Is the “Genyornis” egg of a mihirung or another extinct bird from the Australian dreamtime?

© 2016. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/. Following 24 month embargo from date of publication (Feb 1 2016)The iconic Australian Genyornis newtoni (Dromornithidae, Aves) is the sole Pleistocene member of an avian clade now hypothesized to be alternatively in Anseriformes or the sister group of crown Galloanseres. A distinctive type of fossil eggshell commonly found in eroding sand dunes, has been referred to Genyornis newtoni since the 1980s. The 126 by 97 mm Spooner Egg, dated at 54.7 ± 3.1 ka by optical dating of its enclosing sediments, is a complete specimen of this eggshell type that was reconstructed from fragments of a broken egg. We show that the size of the eggs from which this ‘Genyornis’ eggshell derives, either as predicted from measurements of fragments, or as indicated by the Spooner Egg, is unexpectedly small given the size of G. newtoni, which has an estimated mass of 275 kg, or about seven times the mass of the emu that has a similar sized egg. We compared the microstructure of the putative Genyornis eggshell to that of other dromornithids and a range of galloanseriform taxa using several microcharacterisation techniques. The ‘Genyornis’ eggshell displays a mosaic of oological characters that do not unambiguously support referral to any known modern bird. Its shell structure, coupled with chemical compounds in the accessory layer, makes it unlikely to have been laid by a dromornithid, whereas several characters support a megapode origin. A potential candidate for the bird that laid the putative ‘Genyornis’ eggs in the Pleistocene fossil avifaunal record has been ignored: Progura, a genus of extinct giant megapodes, whose species were widespread in Australia. Regression of egg size of megapodes and body mass shows that the Spooner Egg approximates the expected size for eggs laid by species of Progura. We advance the suggestion that the fossil eggshell hitherto referred to Genyornis newtoni, is more likely to have been laid by species of the giant extinct Progura. As megapodes, the species of Progura were obligate ectothermic incubators, which we suggest laid their eggs into a hole dug in sand like the modern megapode Macrocephalon maleo, thus explaining the abundant ‘Genyornis’ eggshell in sand dunes. Referral of this eggshell to Progura means that the fossil record of Genyornis newtoni is limited to bones and the timing of the extinction of this last dromornithid is unknown. In addition, structural similarities of eggshell in megapodes, the putative Genyornis eggshell and dromornithids, raise the possibility that these taxa are phylogenetically more closely related to each other than any is to anseriforms. Specifically, this means that dromornithids might be a sister group to galliforms rather than to or within anseriforms

First Evidence of Reproductive Adaptation to “Island Effect” of a Dwarf Cretaceous Romanian Titanosaur, with Embryonic Integument In Ovo

<div><h3>Background</h3><p>The Cretaceous vertebrate assemblages of Romania are famous for geographically endemic dwarfed dinosaur taxa. We report the first complete egg clutches of a dwarf lithostrotian titanosaur, from Toteşti, Romania, and its reproductive adaptation to the “island effect”.</p> <h3>Methodology/Findings</h3><p>The egg clutches were discovered in sequential sedimentary layers of the Maastrichtian Sânpetru Formation, Toteşti. The occurrence of 11 homogenous clutches in successive strata suggests philopatry by the same dinosaur species, which laid clutches averaging four ∼12 cm diameters eggs. The eggs and eggshells display numerous characters shared with the positively identified material from egg-bearing level 4 of the Auca Mahuevo (Patagonia, Argentina) nemegtosaurid lithostrotian nesting site. Microscopic embryonic integument with bacterial evidences was recovered in one egg. The millimeter-size embryonic integument displays micron size dermal papillae implying an early embryological stage at the time of death, likely corresponding to early organogenesis before the skeleton formation.</p> <h3>Conclusions/Significance</h3><p>The shared oological characters between the Haţeg specimens and their mainland relatives suggest a highly conservative reproductive template, while the nest decrease in egg numbers per clutch may reflect an adaptive trait to a smaller body size due to the “island effect”. The combined presence of the lithostrotian egg and its embryo in the Early Cretaceous Gobi coupled with the oological similarities between the Haţeg and Auca Mahuevo oological material evidence that several titanosaur species migrated from Gondwana through the Haţeg Island before or during the Aptian/Albian. It also suggests that this island might have had episodic land bridges with the rest of the European archipelago and Asia deep into the Cretaceous.</p> </div

Cancer-selective, single agent chemoradiosensitising gold nanoparticles

Two nanometre gold nanoparticles (AuNPs), bearing sugar moieties and/or thiol-polyethylene glycol-amine (PEG-amine), were synthesised and evaluated for their in vitro toxicity and ability to radiosensitise cells with 220 kV and 6 MV X-rays, using four cell lines representing normal and cancerous skin and breast tissues. Acute 3 h exposure of cells to AuNPs, bearing PEG-amine only or a 50:50 ratio of alpha-galactose derivative and PEG-amine resulted in selective uptake and toxicity towards cancer cells at unprecedentedly low nanomolar concentrations. Chemotoxicity was prevented by co-administration of N-acetyl cysteine antioxidant, or partially prevented by the caspase inhibitor Z-VAD-FMK. In addition to their intrinsic cancer-selective chemotoxicity, these AuNPs acted as radiosensitisers in combination with 220 kV or 6 MV X-rays. The ability of AuNPs bearing simple ligands to act as cancer-selective chemoradiosensitisers at low concentrations is a novel discovery that holds great promise in developing low-cost cancer nanotherapeutics

Isotopic ordering in eggshells reflects body temperatures and suggests differing thermophysiology in two Cretaceous dinosaurs

Our understanding of the evolutionary transitions leading to the modern endothermic state of birds and mammals is incomplete, partly because tools available to study the thermophysiology of extinct vertebrates are limited. Here we show that clumped isotope analysis of eggshells can be used to determine body temperatures of females during periods of ovulation. Late Cretaceous titanosaurid eggshells yield temperatures similar to large modern endotherms. In contrast, oviraptorid eggshells yield temperatures lower than most modern endotherms but ~6 °C higher than co-occurring abiogenic carbonates, implying that this taxon did not have thermoregulation comparable to modern birds, but was able to elevate its body temperature above environmental temperatures. Therefore, we observe no strong evidence for end-member ectothermy or endothermy in the species examined. Body temperatures for these two species indicate that variable thermoregulation likely existed among the non-avian dinosaurs and that not all dinosaurs had body temperatures in the range of that seen in modern birds

Cuidados veterinários e infeção parasitária em animais de companhia seguidos numa clínica médico-veterinária

O objetivo deste trabalho foi determinar as espécies animais que frequentam uma clínica médico-veterinária, os cuidados que os proprietários têm, os problemas mais frequentes e quais os métodos de prevenção utilizados. Pretendeu-se ainda avaliar a fauna parasitária presente em felídeos e canídeos seguidos na clínica. Em 2011, acompanharam-se 133 casos clínicos e realizaram-se 113 inquéritos a donos de animais. Efetuaram-se recolhas de fezes, num total de 86 amostras, que foram sujeitas a análises coprológicas qualitativas pela técnica de Willis. Os cães com idades entre >18 meses-6 anos, do sexo feminino, de raça pura, com porte pequeno e pelagem curta foram predominantes. Os felídeos com idade entre >18 meses-6 anos, do sexo feminino, pelagem curta e de raça indeterminada dominaram. Prevaleceram as consultas de rotina e nestas as relacionadas com a sanidade. As patologias predominantes foram do foro digestivo, urinário e dermatológico. Em cirurgia salientaram-se as esterilizações. Oito dos canídeos apresentaram ovos de Ascarididae, Ancylostomatidae e Trichuridae. Ctenocephalides felis felis, Ixodes ventalloi e R. sanguineus identificaram-se num gato e em três cães.Verificou-se que cada vez mais os proprietários têm consciência da importância do bem-estar e saúde animal como forma de proteger a sua própria saúde, levando os animais ao médico-veterinário. This study aimed to identify the more frequent pets that attend a veterinary clinic, the owners care, the main issues affecting pets, and the followed preventive measures. Simultaneously, a parasitological evaluation was performed in felines and canines attending the clinic. In 2011, 133 clinical cases were followed up and 113 enquiries performed to animal owners. Faeces were collected on pets examined in the clinic, with a total of 86 samples. Qualitative parasitological fecal analyses were performed. Dogs, aged between> 18m-6a, female, purebreds, small size and short pelage were predominant. Relatively to the cats, prevailed age between> 18m-6a, female sex, indeterminate race and short pelage. Routine visits prevailed and inside this, the appointments for sanitary issues were superior. The most frequent pathologies observed were related to the digestive and urinary systems and skin. In surgery, sterilizations were more frequent. In 8 dog faeces Ascarididae, Ancylostomatidae and Trichuridae eggs were identified. Ctenocephalides felis felis and Ixodes ventalloi and R. sanguineus were identified in three dogs and one cat. This study emphasized that owners are aware of animal welfare and animal health as a way of protection of their own health, and use to take their pets more often to a vet

A comparison of the radiosensitisation ability of 22 different element metal oxide nanoparticles using clinical megavoltage X-rays

Background: A wide range of nanoparticles (NPs), composed of different elements and their compounds, are being developed by several groups as possible radiosensitisers, with some already in clinical trials. However, no systematic experimental survey of the clinical X-ray radiosensitising potential of different element nanoparticles has been made. Here, we directly compare the irradiation-induced (10 Gy of 6-MV X-ray photon) production of hydroxyl radicals, superoxide anion radicals and singlet oxygen in aqueous solutions of the following metal oxide nanoparticles: Al2O3, SiO2, Sc2O3, TiO2, V2O5, Cr2O3, MnO2, Fe3O4, CoO, NiO, CuO, ZnO, ZrO2, MoO3, Nd2O3, Sm2O3, Eu2O3, Gd2O3, Tb4O7, Dy2O3, Er2O3 and HfO2. We also examine DNA damage due to these NPs in unirradiated and irradiated conditions. Results: Without any X-rays, several NPs produced more radicals than water alone. Thus, V2O5 NPs produced around 5-times more hydroxyl radicals and superoxide radicals. MnO2 NPs produced around 10-times more superoxide anions and Tb4O7 produced around 3-times more singlet oxygen. Lanthanides produce fewer hydroxyl radicals than water. Following irradiation, V2O5 NPs produced nearly 10-times more hydroxyl radicals than water. Changes in radical concentrations were determined by subtracting unirradiated values from irradiated values. These were then compared with irradiation-induced changes in water only. Irradiation-specific increases in hydroxyl radical were seen with most NPs, but these were only significantly above the values of water for V2O5, while the Lanthanides showed irradiation-specific decreases in hydroxyl radical, compared to water. Only TiO2 showed a trend of irradiation-specific increase in superoxides, while V2O5, MnO2, CoO, CuO, MoO3 and Tb4O7 all demonstrated significant irradiation-specific decreases in superoxide, compared to water. No irradiation-specific increases in singlet oxygen were seen, but V2O5, NiO, CuO, MoO3 and the lanthanides demonstrated irradiation-specific decreases in singlet oxygen, compared to water. MoO3 and CuO produced DNA damage in the absence of radiation, while the highest irradiation-specific DNA damage was observed with CuO. In contrast, MnO2, Fe3O4 and CoO were slightly protective against irradiation-induced DNA damage. Conclusions: Beyond identifying promising metal oxide NP radiosensitisers and radioprotectors, our broad comparisons reveal unexpected differences that suggest the surface chemistry of NP radiosensitisers is an important criterion for their success

Paleobiology of titanosaurs: reproduction, development, histology, pneumaticity, locomotion and neuroanatomy from the South American fossil record

Fil: García, Rodolfo A.. Instituto de Investigación en Paleobiología y Geología. Museo Provincial Carlos Ameghino. Cipolletti; ArgentinaFil: Salgado, Leonardo. Instituto de Investigación en Paleobiología y Geología. General Roca. Río Negro; ArgentinaFil: Fernández, Mariela. Inibioma-Centro Regional Universitario Bariloche. Bariloche. Río Negro; ArgentinaFil: Cerda, Ignacio A.. Instituto de Investigación en Paleobiología y Geología. Museo Provincial Carlos Ameghino. Cipolletti; ArgentinaFil: Carabajal, Ariana Paulina. Museo Carmen Funes. Plaza Huincul. Neuquén; ArgentinaFil: Otero, Alejandro. Museo de La Plata. Universidad Nacional de La Plata; ArgentinaFil: Coria, Rodolfo A.. Instituto de Paleobiología y Geología. Universidad Nacional de Río Negro. Neuquén; ArgentinaFil: Fiorelli, Lucas E.. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica. Anillaco. La Rioja; Argentin