Diversification dynamics of a common deep-sea octocoral family linked to the Paleocene-Eocene thermal maximum

The deep-sea has experienced dramatic changes in physical and chemical variables in the geological past. However, little is known about how deep-sea species richness responded to such changes over time and space. Here, we studied the diversification dynamics of one of the most diverse octocorallian families inhabiting deep sea benthonic environments worldwide and sustaining highly diverse ecosystems, Primnoidae. A newly dated species-level phylogeny was constructed to infer their ancestral geographic locations and dispersal rates initially. Then, we tested whether their global and regional (the Southern Ocean) diversification dynamics were mediated by dispersal rate and abiotic factors as changes in ocean geochemistry. Finally, we tested whether primnoids showed changes in speciation and extinction at discrete time points. Our results suggested primnoids likely originated in the southwestern Pacific Ocean during the Lower Cretaceous ∼112 Ma, with further dispersal after the physical separation of continental landmasses along the late Mesozoic and Cenozoic. Only the speciation rate of the Southern Ocean primnoids showed a significant correlation to ocean chemistry. Moreover, the Paleocene-Eocene thermal maximum marked a significant increase in the diversification of primnoids at global and regional scales. Our results provide new perspectives on the macroevolutionary and biogeographic patterns of an ecologically important benthic organism typically found in deep-sea environments.

A new Mourasuchus (Alligatoroidea, Caimaninae) from the late Miocene of Venezuela, the phylogeny of Caimaninae and considerations on the feeding habits of Mourasuchus

Mourasuchus (Alligatoroidea, Caimaninae) is one of the most peculiar crocodyliforms due to the skull morphology consisting of a long, wide, dorsoventrally flat rostrum with long, slender mandibular rami. Despite these peculiarities, the systematics, phylogeny and feeding habits of this taxon have not been properly studied. In this paper, we describe a new species of the genus, Mourasuchus pattersoni sp. nov., from the late Miocene of the Urumaco Formation of Venezuela. The new species differs from the other Mourasuchus species in having a lateromedially wide, dorsoventrally high jugal bone and a circular incisive foramen, which both represent autapomorphies of the new taxon. Phylogenetically, M. pattersoni sp. nov. is more closely related to M. amazonensis and the specimen UFAC-1424 (formely attributed to M. nativus) than to M. arendsi or M. atopus, whilst Mourasuchus is recovered once more as a monophyletic group. Furthermore, the cladistic analysis performed in this contribution offers a new phylogenetic assessment of Caimaninae, including many taxa described recently for the group. In this study, we also discuss the crocodylian diversity of the Urumaco Formation as well as how paleoenvironment may have contributed toward its evolution. In addition, we provide a discussion of the potential feeding habits of Mourasuchus. In this contribution, Mourasuchus is regarded as a taxon that likely preferred to prey on small animals. The unusual skull morphology of this group may have evolved to cover a large area with the rostrum, allowing for a more efficient prey capture, while the prey may have consisted predominantly of large amounts of small animals.

The last marine pelomedusoids (Testudines: Pleurodira): a new species of Bairdemys and the paleoecology of Stereogenyina

The extinct Stereogenyina turtles form a relatively diverse Podocnemididae lineage, with twelve described and phylogenetically positioned species. They are characterized by a wide geographic and temporal range, from the Eocene of Africa to the Pleistocene of Southeast Asia, and a peculiar palate morphology, with a secondary palate that is unique among side-necked turtles. Here, we describe a new Stereogenyina species, based on an almost complete skull from the middle Miocene Capadare Formation, of Venezuela. A new phylogenetic analysis supports the assignment of the new species to the genus Bairdemys. Based on geometric morphometrics analyses, we related the development of the stereogenyin secondary palate with the acquisition of a durophagous diet. Based on a review of the sedimentary environments where their fossils are found, we also propose that stereogenyins were a marine radiation of podocnemidid turtles, as corroborated by previous studies of fossil eggs and limb morphology. These two inferences allowed us to hypothesize that stereogenyins occupied an ecological niche similar to that of the extant Carettini sea turtles, and that the rise of the latter group may be related to the Stereogenyina diversity fall in the end of the Miocene.

Erratum: A new enigmatic Late Miocene mylodontoid sloth from northern South America

[This corrects the article DOI: 10.1098/rsos.140256.].

A new enigmatic Late Miocene mylodontoid sloth from northern South America

A new genus and species of sloth (Eionaletherium tanycnemius gen. et sp. nov.) recently collected from the Late Miocene Urumaco Formation, Venezuela (northern South America) is herein described based on a partial skeleton including associated femora and tibiae. In order to make a preliminary analysis of the phylogenetic affinities of this new sloth we performed a discriminate analysis based on several characters of the femur and tibia of selected Mylodontoidea and Megatherioidea sloths. The consensus tree produced indicates that the new sloth, E. tanycnemius, is a member of the Mylodontoidea. Surprisingly, the new taxon shows some enigmatic features among Neogene mylodontoid sloths, e.g. femur with a robust lesser trochanter that projects medially and the straight distinctly elongated tibia. The discovery of E. tanycnemius increases the diversity of sloths present in the Urumaco sequence to ten taxa. This taxon supports previous studies of the sloth assemblage from the Urumaco sequence as it further indicates that there are several sloth lineages present that are unknown from the better sampled areas of southern South America.

Erratum: Addendum to 'New dinosaur (Theropoda, stem-Averostra) from the earliest Jurassic of the La Quinta formation, Venezuelan Andes'

[This corrects the article DOI: 10.1098/rsos.140184.].

New dinosaur (Theropoda, stem-Averostra) from the earliest Jurassic of the La Quinta formation, Venezuelan Andes

Dinosaur skeletal remains are almost unknown from northern South America. One of the few exceptions comes from a small outcrop in the northernmost extension of the Andes, along the western border of Venezuela, where strata of the La Quinta Formation have yielded the ornithischian Laquintasaura venezuelae and other dinosaur remains. Here, we report isolated bones (ischium and tibia) of a small new theropod, Tachiraptor admirabilis gen. et sp. nov., which differs from all previously known members of the group by an unique suite of features of its tibial articulations. Comparative/phylogenetic studies place the new form as the sister taxon to Averostra, a theropod group that is known primarily from the Middle Jurassic onwards. A new U-Pb zircon date (isotope dilution thermal-ionization mass spectrometry; ID-TIMS method) from the bone bed matrix suggests an earliest Jurassic maximum age for the La Quinta Formation. A dispersal-vicariance analysis suggests that such a stratigraphic gap is more likely to be filled by new records from north and central Pangaea than from southern areas. Indeed, our data show that the sampled summer-wet equatorial belt, which yielded the new taxon, played a pivotal role in theropod evolution across the Triassic-Jurassic boundary.

Functional genomic and serological analysis of the protective immune response resulting from vaccination of macaques with an NS1-truncated influenza virus

We are still inadequately prepared for an influenza pandemic due to the lack of a vaccine effective for subtypes to which the majority of the human population has no prior immunity and which could be produced rapidly in sufficient quantities. There is therefore an urgent need to investigate novel vaccination approaches. Using a combination of genomic and traditional tools, this study compares the protective efficacy in macaques of an intrarespiratory live influenza virus vaccine produced by truncating NS1 in the human influenza A/Texas/36/91 (H1N1) virus with that of a conventional vaccine based on formalin-killed whole virus. After homologous challenge, animals in the live-vaccine group had greatly reduced viral replication and pathology in lungs and reduced upper respiratory inflammation. They also had lesser induction of innate immune pathways in lungs and of interferon-sensitive genes in bronchial epithelium. This postchallenge response contrasted with that shortly after vaccination, when more expression of interferon-sensitive genes was observed in bronchial cells from the live-vaccine group. This suggested induction of a strong innate immune response shortly after vaccination with the NS1-truncated virus, followed by greater maturity of the postchallenge immune response, as demonstrated with robust influenza virus-specific CD4+ T-cell proliferation, immunoglobulin G production, and transcriptional induction of T- and B-cell pathways in lung tissue. In conclusion, a single respiratory tract inoculation with an NS1-truncated influenza virus was effective in protecting nonhuman primates from homologous challenge. This protection was achieved in the absence of significant or long-lasting adverse effects and through induction of a robust adaptive immune response.

[A new species of snake of the genus Sibon (Serpentes: Colubridae) of the Caribbean slope of Costa Rica]

Sibon lamari, a new species of colubrid snake from northeastern Costa Rica is described on the basis of six specimens. The new form differs from the closely allied S. annulatus in color pattern, head size, subcaudal count, and number of labials bordering eye-orbit. This is the third species of Sibon, together with S. argus and S. longifrenis, possessing a green dorsal ground color in Costa Rica. Sibon lamari coexists sympatrically with S. annulatus, S. argus. S. longifrenis and S. nebulatus at the locality of Guayacán de Siquirres (Limón Province).

Public health policy paradoxes: science and politics in the Rockefeller Foundation's hookworm campaign in Mexico in the 1920s

The origins of US international health endeavors are intertwined with the Progressive Era's faith in science as arbiter of humankind's secular problems. No agency better exemplifies the period's confidence in science than the Rockefeller Foundation's International Health Board (IHB), which set out to export the new public health theory and practice around the world. An examination of the IHB's hookworm program in Mexico in the 1920s demonstrates that, notwithstanding the Rockefeller Foundation's (RF) self-conscious commitment to scientific neutrality, its programs continuously engaged political criteria, exhibiting the competition, coexistence, and inseparability of the worlds of science, politics, and international health policy. Analysis of the program's quotidian decisions and larger strategies further reveals the protean quality of RF science-politics, which enabled responses to parochial and broadly-conceived needs at multiple levels. In the focus on hookworm, the selection of campaign sites, hookworm diagnosis methods, treatment procedures, definition of cure, and the assignment of responsibility for prevention, scientific and political considerations were inextricably bound. The science-politics paradox was molded by the hookworm program's constituencies in Mexico, including political leaders, health bureaucrats, physicians, business interests, public health workers, peasants, and Rockefeller officers. The multiple, often contradictory, roles of the RF's hookworm campaign are characteristic of the policy paradoxes that emerge when science is summoned to drive policy. In Mexico the campaign served as a policy cauldron through which new knowledge could be demonstrated applicable to social and political problems on many levels. The repeated pledge of scientific neutrality belied the hookworm program's inherent aim of persuading government officials, the medical community, business interests, and the populace of the value of investing in public health as a means to improve social conditions, further a medical model of health and sickness, increase economic productivity, and promote good relations between the US and Mexico.

Yeast positive-stranded virus-like RNA replicons. 20 S and 23 S RNA terminal nucleotide sequences and 3' end secondary structures resemble those of RNA coliphages

Saccharomyces cerevisiae strains carry single-stranded RNAs called 20 S RNA and 23 S RNA. These RNAs and their double-stranded counterparts, W and T dsRNAs, have been cloned and sequenced. A few nucleotides at both ends, however, remained unknown. These RNAs do not encode coat proteins but their own RNA-dependent RNA polymerases that share a high degree of conservation to each other. The polymerases are also similar to the replicases of RNA coliphages, such as Qbeta. Here we have determined the nucleotide sequences of W and T dsRNAs at both ends using reverse transcriptase polymerase chain reaction-generated cDNA clones. We confirmed the terminal sequences by primer-extension and RNase protection experiments. Furthermore, these analyses demonstrated that W and T dsRNAs and their single-stranded RNA counterparts (i) are linear molecules, (ii) have identical nucleotide sequences at their ends, and (iii) have no poly(A) tails at their 3' ends. Both 20 S and 23 S RNAs have GGGGC at the 5' ends and the complementary 5-nucleotides sequence, GCCCC-OH, at their 3' ends. S1 and V1 secondary structure-mapping of the 3' ends of 20 S and 23 S RNAs shows the presence of a stem-loop structure that partially overlaps with the conserved 3' end sequence. Nucleotide sequences and stem-loop structures similar to those described here have been found at the 3' ends of RNA coliphages. These data, together with the similarity of the RNA-dependent RNA polymerases encoded among these RNAs and RNA coliphages, suggest that 20 S and 23 S RNAs are plus-strand single-stranded virus-like RNA replicons in yeast.

Doctors and corporatist politics: the case of the Mexican medical profession

This study advances our understanding of the relationship between the state and the medical profession in countries where health care services are used as instruments of economic and political control. As a general argument, we maintain that the corporatist nature of the Mexican state impedes the medical profession from achieving autonomy and control over its professional activities. In contraposition to medical professions in developed societies, the nature of the Mexican profession is shaped by state policies and by its reiterated efforts to act independently of the state's tutelage. We analyze this dynamic interaction through three different historical epochs that reflect the complexity and uniqueness of the Mexican medical profession. Whatever attempts the profession has made to control the medical curriculum, the licensing process, the market, or the specific laws that affect its own field, the Mexican state has responded with measures that systematically divide and antagonize the different factions of medical associations. The result is a highly fragmented and disenfranchised medical profession with dissimilar political, professional, personal, and academic aims. In the final analysis, the interests of the corporatist Mexican state prevail over the interests of the groups, including doctors. The evisceration of the medical corps by the Mexican state results in a profession with low salaries, higher rates of unemployment, atomization in terms of political representation, and heavily co-opted medical organizations that seem to neglect the overwhelming health care needs of the Mexican people.

Sowing the seeds of neo-imperialism: the Rockefeller Foundation's yellow fever campaign in Mexico

The Rockefeller Foundation's campaign against yellow fever in Mexico sought to advance the economic and political interests of U.S. capitalism. The campaign was implemented at a time of strong anti-American sentiments on the part of the Mexican people. With no diplomatic relationships between Mexico and the United States, the Rockefeller Foundation presented its campaign as an international commitment. Thus, Foundation doctors became the most salient U.S. diplomats. At the same time they made sure that the Mexican yellow fever would not spread to the United States through the southern border. The by-products of the campaign went beyond the political arena. Special techniques to combat the vectors allowed the Rockefeller Foundation's brigades to change the anti-American sentiments of the people. When the campaign ended, the Foundation had already set in place the foundation for the modern Mexican health care system. Benefits from the campaign also accrued to President Obregón, who used the campaign to strengthen his position of power. Mexican doctors adopting a pro-American attitude also allied with the Rockefeller Foundation to gain reputation and power within the emerging Mexican State.

[The serum of newborn Clelia clelia (Serpentes: Colubridae) neutralizes the hemorrhagic action of Brothrops asper venom (Serpentes: Viperidae)]

The ability of serum from nine newborn specimens of Clelia clelia (Colubridae) to neutralize hemorrhagic action of Bothrops asper venom was tested. All serum samples neutralized completely the hemorrhagic effect of the venom in mice. This finding shows that the neutralizing ability of C. clelia serum towards the hemorrhagic activity of B. asper venom is innate.

[Reproductive cycles of the coral snake Micrurus nigrocinctus (Serpentes: Elapidae) in Costa Rica]

The coral snake Micrurus nigrocinctus has two reproductive patterns in Costa Rica. Specimens of the Pacific population (M. n. nigrocinctus) mate during the early dry season (November, January). Oviposition takes place in February and March; the mean number of eggs was 7.9 (5-14) in this population. Births occur between April and June after 47-81 days of incubation. The total length of neonates is 168-212 mm, and the weight is 1.2-2.0 g. Specimens of the Atlantic population (M. n. mosquitensis) seem to have an extended breeding season. Oviposition in this subspecies was observed in March and June; the mean number of eggs was 6.7 (5-8). Births take place in May and August, after two months of incubation. Neonates have 173-189 mm in total length and 1.9-2.4 g in mass. Adult females are longer than males, especially in M. n. mosquitensis.

[Bothrops ophryomegas Bocourt (Serpentes: Viperidae) in Costa Rica: distribution, lepidosis, sexual variation and karyotype]

The distribution, karyotype and morphological characteristics of Bothrops ophryomegas from Costa Rica are described. This species presents a conspicuous sexual dimorphism and dichromatism. It is distributed in the dry forest areas of Guanacaste and Puntarenas. Its karyotype is indistinguisable from those described for other crotaline species.

[Reproductive biology of the Central American rattlesnake Crotalus durissus durissus (Serpentes: Viperidae) in Costa Rica]

In Costa Rica, rattlesnakes mate during the early dry season (December and January) and births occur in the early rainy season (May-July). Gestation is therefore about 6 months. The mean number of offspring is 22.9 and is significantly correlated with the size of the female. Newborn rattlesnakes are 27.5-43.0 cm in length and weight 11.4-46.3 g. They are relatively docile. Adult males are longer and heavier than females. Females seem to have their first litter when their size exceeds 120 cm.

[Karyotype study of 5 species of Costa Rican snakes of the colubrid family]

The karyotypes of five species of colubrid snakes from Costa Rica are as follows: Imantodes cenchoa and Drymobius margaritiferus have a diploid number of 36, with 16 macro- and 20 microchromosomes. The fourth pair is heteromorphic in females of I. cenchoa, with a metacentric Z and a submetacentric W chromosomes. Karyotypes of Erythrolampius bizonus and Leimadophis epinephalus have 28 chromosomes, without a clearcut separation between macro- and microchromosomes. In the case of E. bizomus, the fourth pair contains the sex chromosomes Z and W, both are submetacentric, but the W is smaller. Xenedon rabdocephalus has a diploid number of 34 chromosomes (22 macro- and 12 microchromosomes); pair 3 is heteromorphic in females, with a submetacentric Z and a smaller metacentric W. The karyotype of X. rabdocephalus may be derived from a primitive karyotype by means of reduction in the number of microchromosomes and centric fissions of two pairs of metacentric autosomes.