape, representing erosional remnants from inverted relief developed in a mid-Cenozoic, pluvial, landscape cycle. Paleoclimatic signature of the Campaspe Formation extends the record of Pliocene aridity, widely recognised elsewhere in Australia, to northeast Queensland. In large part the landscape of the Charters Towers district is relict from the early Pliocene and is in the process of readjusting to more pluvial climatic regimes. By implication, Pliocene aridity has, on a small scale, exerted a strong influence on the present physiography of Australian landscapes.

Anatomical Models: A History of Disappearance?

In her introduction to Ephemeral Bodies: Wax Sculpture and the Human Figure, Roberta Panzanelli presents the history of wax as “a history of disappearance—transformed, softened, liquefied, and sometimes lost forever”. Wax objects are today seldom part of our environment. Apart from some popular museums, such as Tussaud’s, wax models are no longer used, no longer in vogue, and this is most particularly the case for wax anatomical models which used to be the pride of eighteenth- and nineteenth-...

Influence of spatio-temporal resource availability on mushroom mite diversity

Although biodiversity in nature is of fundamental importance because it improves the sustainability of ecosystems, communities of microscopic organisms are generally excluded from conservation targets for biodiversity. Here, I hypothesize that mushroom mite species richness is correlated with both spatial (i.e., mushroom size) and temporal (i.e., longevity of fruiting bodies) resource availability. I collected fruiting bodies in an old-growth forest over 4 years to collect mites and insects inhabiting the mushrooms. Mites were collected from 47 % of the fruiting bodies and approximately 60 % of the mite species were collected only once. Mite species richness was significantly correlated with the availability of long-lasting fruiting bodies. For example, bracket fungi contained more mite species than ephemeral fruiting bodies. Insect presence was also correlated with mushroom mite richness, probably as phoretic hosts and food resources for predacious mites. On the other hand, mushroom size seemed to be less important; small fruiting bodies sometimes harbored several mite species. Although mite species richness was correlated with mushroom species richness, mushroom specificity by mites was not clear except for a preference for long-lasting fruiting bodies. Therefore, I suggest that a constant supply of coarse woody debris is crucial for maintaining preferred resources for mushroom mites (e.g., bracket fungi) and their associated insects (mycophilous and possibly saproxylic insects).

Neotaphonomic measures of carnivore serial predation at Ngamo Pan as an analog for interpreting open-air faunal assemblages

Here I present a neotaphonomic account of natural bone accumulations that have resulted from carnivore serial predation at Ngamo Pan, a vast complex of seasonal water holes located in Hwange National Park, Zimbabwe. Reconstructing the taphonomic histories of faunal assemblages from open-air archaeological sites is burdened with a host of interpretive complications, and this study is offered as a referential means for evaluating instances where stone tools and bone accumulations are associated in apparent archaeological contexts. While the presence of stone tools implies some involvement on the part of humans, open-air sites near water would also have served as prime locations for serial predation by large carnivores to ambush prey—a situation that, over time, can mimic archaeological bone accumulations. The taphonomic and zooarchaeological signatures of carnivore serial predation at Ngamo Pan show marked similarities with the open-air faunal accumulation from Kalkbank, a late Pleistocene site in Limpopo Province, South Africa, located along the margins of a relict pan. Many potential archaeological sites within the interior of southern Africa dating to the Middle Stone Age are known from open-air settings near permanent or ephemeral bodies of water, and the ability to decipher between hominin and non-hominin carnivore involvement with bone accumulations is paramount in determining the hunting and scavenging behaviors of our early ancestors. As much of our understanding of hominin subsistence during the Middle Stone Age is drawn from coastal cave locations, this study is intended to encourage a broadening of our perspective on the taphonomic histories of faunal accumulations dating to the Middle Stone Age by incorporating supplementary evidence provided by these open-air sites.

Roberta Panzanelli, ed. Ephemeral Bodies: Wax Sculpture and the Human Figure. Los Angeles: Getty Research Institute, 2008. 328 pp.; 40 color and 87 halftone illustrations, notes, appendix, biographical notes on the contributors, illustration credits, index. $49.95.

Roberta Panzanelli, ed. <i>Ephemeral Bodies: Wax Sculpture and the Human Figure</i>. Los Angeles: Getty Research Institute, 2008. 328 pp.; 40 color and 87 halftone illustrations, notes, appendix, biographical notes on the contributors, illustration credits, index. $49.95.

:Ephemeral Bodies: Wax Sculpture and the Human Figure

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Ephemeral bodies: wax sculpture and the human figure: with a translation of Julius von Schlosser's History of portraiture in wax

Ephemeral bodies: wax sculpture and the human figure: with a translation of Julius von Schlosser's History of portraiture in wax

Evidence that Early Carboniferous ostracods colonised coastal flood plain brackish water environments

A study of the stable isotope composition ( δ 18O, δ 13C) of biogenic (ostracod, mollusc) and authigenic carbonates in the Ballagan Formation, Lower Carboniferous of Scotland, coupled with evidence from sedimentology and associated fossil fauna and flora, supports the argument that this formation was deposited in a coastal flood plain setting, in brackish (0.5 < 30‰ NaCl) and hypersaline (> 40‰ NaCl) waters, but in the absence of persistent normal marine conditions. The oxygen isotope data from the Ballagan Formation divide into three clusters: a diagenetic field defined by low δ 18O (< − 11‰ VPDB); an intermediary field ( δ 18O − 11‰ to − 9‰) composed of a mixture of known primary and secondary (diagenetic) carbonates; and samples within the range of − 9‰ to − 4‰ which, as far as we can ascertain, are largely unaltered. No samples give typical Early Carboniferous δ 18O marine values. Average marine carbonates from Europe have δ 18O between − 4‰ to − 3‰. The Ballagan Formation carbonates were probably deposited in evaporated freshwater and/or brackish water. This conclusion is supported by the presence of evaporites (gypsum, anhydrite, halite pseudomorphs) and common desiccation-cracked mudstone surfaces throughout the Ballagan Formation, suggesting conditions of fluctuating salinity in ephemeral bodies of water. The stable isotope data support the notion that the ostracod assemblages of the Ballagan Formation were colonising brackish water and hypersaline ecologies on a coastal flood plain during the Early Carboniferous, a stage of development that may have encouraged their colonisation of fully non-marine (limnetic) environments during the later Carboniferous. The ostracods include cytherellacean and kloedenellacean species known from marginal marine sites elsewhere, but probably tolerant of brackish water, podocopid species such as ‘ Bythocypris’ aequalis that may have been adapted for brackish water settings on coastal flood plains (ephemeral lakes and lagoons), and paraparchitacean-dominated assemblages that may signal harsh (hypersaline or desiccating) environments.

The phenology of Sarcosagium campestre observed over three years

A small number of lichens produce ephemeral fruit bodies that last for less than a year, they belong to genera such as Absconditella, Epigloea, Sarcosagium, Steinia, Thelocarpon and Vezdaea. Many are found in transient, terricolous, often man-made habitats and niches where competition is low. Poelt and Vežda (1990) have reviewed the sparse literature on ephemeral lichens. Since then, a two year study of Thelocarpon laureri in the Sheffield area (Gilbert 2001), has shown this species behaving as a spring ephemerophyte, the number of fruits peaking in April and May. Colonies persisted for 18 months (two fruiting periods). This short paper extends such observations to Sarcosagium campestre.

Vocal behaviors are related to nonrandom structure of anuran breeding assemblages in Guyana

An important problem in community ecology is that of identifying patterns of structure in data by employing null models. Null models use reiterative methods to generate large numbers of virtual communities that are compared with empirical assemblages. These allow detection of nonrandom structure of organization attributable to biotic and abiotic factors. We tested the hypothesis that vocal behaviors are related to nonrandom structure in frog breeding assemblages. Male frogs of many species gather at ephemeral bodies of water, and produce advertisement calls that primarily attract conspecific females who are ready to mate. We determined whether null models and multivariate techniques could test for nonrandom patterns in pond breeding assemblages comprised of 16 and 14 species in Guyana, South America. Comparisons of empirical data against two null models indicated that observed patterns of temporal, spatial, and spectral acoustic variables, and calling site use by heterospecific frogs were significantly nonrandom patterns. Observed patterns of spatial and calling site usage appeared to contribute to high species richness of these Neotropical frog breeding assemblages. Principal component analysis of advertisement calling variables of sympatric treefrogs (Hylidae) suggested that species differed in dominant frequency, fundamental frequency, pulse rate, note duration, call duration, and call rate. Discriminant function analysis of these same call variables in the numerically three most common treefrog species of the genus Scinax indicated that fundamental frequency and pulse rate alone separated the three species. Overall, the null models and multivariate statistical techniques suggested that nonrandom patterns of spatial and calling site usage were implicated in the apparent nonrandom structure of these Neotropical pond breeding anuran assemblages.

A model for the formation of transient event plumes above mid‐ocean ridge hydrothermal systems

Event plumes (or megaplumes) are ephemeral bodies of anomalously warm water which form in the water column above mid‐ocean ridges as the result of the catastrophic release of large volumes of hydrothermal fluid. During the formation of the largest event plumes, heat fluxes increase to at least 100 times those of a typical high‐temperature vent field. Recent observations reveal a strong association between event plumes and diking‐eruptive events. It has previously been suggested that event plumes are the result of increased fluxes throughout hydrothermal systems following a large increase in the permeability of a critical region. In this paper, an alternative model is explored whereby the volume of fluid expelled is not balanced by increased down‐flow but rather by the expansion of fluids near the base of the system. For most geologically plausible patterns of hydrothermal circulation, the fracturing and faulting associated with a diking event will result in a much larger decrease in the flow resistance of the upflow zone than the down‐flow zone. To balance fluxes, the pressure must decrease throughout the system. There is considerable evidence that the fluids near the base of mid‐ocean ridge hydrothermal convection cells lie near the two‐phase boundary for seawater and thus are very compressible. Simple calculations show that fluid expansion in a depressurized reaction zone can match the observed formation times and sizes of large event plumes only if the permeability of the upflow zone increases to very high values (∼10−9–10−10 m2) and if the plume is underlain by a sizable reaction zone containing at least 0.01–0.2 km3 of fluid at temperatures near the two‐phase curve. Fluid expansion in a smaller reaction zone is a plausible mechanism to incorporate a component of mature hydrothermal fluid into event plumes whose heat content comes primarily from cooling lava flows. It may also be responsible for smaller event plumes or temporal fluctuations in chronic plumes which are not linked to volcanic eruptions but which follow technically or magmatically induced increases in permeability.