Stratigraphic analysis of a fossil Neogoniolithon-capped patch reef and associated facies,San Salvador,Bahamas

An unusual Pleistocene patch reef is exposed in a coastal cliff at Grotto Beach, San Salvador, Bahamas. The reef is a coralline framestone constructed mainly by Porites astreoides together with a few large heads of Diploria strigosa and Montastrea annularis, and is capped by a dense thicket of Neogoniolithon strictum that is interpreted as marking the subtidal/intertidal boundary. The reef is flanked to the northeast by laminated to low-angle cross-laminated intraclastic grainstones and to the southwest by skeletal rudstone of reefal and interreefal derivation. Uranium-series dating of pure aragonite from a Diploria corallum yielded an age of 123 000±9000 years. Reef growth began on an erosional surface underlain by steeply crossbedded eolian grainstone. As the reef grew upward, it also grew laterally over adjacent penecontemporaneous subtidal sediments. The reef was eventually buried by 2.3 m of shallow subtidal and beach sediments that apparently prograded seaward during a highstand, or possibly while sea level was still rising. The shallow subtidal sediments are mainly peloidal, ooidal and skeletal grainstones that are pervasively bioturbated. The overlying beach facies comprises predominantly laminated, sparsely burrowed grainstone. The beach and shallow subtidal facies contain boulders of fine-grained laminated grainstone that are interpreted as storm-tossed blocks of beachrock. Living analogs of the Grotto Beach fossil reef lie off East Beach, San Salvador. Several of these have a flourishing cap of Neogoniolithon that extends above low-tide level and we believe that the Neogoniolithon cap of Grotto Beach reef did likewise. Wherever found in the stratigraphic record this facies should serve to identify the subtidal/intertidal boundary. The uppermost Pleistocene beach sediments associated with Grotto Beach fossil reef lie 5.8 m above present-day mean sea level, which ist strong evidence that this portion of San Salvador has undergone little subsidence since the Grotto Beach section was deposited.     

Dental Ontogeny in Pliocene and Early Pleistocene Hominins

Until recently, our understanding of the evolution of human growth and development derived from studies of fossil juveniles that employed extant populations for both age determination and comparison. This circular approach has led to considerable debate about the human-like and ape-like affinities of fossil hominins. Teeth are invaluable for understanding maturation as age at death can be directly assessed from dental microstructure, and dental development has been shown to correlate with life history across primates broadly. We employ non-destructive synchrotron imaging to characterize incremental development, molar emergence, and age at death in more than 20 Australopithecus anamensis, Australopithecus africanus, Paranthropus robustus and South African early Homo juveniles. Long-period line periodicities range from at least 6–12 days (possibly 5–13 days), and do not support the hypothesis that australopiths have lower mean values than extant or fossil Homo. Crown formation times of australopith and early Homo postcanine teeth fall below or at the low end of extant human values; Paranthropus robustus dentitions have the shortest formation times. Pliocene and early Pleistocene hominins show remarkable variation, and previous reports of age at death that employ a narrow range of estimated long-period line periodicities, cuspal enamel thicknesses, or initiation ages are likely to be in error. New chronological ages for SK 62 and StW 151 are several months younger than previous histological estimates, while Sts 24 is more than one year older. Extant human standards overestimate age at death in hominins predating Homo sapiens, and should not be applied to other fossil taxa. We urge caution when inferring life history as aspects of dental development in Pliocene and early Pleistocene fossils are distinct from modern humans and African apes, and recent work has challenged the predictive power of primate-wide associations between hominoid first molar emergence and certain life history variables.     

26Al/10Be Burial Dating of Xujiayao-Houjiayao Site in Nihewan Basin,Northern China

The Xujiayao-Houjiayao site in Nihewan Basin is among the most important Paleolithic sites in China for having provided a rich collection of hominin and mammalian fossils and lithic artifacts. Based on biostratigraphical correlation and exploratory results from a variety of dating methods, the site has been widely accepted as early Upper Pleistocene in time. However, more recent paleomagnetic analyses assigned a much older age of ∼500 ka (thousand years). This paper reports the application of ²⁶Al/¹⁰Be burial dating as an independent check. Two quartz samples from a lower cultural horizon give a weighted mean age of 0.24 ± 0.05 Ma (million years, 1σ). The site is thus younger than 340 ka at 95% confidence, which is at variance with the previous paleomagnetic results. On the other hand, our result suggests an age of older than 140 ka for the site’s lower cultural deposits, which is consistent with recent post-infrared infrared stimulated luminescence (pIR-IRSL) dating at 160–220 ka.     

Late Quaternary Palaeoichnological Sites from the Southern Atlantic Coast of Buenos Aires Province,Argentina: Mammal,Bird and Hominid Evidence

Palaeontological and palaeoichnological studies were made along the southeastern coast of Buenos Aires province, Argentina. Continental Late Pleistocene and continental, transitional and marine Holocene stratigraphic units were identified. The former are represented by fossil mammal bones and ichnites dated from 16,000 to 12,000 y. B.P. Continental Early Holocene beds dated circa 8,100 years B.P. contain fish, rodent and bird remains. Middle Holocene sediments 6,930 to 6,570 years B.P. are recorded by deposits bioturbated by estuarine crabs. During the Late Holocene, between 5,000 and 4,800 B.P., a marine transgression is recorded by a very rich mollusc fauna. The palaeoenvironmental variety recorded along a few tens of kilometers of the coast is a distinctive feature of this part of the Argentine coastal region. At Monte Hermoso beach, in the eastern part of the studied zone, archaeological materials were dated 7,300 years B.P., and human footprints dated 7,125 years B.P. were also recorded. In January 2005 some isolated human footprints were found at Pehuen-Co palaeoichnological site, which are older than those found at Monte Hermoso beach and of the same age as the oldest human archaeological findings in Patagonia, that is about 12,000 yeas B.P.     

A Middle Pleistocene Sea Otter from Northern California and the Antiquity of <Emphasis Type="Italic">Enhydra</Emphasis> in the Pacific Basin

Extant sea otters (Enhydra lutris) are remarkably well understood in terms of behavior, ecology, and interactions with humans, but the evolutionary history of this charismatic marine mammal is limited owing to a fragmentary fossil record. Disagreements over the generic assignment of various fossil otter remains to members of the tribe Enhydrini, and limited geochronologic data for these records have impeded attempts to interpret the evolutionary biogeography of Enhydra. A well-preserved femur of Enhydra sp. from a middle Pleistocene horizon within the Merced Formation of northern California is the oldest record of Enhydra in the Pacific with robust geochronologic age control. Bracketing ⁸⁷Sr/⁸⁶Sr dates indicate an age of 620–670 ka. Reappraisal of the geochronologic age of various occurrences of Enhydrini indicate dispersal of Enhydra into the Pacific through the Bering Strait no earlier than the middle Pleistocene. Somewhat older early Pleistocene fossils of Enhydra from Alaska and England suggest an Arctic or North Atlantic origin of the Enhydra lineage.     

The last terror birds (Aves,Phorusrhacidae): new evidence from the late Pleistocene of Uruguay

We report new fossil evidence of terror bird survival until the end of the Pleistocene in Uruguay. The new specimens comprise the distal portion of right tarsometatarsus and a left humerus; the latter is assigned to the genus Psilopterus. The sedimentary context of the remains yields a characteristic Pleistocene mammalian association along with numerical age dating giving an undoubted late Pleistocene age (OSL 96,040 ± 6300 years). We also revise and discuss the systematic placement of late Pleistocene phorusrhacid material previously published. The trophic role of terror birds and other South American carnivorous birds in late Pleistocene ecosystems should be revised based on the increasing findings of avian fossil materials.     

Plio-Pleistocene Carnivora of northwestern Africa: A short review

The fossil record of northwestern African carnivores is very patchy. The richest assemblage is that of the Late Pliocene of Ahl al Oughlam, with more than 20 species belonging to the main modern families. Some additions to its study are made here. The rather poor Early Pleistocene faunas are mainly marked by the arrival of a large Canis. A fauna of modern type, with example, the duo Hyaena–Crocuta, settles in the Earliest Pleistocene site of Tighenif, where some older elements linger on (Homotherium), beside some taxa of doubtful affinities, like a large Panthera, and a strange canid close to Nyctereutes, dominant at this site as well as at the slightly younger ones of Thomas and Oulad Hamida Quarries in Casablanca. All these faunas consist mostly of African taxa, together with a Palaearctic component whose importance increases towards the end of the Pleistocene.     

Bioerosive structures from Miocene marine mobile‐substrate communities in southern Spain,and description of a new sponge boring

Abstract: Neogene palaeoshore sediments are abundantly represented along the Mediterranean coast of Iberia. An outcrop north of the Sierra Tejeda, named La Resinera, exposes concentrations of pebbles and boulders of marble, comprising an upper Miocene marine beach deposit. The high diversity of bioerosion trace fossils present in these boulders includes structures produced by polychaete annelids, demosponges, echinoids and endolithic bivalves, which indicate a shallow shoreface environment. The ichnotaxa represented are Maeandropolydora sulcans, Caulostrepsis taeniola, Entobia geometrica, Entobia ovula, Circolites kotoncensis, Gastrochaenolites torpedo, Gastrochaenolites lapidicus, Gastrochaenolites ornatus and Gastrochaenolites turbinatus. The borings are Tortonian (late Miocene) in age. Also present, and particularly abundant, are large sponge borings that have a single chamber from which radiating canals emerge. This trace fossil is designated as Entobia resinensis isp. nov.     

Preliminary study of the calcareous taphocoenoses in Late Quaternary glacial marine sequences of the Ross Sea (Antarctica)

Three gravity cores were collected in north-western Ross Sea (Coulman Island and Cape Adare areas) during 1998 and 1999 “Progetto Nazionale Ricerche in Antartide”. Several carbonate-rich levels, from Late Pleistocene to Holocene in age, interbedded with glacial marine sequences were recovered. Examination of the compositional characters (X-ray structure, texture, water, TOC and CaCO₃ contents) and taphonomic data (fabric of the fossil concentration, degree of preservation of foraminifers and bryozoans, together with paleoecological inferences) has allowed the preliminary documentation of oscillations of the ice-shelf front in this area. Benthic foraminifer tests in glacial marine sediments older than the Last Glacial Maximum are often badly preserved (abraded and broken), testifying to the persistent transport of these sediments. In the younger sediments, an increased concentration of Neogloboquadrina pachyderma occurs, indicating more open water conditions. The occurrence of a mainly autochthonous fauna in muddy sediments in between two volcanic events in the Coulman Island area could indicate stable environmental conditions. The occurrence of limited % of fragmented foraminifers indicates the decreasing influence of glacial reworking. In the Cape Adare area, mass flow events were common during the Holocene retreat of the ice shelf. Several bioclastic-rich deposits (stylasterids and bryozoans assemblage) in the studied core with interbedded muddy sediments could indicate mass transport events from neighboring shallow environments. During undisturbed open-marine conditions, represented by muddy sedimentation, foraminifers and other calcareous taxa colonized the previous coarse-textured skeletal substratum.     

New material of Pleistocene cats (Carnivora, Felidae) from Southern South America, with comments on biogeography and the fossil record

In this paper the systematic position and age of several Pleistocene cat remains found in southern South American are studied, in an attempt to more fully document the scarce record of the group and clear up their obscure Quaternary history. The fossils are compared with a large sample of recent specimens by means of qualitative and quantitative characters, as well as multivariate methods (discriminant analysis). The age of previous records is restricted using recent chronostratigraphic and biostratigraphic studies. Ly. colocolo is recorded in the late Ensenadan (0.78-0.5 Ma BP) and Bonaerian/Lujanian (0.5 Ma-8.5 Ka BP) ages of the Pampean Region (Argentina) and in the late Pleistocene or Holocene of Tierra del Fuego (Chile). An incomplete hemimandible found in the Bonaerian of the Pampean Region is referred to cf. Herpailurus and could be the earliest record of this lineage. Two other remains could belong to On. geoffroyi, but their incompleteness and some differences prevent their assignation to this recent species. The age of “Felis” vorohuensis is restricted to the late Ensenadan. The fossil record of the Ocelot Lineage is very fragmentary, but it is at least as old as late Ensenadan. Taphonomic biases are responsible for this poor fossil record and this fact could partially explain the hiatus with respect to the timing estimated by molecular divergence. The combination of data suggests that Ly. colocolo, On. guigna, On. geoffroyi and Oreailurus jacobita speciated in South America, supporting previous opinions. If the molecular divergence dates are right the recent diversity of this group could be explained by a minimum of five to six immigrations.     

Conclusion. Bilan des recherches interdisciplinaires effectuées sur le site de l’Homo erectus de Denizli,Kocabaş, Bassin de Denizli,Anatolie, Turquie. L’Homo erectus aux portes de l’Europe

The study of the site of Kocaba?, which yielded an archaic Homo erectus skullcap, was undertaken in 2011 and 2012, at the request of Professor Mehmet Cihat Alçiçek. This interdisciplinary French–Turkish research programme comprised the geochronological, magnetostratigraphic, biochronological and paleoenvironmental study of the site and the paleoanthropological study of the skullcap itself. The association of large mammals enabled us to attribute the travertine formations bearing the skullcap to the second part of the Upper Pleistocene, and more specifically to between 1.5 and 1.2 million years, because of the disappearance or appearance of certain species. This biochronological age is confirmed by the paleomagnetism study, which places the travertines bearing the skullcap in a period of reversed polarity, underlying a normal polarity formation, which could be attributed to the Cobb Mountain paleomagnetic excursion, dated to 1,194,000 years. The dating of these fauna by the ²⁶Al/¹⁰Be cosmogenic nuclide method by Anne-Elisabeth Lebatard yielded an age older than 1.22 Ma and more recent than 1.5 Ma. The Hominid skullcap from this formation can be attributed to a Homo erectus, slightly more evolved than those of Homo ergaster KNM-ER 3733 (1.78 Ma) and KNM-ER 15,000 (1.5 Ma), similar to that of Daka (Bouri), which is about a million years old and older than the Bodo fossil (estimated at 600,000 years) and Kabwe (between 300,000 and120,000 years). The archaic Homo erectus skullcap from Kocaba?, referred to as Denizli Man, proves that Homo erectus was already present in Anatolia, at the crossroads of Africa, Asia and Europe, a little more than 1.2 million years ago.     

Fossil blackflies from Pleistocene interglacial deposits in Norfolk, England (Diptera: Simuliidae)

ABSTRACT. The occurrence is reported of fragmentary simuliids among Pleistocene fossil arthropod assemblages recovered from deposits in Norfolk of Ipswichian (last) interglacial age, 130 000–120 000 years BP. The condition of each of the nineteen available specimens is described, and sixteen of them are photographically illustrated. Specimens are identified as Simulium s. l. but reliable identification beyond generic level is precluded by lack of diagnostic taxonomic characters. The palaeoenviron-mental significance of simuliids in Quaternary fossil assemblages is briefly discussed; it is thought that the simuliids indicate a palaeoclimate no colder, and possibly warmer, than today.     

Pleistocene Calabrian and Sicilian bioprovinces

During the Pleistocene, southern Calabria was the area through which several mammalian taxa dispersed into the Sicilian island via the Straits of Messina. The rich fossil record of Sicily allowed for the construction of a fairly detailed bio-chronological frame that is dated by correlation of vertebrate bearing deposits with marine deposits. At present five Faunal Complexes (F.C.), characterised by the occurrence of different taxa, have been recognised. The two older Faunal Complexes (Monte Pellegrino F.C.'xes Elephas falconeri F.C.) include taxa with differently marked endemic features denoting the occurrence of an insular system made up of geographically isolated small islands, with very difficult and sporadic connections with the mainland. The Lower Pleistocene physiographic evidence fits closely with data coming from palaeontologic evidence. In the younger F.C.'xes (E. mnaidriensis F.C., Pianetti S. Teodoro F.C. and Castello F.C.), faunal composition is becoming more similar to that of the southern Italian peninsula, endemisation is more moderate becoming absent in the youngest assemblages. This behaviour denotes that temporary connections with southern Italy occurred more frequently and extensively during Late Middle Pleistocene and Late Pleistocene. Possibly a sort of filtering barrier affected the dispersals that gave rise to the former phase of population of the E. mnaidriensis F.C. preventing small mammals from the mainland from entering the island. The vertebrate fossil record of southern Calabria is rather poor and no mammal deposit is apparently older than the Late Middle Pleistocene. The occurrence at Bovetto of a continental fallow deer (Dama dama cf. tiberina), closely related to the endemic Sicilian species D. carburangelensis of the E. mnaidriensis F.C., may document the first Pleistocene connection of southern Calabria to the Italian peninsula and the dispersal of the forerunners of mammals of the E. mnaidriensis F.C. in Sicily. The well-diversified continental faunas coming from Archi and from Iannì di S. Calogero, both containing remains of Homo sapiens neanderthalensis, may document a post-Tyrrhenian dispersal event through the Catanzaro isthmus. Data are still lacking for the correlation of these faunal assemblages with the scarcely endemic faunas of the Late Pleistocene Contrada Pianetti–San Teodoro F.C. of Sicily. No record of the mammal assemblages that gave origin to the fauna of the Castello F.C. has been recovered so far in southern Calabria.     

关于萨拉乌苏遗址地层及人类化石年代的问题

本文回顾了与人类化石相关的萨拉乌苏河晚更新世地层及文化层的年代学研究,经过14C测年和相关证据认为,采集的萨拉乌苏PA.62号股骨不属于萨拉乌苏遗址的原生地层。     

The Pleistocene deer hunter of Sardinia

The Pleistocene mammalian fauna of Sardinia isendemic and consists of only a few taxa, indicating island conditions at the time.A sharp faunal break in the Middle Pleistocene separates an older fauna with Nesogoral from a younger one (Middle/Upper Pleistocene) which contains mainly deer (Megaceros cazioti), and ochotonid (Prolagus sardus), a small canid (Cynotherium sardous), and Tyrrhenicola.Commonly paleoecological conditions on islands have led to the development of faunas with dwarfed species, showing a low gear locomotion due to lack of large carnivores. In this aspect the younger Pleistocene fauna of Sardinia is different. A deer with the proportion of mainland species and a small canid were found. This is suggestive of the presence of a large predator. Indeed, together with this fauna a human temporal bone, showing some distinctive characters, was found in Grotta di Corbeddu, Oliena, Sardinia.These findings gave rise to further excavations in the same cave. A paleolithic settlement was discovered and two types of bone artefact could be distinguished. ¹⁴C dating revealed an age of 13590±140 yrs. B.P.These results suggest the development of an endemichuman culture, adapted to the restricted island environment and to the monotonous prey of deer and ochotonids, different from any known culture of that age.     

Determination of paleoseasonality of fossil brachiopods using shell spiral deviations and chemical proxies

Brachiopods have been extensively used in paleoclimatic and paleoecological reconstructions, but their utility would greatly increase if paleoseasonality information could be obtained from their shells. Determining seasonal seawater temperature variations from fossil brachiopods requires knowledge of specimen ontogenetic ages, which is difficult to determine compared to other organisms secreting a shell by accretion. In this study, the combination of the spiral deviation methodology and chemical proxies is tested for determining specimen ontogenetic ages and paleoseasonality using two species of fossil brachiopods, Laqueus rubellus and Terebratula terebratula, of Pleistocene and Late Miocene age, respectively. Spiral deviations were obtained for Laqueus and Terebratula using an R program developed for modern taxa, and well-preserved shells were analyzed using oxygen isotopes and Mg/Ca ratios as chemical proxies for past seawater temperature. Results reveal that locations of spiral deviations on shells of L. rubellus displayed a strong direct relationship with Mg concentrations, and resulting Mg/Ca-derived paleotemperatures were seasonal. Conversely, specimens of T. terebratula did not show a consistently strong relationship between Mg concentrations and spiral deviations, although resulting paleotemperatures agreed with those from previous studies. Overall, the results from this study indicate that the spiral deviation methodology combined with chemical proxies presents great potential for utility in past seasonal seawater temperature reconstructions in pristinely preserved, biconvex fossil brachiopods.     

Calibrated chronograms,fossils, outgroup relationships,and root priors: re‐examining the historical biogeography of Geraniales

We re‐examined the recent study by Palazzesi et al., (2012) published in the Biological Journal of the Linnean Society (107: 67–85), that presented the historical diversification of Geraniales using BEAST analysis of the plastid spacer trnL–F and of the non‐coding nuclear ribosomal internal transcribed spacers (ITS). Their study presented a set of new fossils within the order, generated a chronogram for Geraniales and other rosid orders using fossil‐based priors on five nodes, demonstrated an Eocene radiation of Geraniales (and other rosid orders), and argued for more recent (Pliocene–Pleistocene) and climate‐linked diversification of genera in the five recognized families relative to previous studies. As a result of very young ages for the crown of Geraniales and other rosid orders, unusual relationships of Geraniales to other rosids, and apparent nucleotide substitution saturation of the two gene regions, we conducted a broad series of BEAST analyses that incorporated additional rosid fossil priors, used more accepted rosid ordinal topologies, or altered the placement of one fossil Geraniales prior. Our results indicate that their ages are 20–50% too young owing to a combination of (1) strong nucleotide saturation of the DNA regions starting at 65 Mya, (2) lack of a root (rosid stem) or other rosid ordinal stem fossil‐based priors, (3) the inability of the two DNA regions (with alignment issues) to obtain a monophyletic Geraniales as well as reasonable relationships of Geraniales to other rosid orders, and (4) apparent issues with the nodal placement of a Pelargonium fossil. The Geraniales crown is much older (Campanian of the Cretaceous; 86 Mya), the posterior age distribution on all but two fossil nodes are well older than the priors, the placement of a Pelargonium‐like fossil is more likely at the crown rather than the stem, but their models of diversification within several clades linked to climatic and orogeny appear supported. We discuss a number of the inherent issues of relaxed‐clock dating and outline some ‘best practice’ approaches for such studies. © 2014 The Linnean Society of London, Biological Journal of the Linnean Society, 2014, 113 , 29–49.     

New data on the origin of Nesiotites (Soricidae,Mammalia) in Menorca (Balearic Islands,Spain)

The presence of the shrew Nesiotites in Menorca is not yet adequately explained. Some authors consider that its ancestor arrived during the Messinian Salinity Crisis, as happened in Mallorca. Other authors consider that fossil populations in Menorca are the result of a later migration from Mallorca. In this work, several biometrical and morphological characters of abundant fossil populations from both islands have been studied. The results indicate that Early Pleistocene populations in Mallorca and Menorca are rather indistinguishable. Therefore, an early post-Messinian (Pliocene) isolation of Nesiotites in both islands is quite unlikely.     

Polyamine metabolism of potato seed-tubers during long-term storage and early sprout development

Growth potential of potato (Solanum tuberosum L.) plants is influenced by seed-tuber age. After 24 days of growth, single-eye seedcores from 7-month-old seed-tubers produced 64% more foliar dry matter than those from 19-month-old seed-tubers, reflecting a higher growth rate. This study was initiated to determine if differences in polyamine (PA) metabolism are associated with aging and age-reduced vigor of potato seed-tubers. As tubers aged in storage, putrescine (Put) increased 2.2-fold, while spermidine (Spd) and spermine (Spm) decreased 33% and 38%, respectively. Ethylene content of the tuber tissue also increased with advancing age, suggesting that during the aging process S-adenosylmethionine was directed toward ethylene biosynthesis at the expense of the PAs. Single-eye cores from 7- and 19-month-old tubers were sown and PA levels in core and shoot tissues were monitored during plant development. Put titer of younger cores increased 8.8-fold by 12 days. In contrast, the increase in Put over the initial titer in older cores was 2.9-fold. The reduced ability of older cores to synthesize Put during plant establishment is probably due to a 45% decline in ornithine decarboxylase activity between 12 and 16 days after planting. Lack of available Put substrate limited the biosynthesis of Spd and Spm, and thus their concentrations remained lower in older cores than in younger cores. Lower PA titer in older cores during plant establishment is thus coincident with reduced growth potential. Concentrations of Put and Spd were higher in shoots developing from older cores throughout the study, but there was no age-related difference in Spm content. In contrast, activities of arginine and S-adenosylmethionine decarboxylases were higher in shoots from younger cores during establishment. The results indicate that aging affects PA metabolism in both tuber and developing plant tissues, and this may relate to loss of growth potential with advancing seed-tuber age.