The Magnitude of Global Marine Species Diversity

Background: The question of how many marine species exist is important because it provides a metric for how much we do and do not know about life in the oceans. We have compiled the first register of the marine species of the world and used this baseline to estimate how many more species, partitioned among all major eukaryotic groups, may be discovered. Results: There are ∼226,000 eukaryotic marine species described. More species were described in the past decade (∼20,000) than in any previous one. The number of authors describing new species has been increasing at a faster rate than the number of new species described in the past six decades. We report that there are ∼170,000 synonyms, that 58,000–72,000 species are collected but not yet described, and that 482,000–741,000 more species have yet to be sampled. Molecular methods may add tens of thousands of cryptic species. Thus, there may be 0.7–1.0 million marine species. Past rates of description of new species indicate there may be 0.5 ± 0.2 million marine species. On average 37% (median 31%) of species in over 100 recent field studies around the world might be new to science. Conclusions: Currently, between one-third and two-thirds of marine species may be undescribed, and previous estimates of there being well over one million marine species appear highly unlikely. More species than ever before are being described annually by an increasing number of authors. If the current trend continues, most species will be discovered this century

The Annual Cycle of Oogenesis, Spawning, and Larval Settlement of the Echiuran Listriolobus pelodes off Southern California

Listriolobus pelodes lives in aggregated populations in fine-grained sediments along the mainland shelf from northern California to Baja California, Mexico. This echiuran forms U-shaped burrows and uses its proboscis to feed on the uppermost layer of sediment deposited around the burrow apertures. The bacterial flora of the sediment may be an important food source. Commensals in the burrow include a polychaete, a pinnixid crab, and a small bivalve. The annual reproductive cycle of a population off Palos Verdes, California, is defined in terms of coelomic oocyte dynamics, spawning, and larval settlement. Small oocytes are released from the gonad through most of the year but fully grown oocytes are present only from mid-fall through spring. It is estimated that the coelomic phase of oogenesis lasts about 5 months. Fully grown oocytes are removed from the coelomic fluid in the germinal vesicle stage and accumulate in the storage organs until spawning. Spawning takes place in winter and spring and individuals are spawned out by summer. An annual influx of small juveniles into the population occurs in late winter and spring. The newly settled juveniles reach sexual maturity when they are 6 months to 1 year old

Concentrations of urinary 8-hydroxy-2'-deoxyguanosine and 8-isoprostane in women exposed to woodsmoke in a cookstove intervention study in San Marcos, Peru

Nearly half of the world's population is exposed to household air pollution (HAP) due to long hours spent in close proximity to unvented cooking fires. The effect of woodsmoke exposure on oxidative stress was examined by investigating the association between woodsmoke exposure and biomarkers of DNA oxidation (8-hydroxy-2'-deoxyguanosine [8-OHdG]) and lipid peroxidation (8-isoprostane) among control and intervention stove users. HAP exposure assessment was conducted within the framework of a community-randomized controlled trial of 51 communities in San Marcos Province, Cajamarca Region, Peru. The first morning urine voids after 48h HAP exposure assessment from a subset of 45 control and 39 intervention stove users were analyzed for 8-OHdG and 8-isoprostane. General linear models and correlation analyses were performed. Urinary oxidative stress biomarkers ranged from 11.2 to 2270.0μg/g creatinine (median: 132.6μg/g creatinine) for 8-OHdG and from 0.1 to 4.5μg/g creatinine (median: 0.8μg/g creatinine) for 8-isoprostane among all study subjects (n=84). After controlling for the effects of traffic in the community and eating food exposed to fire among all subjects, cooking time was weakly, but positively associated with urinary 8-OHdG (r=0.29, p=0.01, n=80). Subjects' real-time personal CO exposures were negatively associated with 8-OHdG, particularly the maximum 30-second CO exposure during the sampling period (r=-0.32, p=0.001, n=73). 48h time integrated personal PM2.5 was negatively, but marginally associated with urinary 8-isoprostane (r=-0.21, p=0.09, n=69) after controlling for the effect of distance of homes to the road. Urinary 8-isoprostane levels reported in the available literature are comparable to results found in the current study. However there were relatively high levels of urinary 8-OHdG compared to data in the available literature for 8-OHdG excretion. Results suggest a sustained systemic oxidative stress among these Peruvian women chronically exposed to wood smoke

Problems of news culture and truth: the BBC's representation of the invasion of Iraq

This article considers the truth value of the BBC's reporting of the invasion of Iraq in the context of Hannah Arendt's consideration of the US invasion of Vietnam. Arendt theorized that the ‘Pentagon Papers’ exposed a new approach to truth and lies – the ‘modern political lie’ at the heart of modern politics. In this article, Arendt's concept of the modern political lie is examined and comparisons made with Iraq. A case study of the BBC's coverage of the invasion is used to argue that its reporting did not necessarily lie about Iraq, nor did it necessarily create a discursive representation separate to the physical actions of the protagonists. Rather, it appears that strategic considerations on the part of the invading powers changed the factual texture on the ground, which reporting failed to keep up with