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The Swedenborg whale Balaena swedenborgii Liljeborg, 1867, is a baleen whale species believed to have existed in the North Sea from the period when the inland ice melted around 13,000 before present (BP) until about 8000 years ago. The first bones attributed to this species were found in Sweden in 1705. When whale remains were discovered on the Swedish west coast during the extension work of a motorway extension, it was speculated that this could be a specimen of the extinct Swedenborg whale. The bones were found 72 m above the present-day sea level embedded in glacial mud. Shelly remains of marine organisms were present in the deposit surrounding the whale-fall, and sediments with the associated specimens were therefore collected for further analyses. We applied radiocarbon dating, thin sectioning, morphological analyses, ancient DNA typing and analyses of the associated shelly assemblage in an interdisciplinary effort to understand the circumstances of this fossil whale-fall. Our results show that the whale is not the putative species B. swedenborgii, but a bowhead whale Balaena mysticetus. The results also indicate that the whale must have been rapidly covered by glacial sediments, highlighting the speed of the deglacial process in the area.  相似文献   

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Zygophyseter varolai , a new genus and species of Physeteroidea (Cetacea, Odontoceti), is based on an almost complete skeleton from the Late Miocene (Tortonian) in southern Italy. The extreme elongation of the zygomatic process of the squamosal and the circular supracranial basin (probably for housing the spermaceti organ) delimited by a peculiar anterior projection of the supraorbital process of the right maxilla are the most distinctive features of this bizarre sperm whale. Large body size, large teeth present in both lower and upper jaw, and anteroposteriorly elongated temporal fossa and zygomatic process of the squamosal indicate that this cetacean (for which we suggest the English common name killer sperm whale) was an active predator adapted to feeding on large prey, similarly to the extant killer whale ( Orcinus orca ). A phylogenetic analysis reveals that Zygophyseter belongs to a Middle–Late Miocene clade of basal physeteroids, together with Naganocetus (new genus for the type of ' Scaldicetus ' shigensis ). Moreover, the phylogenetic analysis shows evidence of a wide physeteroid radiation during the Miocene and that the extant Physeter and Kogia belong to two distinct families that form a clade representing the crown-group Physeteroidea.  © 2006 The Linnean Society of London, Zoological Journal of the Linnean Society , 2006, 148 , 103–131.  相似文献   

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In previous article, we showed a log-normal distribution of boron and lithium in human urine. This type of distribution is common in both biological and nonbiological applications. It can be observed when the effects of many independent variables are combined, each of which having any underlying distribution. Although elemental excretion depends on many variables, the one-compartment open model following a first-order process can be used to explain the elimination of elements. The rate of excretion is proportional to the amount present of any given element; that is, the same percentage of an existing element is eliminated per unit time, and the element concentration is represented by a deterministic negative power function of time in the elimination time-course. Sampling is of a stochastic nature, so the dataset of time variables in the elimination phase when the sample was obtained is expected to show Normal distribution. The time variable appears as an exponent of the power function, so a concentration histogram is that of an exponential transformation of Normally distributed time. This is the reason why the element concentration shows a log-normal distribution. The distribution is determined not by the element concentration itself, but by the time variable that defines the pharmacokinetic equation.  相似文献   

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Bryde's-like whales are a complex of medium-sized baleen whales that occur in tropical waters of all three major ocean basins. Currently, a single species of Bryde's whale, Balaenoptera edeni Anderson, 1879, is recognized, with two subspecies, Eden's whale, B. edeni edeni and Bryde's whale, B. edeni brydei (Olsen, 1913), although some authors have recognized these as separate species. Recently, a new, evolutionarily divergent lineage of Bryde's-like whale was identified based on genetic data and was found to be restricted primarily to the northern Gulf of Mexico (GOMx). Here, we provide the first morphological examination of a complete skull from these whales and identify diagnostic characters that distinguish it from the other medium-sized baleen whale taxa. In addition, we have increased the number of genetic samples of these Bryde's-like whales in the GOMx from 23 to 36 individuals, all of which matched the GOMx lineage. A review of Bryde's-like whale records in the Caribbean and greater Atlantic supports an isolated distribution for this unique lineage, augmenting the genetic and morphological body of evidence supporting the existence of an undescribed species of Balaenoptera from the Gulf of Mexico.  相似文献   

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Members of Calamyzinae, a clade of free‐living and ectoparasitic chrysopetalids, are mainly associated with deep‐sea chemosynthetic environments. The three currently known free‐living calamyzin species are placed in Vigtorniella. A new free‐living calamyzin species similar to these is described here. Phylogenetic analyses of Calamyzinae using mitochondrial (cytochrome c oxidase subunit I and 16S rDNA) and nuclear (Histone H3 and 18S rDNA) loci showed that Vigtorniella and the new species form a grade with respect to an ectoparasitic clade, requiring two new genera to be erected. All free‐living calamyzins show a similar anterior end and chaetal morphology. Micospina auribohnorum gen. et sp. nov. is described for the small‐bodied new species from deep‐sea whale falls off California and methane seeps off Costa Rica. The maximum‐likelihood and Bayesian analyses show Micospina gen. nov. as sister to the ectoparasitic clade. Boudemos gen. nov. is named for the clade of two larger‐bodied species: Boudemos flokati gen. et comb. nov. and Boudemos ardabilia gen. et comb. nov., which is sister group to all other Calamyzinae. Vigtorniella is retained for the type species, Vigtorniella zaikai (Kiseleva, 1992), with the adults found amongst bacterial mats at the boundary of the hydrogen sulphide zone in the Black Sea. Micospina gen. nov., Boudemos gen. nov., and Vigtorniella form a grade of free‐living taxa that is associated with feeding on organic‐enriched sediments, and the latter two taxa display ontogenetic jaw change. Jaws are absent in Micospina auribohnorum gen. et sp. nov. and most of the calamyzin clade of parasitic forms.  相似文献   

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We examined leaf and pollen histochemical properties in Parietaria L. and measured trace element concentrations in urban sites in Palermo, Sicily, affected by different stress valence levels. Urban pollution affects histochemistry macro-, micro-, and toxic element concentrations in Parietaria. We therefore decided to determine whether this plant can be used as a simple biomonitor or bioaccumulator of pollution contaminants. Samples were collected at various sites in different periods. An increase in phenolic compound levels was a result of the impact of pollution. Histochemical characteristics and trace element concentrations varied according to the period, but not to the place, of sampling. Pollutant concentrations were the highest in the month of February 2002. Trace metal concentrations were the lowest in July. Our investigations have confirmed that Parietaria L. can be used to study the effects of trace elements in the atmosphere in urban sites; in fact, they are veritable accumulators, given that elevated levels of pollutants can be found on their structures with no visible morphological effects. There are differences in accumulation capacity according to the trace elements studied. Pollution alters the content of phenolic compounds and chemical elements in Parietaria L.  相似文献   

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We present the study of rodents and insectivores from the 1995 season of excavation at the early Late Pleistocene site of Bois Roche (Charente, France). The site is a small cave with a low ceiling, used as a den by hyenas. It contains a large herbivore assemblage (mainly bovids and equids) with a smaller representation of medium-size taxa (cervids), many microvertebrates, abundant coprolites and deciduous hyena teeth, and a few lithic artifacts (Middle Paleolithic) introduced into the cave by gravity and slope wash. The rodent fauna consists of Eliomys quercinus cf. quercinus, Apodemus sp., Microtus gregalis, Microtus oeconomus, Arvicola terrestris and Dicrostonyx torquatus. Insectivores are represented by Neomys cf. fodiens. The most common species is M. gregalis which forms 93.7% of the total MNI. The micromammal fauna suggests an open landscape, with some vegetation mainly of the steppe or tundra type, with areas of water and more wet vegetation and some areas with trees. The micromammal association of Bois Roche is characteristic of a cold or very cold dry climate.  相似文献   

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Two single assemblages of cereals and chaff from the oppidum Bibracte, (Burgundy, France), give evidence of cereal trade, food supply and crop processing in late Celtic and early Roman times. The first deposit consists mainly of Triticum dicoccon chaff which was buried in a wooden box near the sanctuary of La Terrasse. The second assemblage was a store of different wheats and barley excavated in a Roman cellar at the Pature du Couvent. The analyses of these finds are presented, and recent archaeobotanical research at Mont Beuvray is summarized.  相似文献   

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Abstract

The Tayassuidae is one of the first families of North American immigrant mammals that arrived into South America during the ‘Great American Biotic Interchange’. They have been found associated with Late Cenozoic deposits mainly in Argentina and Brazil, but also in Uruguay, Bolivia, Colombia, Peru and Venezuela. Theirs records within Argentina come from the Pampean Region, Mesopotamia and north-central region. Here, we report the first record of P. carlesi with precise stratigraphic (26.630 ± 370 14C years BP, Late Pleistocene) data in Argentina, precisely from the Chacoan region. This specimen represents the most complete fossil material of this extinct species, increasing its morphological and morphometrical knowledge, and it provides relevant ecological and climatic information. From a palaeoenvironmental point of view, the fauna registered in this paleontological site, includes taxa mainly adapted to open or semi-open and arid or semi-arid environments. The bearing sediments and the peculiarities of the faunal assemblages, as well as the chronological data, allow confirming that arid and semiarid conditions, with scarce or absent vegetation cover were developed in this area of Argentina during the last part of MIS 3 and beginning of MIS 2. These environmental conditions favored the settlement of megamammals adapted to open environments.  相似文献   

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A new genus and species of Ziphiidae, Dagonodum mojnum gen. nov., sp. nov., from the upper Miocene Gram Formation (c. 9.9–7.2 Ma) represents the first occurrence of the family in Denmark. This long‐snouted ziphiid is characterized by two pairs of mandibular tusks, the Eustachian outlet that approximately levels with the dorsalmost margin of the posterior portion of the involucrum, and the left trapezoid nasal with a posteromedial projection into the frontal. A phylogenetic analysis including 25 species and 69 characters was conducted. Dagonodum mojnum is placed in a basal ziphiid clade as the sister taxon of Messapicetus. The specimen is probably a male, because it has enlarged tusks. Alternatively, females could also be involved in fights and develop erupted tusks as in the extant Berardius. Although less well supported, this interpretation proposes that aggressive interactions were not restricted to males in stem‐ziphiids. With a thickened thyrohyal and the presence of a precoronoid crest, D. mojnum was able to use suction feeding, but was less specialized to it compared to extant ziphiids. The elongated neck of D. mojnum less optimized to perform deep dives, and the shallow depth at which the Gram Formation was deposited corroborates the hypothesis that at least part of the stem‐ziphiids were not regular deep divers.  相似文献   

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根据1987年以来野外调查资料,分析了西藏已知蠓类种类、地理分布及区系特点。目前已知西藏蠓科昆虫4亚科14属31亚属151种,占我国已知蠓类(约1100种)的13.73%。其中,仅在西藏有分布并以西藏为模式产地的特有种为99种,占西藏已知蠓种的65.56%。区系分析表明,在所报道的西藏蠓科151种中,古北界15种,占西藏蠓种总数的9.93%,均分布于青藏区青海藏南亚区;东洋界131种,占西藏蠓种总数的86.75%,有105种分布于西南区喜马拉雅亚区,有18种分布于西南区西南山地亚区,有8种分布于喜马拉雅亚区和西南山地亚区;两界均有分布的有5种,占西藏蠓种总数的3.31%。  相似文献   

15.
《Comptes Rendus Palevol》2014,13(8):681-690
For the first time, the fossil herpetofauna from the Middle and Late Pleistocene of Scladina and Sous-Saint-Paul caves (Sclayn, Belgium) is described. The amphibians and squamate reptiles are represented by one salamander (Salamandra salamandra), three anurans (Pelodytes punctatus, Bufo bufo and Rana temporaria), two lizards (Lacerta cf. agilis and Anguis fragilis) and two snakes (Zamenis longissimus and Vipera cf. berus). The occurrence of the Parsley Frog (Pelodytes punctatus) and the Aesculapian Snake (Zamenis longissimus), which are not currently represented in Belgium, is of particular interest. Scladina also represents one of the northernmost fossil mentions for the Fire Salamander (Salamandra salamandra) although it is within its current distribution in Europe. Finally, the presence of the Adder (Vipera cf. berus) is very probably attested in Scladina whereas today this snake is infrequent and classified as endangered in Belgium.  相似文献   

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The PP10 stalagmite from Poleva Cave provides a Late Pleistocene and Holocene isotopic record characteristic for the SW of Romania, a sub-Mediterranean climatic region. The speleothem was dated by eight TIMS and one alpha U-series dates which showed that it was precipitated between ∼ 75 ka and ∼ 2 ka with at least two hiatuses. The basal sector of the stalagmite showed a slow-growing regime of ∼ 0.26 cm/ka, while the upper one grew relatively fast with about 5 cm/ka. The temporal resolution for the isotopic sampling is thus ∼ 2 ka/sample for the lower sector, and ∼ 150 years/sample for the upper one. The relationship between δ18O and temperature was found positive. The isotopic record of the lower sector shows two marked cold intervals during ∼ 67 and 58 ka and ∼ 40–35 ka, respectively, which correlate well with the Villars and Soreq records. The upper sector record is so far the most detailed Holocene isotopic record in Romania and the only one available for the regions located at the exterior of the Carpathians Range. The signal shows a gradual warming after the GS1 event punctuated by several cold events at ∼ 8, 7.2 and 4.2 ka and also by warm oscillations centered at about 5.2 and 3.3 ka. The results seem to indicate that if the North-Atlantic first-order signals may extend well to the south-eastern Europe, their amplitude and general trend may be diminished by the interferences with the Mediterranean circulation.  相似文献   

17.
Here we present a revision of the fossil record of chitons (Mollusca, Polyplacophora) of Late Pleistocene and Holocene marine deposits of Uruguay and discuss their potential for palaeoenvironmental reconstruction. Chitons were recorded as isolated valves in bivalve- and gastropod-rich assemblages. They are represented by the species Chaetopleura angulata (Spengler), C. isabellei (d’Orbigny), C. asperrima (Gould) and Ischnochiton striolatus (Gray). The last two species are recorded for the first time as fossils not only in Uruguay but also in South America. Exclusively recorded for the Late Pleistocene is the warm water species I. striolatus, whose current southern range limit is located in Santa Catarina, Brazil. Higher temperatures than at present are inferred for the Uruguayan coast during the Late Pleistocene, probably driven by the southward influence of the warm Brazilian Current along the eastern margin of South America. Chitons from Holocene deposits show a wider geographic distribution along the Uruguayan coast in comparison to current distributions. They are recorded where an estuarine and eurihaline fauna lives today, which suggests the former existence of marine conditions. This is explained by the westward displacement of the marine front in the Uruguayan coast during the Holocene transgressive events. Chitons have proven to be useful palaeoenvironmental proxies for the reconstruction of salinity and temperature trends in the Uruguayan coast during the climatic oscillations of the Late Pleistocene and Holocene epochs. As such, their patterns of distribution are related to the recent physical evolution of the Southwestern Atlantic Ocean.  相似文献   

18.
Vitamin A and E concentrations were determined in liver (n = 51), blubber (n = 23) and serum (n = 53) of subsistence-hunted bowhead whales (Balaena mysticetus), between 1998 and 2001. Retinol and alpha-tocopherol were the major forms of vitamins A and E detected, respectively. Liver contained the highest mean concentrations of vitamin A, followed by epidermis, blubber, and serum. Liver also contained the highest mean concentration of vitamin E, followed by serum, epidermis, and blubber. Stratification of retinol and tocopherol was examined throughout the blubber cores collected. Retinol concentrations were significantly higher in the epidermis than in the deeper blubber layers. Tocopherol concentrations were similar for epidermis and the intermediate layer of blubber. Both the epidermis and the intermediate layer of blubber had significantly higher tocopherol concentrations than the innermost and outermost blubber layers. Vitamin A and E concentrations were investigated with respect to gender and reproductive status of females (males, non-pregnant females, pregnant females), age groups and season of harvest. Certain persistent organic contaminants are known to have a negative effect on retinol concentration in serum of pinnipeds and cetaceans. Bowhead whales have relatively low concentrations of organochlorines (OCs) in comparison to other mysticete species. The relationships between serum, liver and blubber retinol and serum and blubber OC concentrations were examined with no significant correlations noted.  相似文献   

19.
Abstract: Cirripede remains (Thoracica, Verrucomorpha), found associated with the mosasaur Prognathodon waiparaensis  Welles and Gregg, 1971 in glauconitic sands of the Late Cretaceous Conway Formation exposed along the Waipara River bank (mid‐Canterbury, New Zealand), are identified as a new species, Verruca sauria sp. nov. On the basis of taphonomy, it is deduced that these verrucids grew on a postmortem accumulation of mosasaur bones under very quiescent conditions. The current amphitropical distribution of the earliest known verrucids, i.e. V. sauria sp. nov., V. prisca  Bosquet, 1854 , V. pusilla  Bosquet, 1857 and V. tasmanica  Buckeridge, 1983 , is rationalized in the light of Tethyan palaeogeography.  相似文献   

20.
The deposits of the Carnian Kas?mlar Formation within the Taurus Platform Units of south‐western Turkey represent an important archive of a Late Triassic ecosystem. New palaeontological information was obtained by analysing the Kasimlarceltites mass occurrence, located within the Kas?mlar Formation and named after the Lower Carnian (Julian) ammonoid genus Kasimlarceltites. This is the dominant taxon (> 94%) within the mass occurrence: nearly 775 million ammonoids and 50 million gastropods were extrapolated for the whole extension (at least 5 km2) of the Kasimlarceltites beds. This calculation is one of the main findings within this study, as it is the first time that such a fossil mass occurrence was quantified. Additionally, orientation measurements of the planispiral ammonoids and the helical gastropods enabled reconstructing the history of the mass occurrence and interpreting the underlying transport mechanisms. Further taphonomic aspects (e.g. biofabric, preservation, bioerosion or genetic classification) as well as comparisons with samples of the same acme zone from different localities near A?a?iyaylabel (AS IV, KA I‐II) point to a two‐phased genetic history. Accordingly, local mass mortality within the Kasimlarceltites fauna due to oxygen fluctuations or methane degassing may have initially led to a primary accumulation. These deposits were then reworked and redeposited basinward by gravity flows to create the present‐day secondary allochthonous concentrations.  相似文献   

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