Establishing a fossil record for the perianthless Piperales: Saururus tuckerae sp. nov. (Saururaceae) from the Middle Eocene Princeton Chert

Investigations of small permineralized flowers from the Middle Eocene Princeton Chert, British Columbia, Canada have revealed that they represent an extinct species of Saururus. Over 100 flowers and one partial inflorescence were studied, and numerous minute perianthless flowers are borne in an indeterminate raceme. Each flower is subtended by a bract, and flowers and bracts are borne at the end of a common stalk. Five stamens are basally adnate to the carpels. Pollen is frequently found in situ in the anthers. Examined under SEM and TEM, pollen grains are minute (6-11 μm), monosulcate, boat-shaped-elliptic, with punctate sculpturing and a granulate aperture membrane. The gynoecium is composed of four basally connate, lobed carpels with recurved styles and a single ovule per carpel. Flower structure and pollen are indicative of Saururaceae (Piperales), and in phylogenetic analyses using morphological characters, the fossils are sister to extant Saururus. The fossil flowers are described here as Saururus tuckerae sp. nov. These fossil specimens add to the otherwise sparse fossil record of Piperales, represent the oldest fossils of Saururaceae as well as the first North American fossil specimens of this family, and provide the first evidence of saururaceous pollen in the fossil record.     

贵州凤冈志留纪晚LLANDOVERY世植物黔羽枝研究综述

简要论述贵州凤冈志留纪Llandovery世晚期Pinnatiramosus qianensis Geng(黔羽枝)的研究历史、地层时代、主要特征、早期陆生维管植物起源和演化意义、争议焦点及其今后的研究途径和展望。P.qianensis代表了一类目前仍鲜为人知、由水生藻类植物向陆生环境过渡的植物类群,具有陆生维管植物某些重要特征,在后续演化过程中,可能是一类不成功的灭绝类群。由于P.qianensis的特有外部形态和复杂的内部解剖特征,对其认识引发了很大的争议,焦点集中在是否属于真正的志留纪植物(产出地层是否为志留纪Llandovery世晚期,是否属于这个时期的早期维管植物或植物根系)。作者认为:我国西南地区是探索早期陆生维管植物起源和早期演化的关键地区,通过一系列野外和室内研究,进一步强化对P.qianensis及其共生植物群的研究,并采用多学科交叉的方法,系统揭示P.qianensis的生物学属性、分类系统及其生态环境,在早期植物演化上提出新观点和演化模式,推进早期陆生维管植物起源、演化的研究。     

INVESTIGATIONS OF ANGIOSPERMS FROM THE EOCENE OF NORTH AMERICA: A CATKIN WITH JUGLANDACEOUS AFFINITIES

Three specimens of one type of fossil catkin from the Middle Eocene of Tennessee are excellently preserved and have been investigated morphologically. The flowers on these catkins are subtended by elongate, three-lobed bracts, are exclusively staminate, and have three conspicuous, obovate, perianth parts that bear large peltate scales. The stamens are well preserved and contain triporate pollen grains that are equivalent to the dispersed pollen genus Momipites. Floral morphology, cuticular features, and pollen indicate close affinities with the extant genera Engelhardia, Oreomunnea, and Alfaroa of the Juglandaceae; but because the fossil catkins are distinct and are a dispersed plant organ, they are placed in a new form genus: Eokachyra. These fossil flowers represent a rare opportunity to correlate the micro- and macrofossil record and to compare the relative rates of evolution of these features. The fossil catkins also demonstrate that much structural information may be gained from the study of fossil angiosperm flowers. The similarities between the staminate flowers of the fossil catkins and the staminate flowers of Engelhardia, Oreomunnea, and Alfaroa confirm the idea that this complex has had a long evolutionary history and suggest that the pollination system of certain extant genera was well developed during Middle Eocene times.     

Anatomically preserved leaves of the conifer Notophytum krauselii (Podocarpaceae) from the Triassic of Antarctica

Permineralized leaves of the Triassic podocarpaceous conifer Notophytum krauselii are described from the Fremouw Formation of Antarctica. The leaves are elongate and apetiolate with 8-12 parallel veins. The adaxial epidermis consists of rows of rectangular to pentagonal cells; the abaxial epidermis is papillate. Longitudinally oriented stomata occur on both surfaces. An adaxial palisade layer is present and auxiliary sclereids are common in the mesophyll. The vascular bundles have a weakly defined sheath and are flanked by transfusion tracheids. Bundles in the basipetal area of the leaf are capped by sclerotic tissue and subtended by resin canals. These leaves are superficially similar to those of the extant podocarp genus Nageia, but probably represent a distinct acquisition of this leaf type within the Podocarpaceae. Notophytum leaves are similar to the common compression fossil Heidiphyllum elongatum and may be closely related or even conspecific. Evidence from Antarctica suggests that Heidiphyllum and the seed cone Telemachus were produced by the same plant, and may be closely related to several other early Mesozoic conifers with multiveined leaves.     

SCIADOPITOPHYLLUM CANADENSE GEN. ET SP. NOV.: A NEW CONIFER FROM WESTERN ALBERTA

A new Sciadopitys-like conifer is described on the basis of compression fossils of shoots and leaves found at the Smokey Tower locality in western Alberta. The specimens consist of long, strap-like leaves attached in apparent whorls and subtended by groups of scale leaves. Other scale leaves are borne in loose spirals on the shoots between whorls. These specimens represent the first record of Sciadopitys-like foliage from western North America. Comparisons are made with extant and extinct species of the genus Sciadopitys (Siebold and Zuccarini, 1841) and with the widely distributed fossil genus Sciadopitytes (Goeppert and Menge, 1883).     

Morphometric variation in the papionin muzzle and the biochronology of the South African Plio‐Pleistocene karst cave deposits

Papionin monkeys are widespread, relatively common members of Plio‐Pleistocene faunal assemblages across Africa. For these reasons, papionin taxa have been used as biochronological indicators by which to infer the ages of the South African karst cave deposits. A recent morphometric study of South African fossil papionin muzzle shape concluded that its variation attests to a substantial and greater time depth for these sites than is generally estimated. This inference is significant, because accurate dating of the South African cave sites is critical to our knowledge of hominin evolution and mammalian biogeographic history. We here report the results of a comparative analysis of extant papionin monkeys by which variability of the South African fossil papionins may be assessed. The muzzles of 106 specimens representing six extant papionin genera were digitized and interlandmark distances were calculated. Results demonstrate that the overall amount of morphological variation present within the fossil assemblage fits comfortably within the range exhibited by the extant sample. We also performed a statistical experiment to assess the limitations imposed by small sample sizes, such as typically encountered in the fossil record. Results suggest that 15 specimens are sufficient to accurately represent the population mean for a given phenotype, but small sample sizes are insufficient to permit the accurate estimation of the population standard deviation, variance, and range. The suggestion that the muzzle morphology of fossil papionins attests to a considerable and previously unrecognized temporal depth of the South African karst cave sites is unwarranted. Am J Phys Anthropol 2010. © 2009 Wiley‐Liss, Inc.     

Early Oligocene Callitris and Fitzroya (Cupressaceae) from Tasmania

This paper documents Early Oligocene fossilized foliage and ovulate cones from Lea River, Tasmania and identifies them as belonging to two extant southern hemisphere Cupressaceae genera, Callitris and Fitzroya. Most importantly, it sheds some light on evolutionary trends within Callitris, a genus with numerous extant Australian species and two extant New Caledonian species. Callitris has a very poor fossil record and, because of the present absence of a molecular data set that includes all species, its phylogeny remains somewhat ambiguous. Although Fitzroya foliage has previously been described from a number of Tasmanian sites, this is the first recording of fertile material. The ovulate cones of the Callitris and Fitzroya macrofossils are characterized by bract-scale complexes in two whorls of three and are subtended by scale-like leaves in whorls of three. The fossilized foliage specimens consist of scale-like leaves in whorls of three. These morphological characteristics are only exhibited by three extant southern hemisphere cupressaceous genera, Callitris, Actinostrobus, and Fitzroya. The assignment of the fossils to extinct Callitris and Fitzroya species is made by comparisons with species from these three extant genera. Although much of the Lea River flora are wet rainforest taxa, the Callitris fossils have characteristics of both wet- and dry-adapted extant species.     

Evaluation of the fossil fish‐specific diversity in a chadian continental assemblage: Exploration of morphological continuous variation in Synodontis (Ostariophysi,Siluriformes)

In the fossil record, the quantification of continuous morphological variation has become a central issue when dealing with species identification and speciation. In this context, fossil taxa with living representatives hold great promise, because of the potential to characterise patterns of intraspecific morphological variation in extant species prior to any interpretation in the fossil record. The vast majority of catfish families fulfil this prerequisite, as most of them are represented by extant genera. However, although they constitute a major fish group in terms of distribution, and ecological and taxonomic diversity, the quantitative study of their past morphological variation has been neglected, as fossil specimens are generally identified based on the scarcest remains, that is, complete neurocrania that bear discrete characters. Consequently, a part of freshwater catfish history is unprospected and unknown. In this study, we explored the morphological continuous variation of the humeral plate shape in Synodontis catfishes using Elliptic Fourier Analysis (EFA), and compared extant members and fossil counterparts. We analysed 153 extant specimens of 11 Synodontis species present in the Chad basin, in addition to 23 fossil specimens from the Chadian fossiliferous area of Toros Menalla which is dated around 7 Ma. This highly speciose genus, which is one of the most diversified in Africa, exhibits a rich fossil record with several hundred remains mostly identified as Synodontis sp. The analysis of the outline of the humeral plate reveals that some living morphological types were already represented in the Chad Basin 7 My ago, and allows for the discovery of extinct species. Beside illuminating the complex Neogene evolutionary history of Synodontis, these results underline the interest in the ability of isolated remains to reconstruct a past dynamic history and to validate the relevance of EFA as a tool to explore specific diversity through time. J. Morphol. 277:1486–1496, 2016. © 2016 Wiley Periodicals, Inc.     

Increased Atmospheric SO2 Detected from Changes in Leaf Physiognomy across the Triassic–Jurassic Boundary Interval of East Greenland

The Triassic–Jurassic boundary (Tr–J; ∼201 Ma) is marked by a doubling in the concentration of atmospheric CO₂, rising temperatures, and ecosystem instability. This appears to have been driven by a major perturbation in the global carbon cycle due to massive volcanism in the Central Atlantic Magmatic Province. It is hypothesized that this volcanism also likely delivered sulphur dioxide (SO₂) to the atmosphere. The role that SO₂ may have played in leading to ecosystem instability at the time has not received much attention. To date, little direct evidence has been presented from the fossil record capable of implicating SO₂ as a cause of plant extinctions at this time. In order to address this, we performed a physiognomic leaf analysis on well-preserved fossil leaves, including Ginkgoales, bennettites, and conifers from nine plant beds that span the Tr–J boundary at Astartekløft, East Greenland. The physiognomic responses of fossil taxa were compared to the leaf size and shape variations observed in nearest living equivalent taxa exposed to simulated palaeoatmospheric treatments in controlled environment chambers. The modern taxa showed a statistically significant increase in leaf roundness when fumigated with SO₂. A similar increase in leaf roundness was also observed in the Tr–J fossil taxa immediately prior to a sudden decrease in their relative abundances at Astartekløft. This research reveals that increases in atmospheric SO₂ can likely be traced in the fossil record by analyzing physiognomic changes in fossil leaves. A pattern of relative abundance decline following increased leaf roundness for all six fossil taxa investigated supports the hypothesis that SO₂ had a significant role in Tr–J plant extinctions. This finding highlights that the role of SO₂ in plant biodiversity declines across other major geological boundaries coinciding with global scale volcanism should be further explored using leaf physiognomy.     

Tetrads in sporangia and spore masses from the Upper Silurian and Lower Devonian of the Welsh Borderland

Prior to the mid-Silurian, evidence for the earliest embryophytes comes from dispersed spores, particularly permanent tetrads, there being no fossils showing gross morphology or anatomy of the producers. The fragmentary coalified mesofossils described here from the uppermost Silurian (Pridoli) and basal Devonian (Lochkovian) of the Welsh Borderland contain tetrads assigned to Tetrahedraletes, Velatitetras and Cheilotetras. These spores together with examples from spore masses have been examined by scanning and transmission electron microscopy and display diversity in ultrastructure of the exospore and envelope. Tetrads have been found, together with a putative elater, in the forking apex of an axial Lochkovian fossil, named Grisellatheca salopensis gen. et sp. nov., that anatomically, apart from spore characters, reveals no unequivocal evidence for hepatic affinity. The remaining fossils are equally as uninformative as regards affinity. Tetrads with ornamented envelopes are recorded in an isolated discoidal sporangium and in the bases of incomplete sporangia borne terminally on a bifurcating axis. Both ornament and ultrastructure suggest that the spores belong to quite distinct species within Velatitetras. Tetrahedraletes is recorded in an incomplete sporangium subtended by a forking axis, in which no cellular detail is preserved. Naked unfused tetrads also assigned to Tetrahedraletes are recorded in spore masses from both localities and again exospore ultrastructure demonstrates diversity. A final Lochkovian sporangium contains naked tetrads with sporadic Papiculate ornament and shows a unique trilayered exospore. Comparisons of exospore ultrastructure in these tetrads, which it is argued are mature and dispersed as such, provide no unequivocal evidence for affinities, be they tracheophyte or bryophyte. The bifurcating sporophytes are evidence against similarities with extant bryophytes. It is concluded that these very fragmentary fossils derive from small plants comprising relict populations of the vegetation that flourished on land in turfs through the greater part of the Ordovician and early Silurian, but that was gradually replaced by the tracheophytes.     

Life cycle assessment of biofuels from Jatropha curcas in West Africa: a field study

In recent years, liquid biofuels for transport have benefited from significant political support due to their potential role in curbing climate change and reducing our dependence on fossil fuels. They may also participate to rural development by providing new markets for agricultural production. However, the growth of energy crops has raised concerns due to their high consumption of conventional fuels, fertilizers and pesticides, their impacts on ecosystems and their competition for arable land with food crops. Low-input species such as Jatropha curcas , a perennial, inedible crop well adapted to semiarid regions, has received much interest as a new alternative for biofuel production, minimizing adverse effects on the environment and food supply. Here, we used life-cycle assessment to quantify the benefits of J. curcas biofuel production in West Africa in terms of greenhouse gas emissions and fossil energy use, compared with fossil diesel fuel and other biofuels. Biodiesel from J. curcas has a much higher performance than current biofuels, relative to oil-derived diesel fuels. Under West Africa conditions, J. curcas biodiesel allows a 72% saving in greenhouse gas emissions compared with conventional diesel fuel, and its energy yield (the ratio of biodiesel energy output to fossil energy input) is 4.7. J. curcas production studied is eco-compatible for the impacts under consideration and fits into the context of sustainable development.     

Role of carnivores in the accumulation of the Sterkfontein Member 4 hominid assemblage: a taphonomic reassessment of the complete hominid fossil sample (1936-1999)

New taphonomic data on the Sterkfontein Member 4 (South Africa) fossil hominid assemblage are presented. The previous estimate of hominid individuals represented in the deposit (45) is increased to 87. New minimum numbers of hominid skeletal elements are provided, and incidences of bone surface damage inflicted by prehistoric biological agents are summarized. The hominid sample from Member 4 is composed predominately of gnathic remains and has a paucity of postcrania. This dearth of postcrania limits, to some extent, inferences about the formation of the Sterkfontein assemblage. However, carnivore tooth marks on some fossil specimens and an overall broad similarity in patterns of skeletal part representation between Sterkfontein and primate bone assemblages created by extant carnivores suggest that carnivores did have some involvement in the accumulation of the fossil hominid assemblage. Thus, this study provides support for the “carnivore‐collecting hypothesis” of Brain (Brain [ 1981 ] The Hunters or the Hunted? Chicago: University of Chicago Press), which implicates large carnivores as prominent collecting agents of hominid body parts in Sterkfontein Member 4. Evidence of bone surface damage is, however, too scant to make confident inferences about specific carnivore taxon/taxa involved in hominid bone collection at the site. Am J Phys Anthropol, 2004. © 2004 Wiley‐Liss, Inc.     

Two early eudicot fossil flowers from the Kamikitaba assemblage (Coniacian,Late Cretaceous) in northeastern Japan

Two new fossil taxa referable to the basal eudicot grade are described from the Kamikitaba locality (ca. 89 MYBP, early Coniacian: Late Cretaceous) of the Futaba Group in Japan. These charcoalified mesofossils exhibit well-preserved three-dimensional structure and were analyzed using synchrotron-radiation X-ray microtomography to document their composition and internal structure. Cathiaria japonica sp. nov. is represented by infructescence segments that consist of an axis bearing three to four fruits. The capsular fruits are sessile and dehiscent and consist of a gynoecium subtended by a bract. No perianth parts are present. The gynoecium is monocarpellate containing two pendulous seeds. The carpel is ascidiate in the lower half and conduplicate in the upper part, and the style is deflected abaxially with a large, obliquely decurrent stigma. Pollen grains are tricolpate with a reticulate exine. The morphological features of Cathiaria are consistent with an assignment to the Buxaceae s. l. (including Didymelaceae). Archaestella verticillatus gen. et sp. nov. is represented by flowers that are small, actinomorphic, pedicellate, bisexual, semi-inferior, and multicarpellate. The floral receptacle is cup shaped with a perigynous perianth consisting of several tepals inserted around the rim. The gynoecium consists of a whorl of ten conduplicate, laterally connate but distally distinct carpels with a conspicuous dorsal bulge, including a central cavity. The styles are short, becoming recurved with a ventrally decurrent stigma. Seeds are ca. 10 per carpel, marginal, pendulous from the broad, oblique summit of the locule. Pollen grains are tricolpate with a reticulate exine pattern, suggesting a relationship to eudicots. The morphological features of Archaestella indicate a possible relationship to Trochodendraceae in the basal grade of eudicots. The fossil currently provides the earliest record of the family and documents the presence of Trochodendraceae in eastern Eurasia during the middle part of the Late Cretaceous.     

A Middle-Late Eocene inflorescence of Caryophyllaceae from Tasmania, Australia

A new genus and species (Caryophylloflora paleogenica genus and species nova G. J. Jord. & Macphail) are proposed for a fossil inflorescence found in Middle-Late Eocene sediments at Locharbour, northeastern Tasmania, Australia. A parsimony analysis of 75 extant species of the order Caryophyllales and five outgroups placed the fossil within Caryophyllaceae, either subfamily Alsinoideae or Caryophylloideae. The analysis used molecular (rbcL and/or matK), morphological, and anatomical data for the extant species and morphological data for the fossil. Tests on extant species imply that the placement of the fossil should be convincing. The fossil appears to be of a lineage distinct from any extant Australian Caryophyllaceae. In situ pollen are consistent with the form species, Periporopollenites polyoratus. This relatively simple pollen type first appears in Australia and New Zealand in the Late Cretaceous, the oldest known record of the Caryophyllaceae. The last appearance of P. polyoratus in Australia is in the Oligocene, and extant Australian members of the Caryophyllaceae are best interpreted as having evolved from species that dispersed from elsewhere during the Neogene or Quaternary.     

Hemerodromiinae (Diptera: Empididae): a tentative phylogeny and biogeographical discussion

A cladistic analysis of adult morphological characters was used to hypothesize phylogenetic and zoogeographical relationships in Hemerodromiinae (Diptera: Empididae). Afrodromia Smith, Drymodromia Becker and an undescribed Chilean genus subtended a sister‐group relationship between the tribes Chelipodini and Hemerodromiini. Chelipodozus Smith and an undescribed Australian genus were supported only weakly in Hemerodromiini, and are regarded as incertae sedis within Hemerodromiinae. In Chelipodini, Anaclastoctedon Plant and an undescribed Australian genus subtended all others that form two sister‐group clades. (i) A widespread Chelipoda‐like group comprising Achelipoda Yang, Zhang & Zhang, Ptilophyllodromia Bezzi, Chelipoda Macquarts.s. and Phyllodromia Zetterstedt s.s. has a worldwide distribution, excepting the Afrotropical, considered to date from before or during the early phase of Gondwanan fragmentation. Phyllodromia s.s. is an exclusively Palaearctic genus of doubtful validity, to which Southern Hemisphere forms have been assigned incorrectly. Ptilophyllodromia Bezzi syn.n . is regarded as a junior synonym of Chelipoda, with the included species relegated to a species group. (ii) An austral Chelipoda‐like group confined to New Zealand, New Caledonia, Lord Howe Island and Vanuatu, includes Monodromia Collin and species currently incorrectly assigned to Chelipoda and Phyllodromia. The group is hypothesized as a relictual Gondwanan element that has survived Oligocene drowning as metapopulations persisting in situ on ephemeral islands along arcs, ridges and buoyant crustal blocks overlying hot spots in New Zealand and the Southwest Pacific. In the tribe Hemerodromiini, many Southern Hemisphere species assigned currently to Hemerodromia Meigen, Cladodromia Bezzi and Neoplasta Coquillett require reassignment. The sister‐group relationship between the southern African endemic Afrodromia and other Hemerodromiinae is viewed as evidence of early divergence of Hemerodromiinae and Empidinae by the early Cretaceous, pre‐dating major Gondwanan fragmentation. An assessment of fossil forms indicated that Chelifera detestata (Meunier) from Eocene/Oligocene Baltic amber is the only genuine described fossil representative of Hemerodromiinae.     

The mode of origin of root buds and root sprouts in the clonal tree Sassafras albidum (Lauraceae)

The developmental anatomy of root buds and root sprouts was examined in the clonal tree Sassafras albidum. Root samples from 13 clones that varied widely in age and vigor were sectioned and two types of buds were found, "additional" buds and "reparative" buds. Additional buds form during the early growth of uninjured roots and they perennate by growing outwards in concert with the vascular cambium such that bud traces are produced in the secondary xylem. Reparative buds form de novo in response to senescence, injuries, or other types of disturbance. Reparative buds were found on the roots of seven of the clones, whereas additional buds were found on the roots of all 13 clones. The reparative buds had originated in the proliferated pericycle, where they were subtended by sphaeroblasts, or spherical nodules of wood. Few of the reparative buds were vascularized and none were connected with the vasculature of their parent roots. In contrast, most of the additional buds were vascularized, and the leaf traces of several of the additional buds appeared to be contiguous with the conducting xylem of their parent roots. To determine whether both bud types were functional, 82 field-collected root sprouts and 44 incubation-induced sprouts were sectioned at the root-sprout junction and examined for evidence relating to their mode of origin. None of the sprouts were subtended by sphaeroblasts, but 98% were subtended by bud traces, which indicated that they had originated from additional buds. Although reparative buds were more common than additional buds on some of the root samples, they appear to be dysfunctional at sprouting. Additional buds, on the other hand, are able to sprout both as a normal part of clonal spread and from root cuttings.     

Early Miocene catarrhine dietary behaviour: the influence of the Red Queen Effect on incisor shape and curvature

The early Miocene catarrhine fossil record of East Africa represents a diverse and extensive adaptive radiation. It is well accepted that these taxa encompass a dietary range similar to extant hominoids, in addition to some potentially novel dietary behaviour. There have been numerous attempts to infer diet for these taxa from patterns of dental allometry and incisor and molar microwear, however, morphometric analyses until now have been restricted to the post-canine dentition. It has already been demonstrated that given the key functional role of the incisors in pre-processing food items prior to mastication, there is a positive correlation between diet and incisal curvature (Deane, A.S., Kremer, E.P., Begun, D.R., 2005. A new approach to quantifying anatomical curvatures using High Resolution Polynomial Curve Fitting (HR-PCF). Am. J. Phys. Anthropol. 128(3), 630-638.; Deane, A.S., 2007. Inferring dietary behaviour for Miocene hominoids: A high-resolution morphometric approach to incisal crown curvature. Ph.D. Dissertation. The University of Toronto.). This study seeks to re-examine existing dietary hypotheses for large-bodied early Miocene fossil catarrhines by contrasting the incisal curvature for these taxa with comparative models derived from prior studies of the correlation between extant hominoid incisor curvature and feeding behaviour. Incisor curvature was quantified for 78 fossil incisors representing seven genera, and the results confirm that early Miocene fossil catarrhines represent a dietary continuum ranging from more folivorous (i.e., Rangwapithecus) to more frugivorous (i.e., Proconsul) diets, as well as novel dietary behaviours that are potentially similar to extant ceboids (i.e., Afropithecus). Additionally, early Miocene fossil catarrhine incisors are less curved than extant hominoid incisors, indicating a general pattern of increasing mesio-distal and labial curvature through time. This pattern of morphological shifting is consistent with the Red Queen Effect (Van Valen, L., 1973. A new evolutionary law. Evol. Theory 1, 1-30), which predicts that taxa that are removed from one another by geological time, although potentially having similar diets, may exhibit differing degrees of a similar dietary adaptation (i.e., differing degrees of incisal curvature).     

Sedimentary records of carbonaceous particles from fossil fuel combustion

Carbonaceous particles produced by fossil fuel combustion can be found in considerable amounts in recent lake sediments. As these particles contain elemental carbon they are resistant to chemical decomposition and therefore both well preserved in sediments and possible to quantify. Sediment samples can be oxidized with H₂O₂ and digested with HF without the particles being destroyed. The pioneers in studying carbonaceous particles in lake sediments in relation to fossil fuel combustion were J. J. Griffin and E. D. Goldberg. They measured elemental carbon concentrations in Lake Michigan sediments, mainly by infrared assay. On the basis of these analyses, size distribution measurements and also morphological studies of single particles they concluded that the carbonaceous particle record reflected the onset of industrial activity and the increased intensities of fossil fuel combustion during the twentieth century. Similar results have been obtained from another lake in the USA by B. K. Kothari and M. Wahlen. We have counted spherical carbonaceous particles (larger than 5–10 µm), which are characteristic for oil and coal burning, in several lake sediments. In Swedish lakes, the annual accumulation of coarse carbonaceous spheres in varved sediments and the concentration stratigraphy in non-varved sediments, follow the same main pattern as statistical data for the Swedish coal and oil combustion over the last two centuries. Coarse carbonaceous spheres in two sediment profiles from Scottish lakes have also been counted. As for the USA and Sweden the sedimentary record was found to reflect the history of fossil fuel combustion.     

Brief Communication: Calculating hominin and nonhuman anthropoid femoral head diameter from acetabular size

Femoral head size provides important information on body size in extinct species. Although it is well‐known that femoral head size is correlated with acetabular size, the precision with which femoral head size can be estimated from acetabular size has not been quantified. The availability of accurate 3D surface models of fossil acetabular remains opens the possibility of obtaining accurate estimates of femoral head size from even fragmentary fossil remains [Hammond et al.,: Am J Phys Anthropol 150 (2013) 565–578]. Here we evaluate the relationship between spheres fit to surface models of the femoral head and acetabulum of a large sample of extant anthropoid primates. Sphere diameters are tightly correlated and scale isometrically. In spite of significant taxonomic and possibly functional differences in the relationship between femoral head size and acetabulum size, percent prediction errors of estimated femoral head size remain low regardless of the taxonomic composition of the reference sample. We provide estimates of femoral head size for a series of fossil hominins and monkeys. Am J Phys Anthropol 155:469–475, 2014. © 2014 Wiley Periodicals, Inc.     

A new species, Dicheirinia panamensis, and new records of rust fungi from Panama

Based on a recent fieldwork in Panama, 25 species of rust fungi and several new hosts are reported for the first time from this country. Among the new records is one new species, Dicheirinia panamensis on Cojoba rufescens (Fabaceae). It differs from known species in the genus Dicheirinia by the presence of uredinia and telia without paraphyses, irregularly tuberculate urediniospores with two germ pores on the flattened sides, and tuberculate teliospores formed by three probasidial cells, subtended by a pedicel with three hyaline, apical cells. Taxonomical novelty: Dicheirinia panamensis J.R. Hern.,M. Piepenbr. and Vega Rios.