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Climate variation affects surface ocean processes and the production of organic carbon, which ultimately comprises the primary food supply to the deep-sea ecosystems that occupy [approximately equal to]60% of the Earth's surface. Warming trends in atmospheric and upper ocean temperatures, attributed to anthropogenic influence, have occurred over the past four decades. Changes in upper ocean temperature influence stratification and can affect the availability of nutrients for phytoplankton production. Global warming has been predicted to intensify stratification and reduce vertical mixing. Research also suggests that such reduced mixing will enhance variability in primary production and carbon export flux to the deep sea. The dependence of deep-sea communities on surface water production has raised important questions about how climate change will affect carbon cycling and deep-ocean ecosystem function. Recently, unprecedented time-series studies conducted over the past two decades in the North Pacific and the North Atlantic at >4,000-m depth have revealed unexpectedly large changes in deep-ocean ecosystems significantly correlated to climate-driven changes in the surface ocean that can impact the global carbon cycle. Climate-driven variation affects oceanic communities from surface waters to the much-overlooked deep sea and will have impacts on the global carbon cycle. Data from these two widely separated areas of the deep ocean provide compelling evidence that changes in climate can readily influence deep-sea processes. However, the limited geographic coverage of these existing time-series studies stresses the importance of developing a more global effort to monitor deep-sea ecosystems under modern conditions of rapidly changing climate. www.pnas.org/cgi/doi/10.1073/pnas.0908322106

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.dsr.2007.05.004 Byline: M.F. Vardaro (a)(c), D. Parmley (b), K.L. Smith (c) Keywords: Underwater photography; Ocean floor; Long-term time-lapse; Aggregation; Grenadier fish; Megafauna; USA; California; NE Pacific Abstract: The aggregation response of fish populations following the addition of artificial structures to seafloor habitats has been well documented in shallow-water reefs and at deeper structures such as oil extraction platforms. A long-term time-lapse camera was deployed for 27 four-month deployment periods at 4100m in the eastern North Pacific to study abyssal megafauna activity and surface-benthos connections. The unique time-series data set provided by this research presented an opportunity to examine how deep-sea benthopelagic fish and epibenthic megafauna populations were affected by an isolated artificial structure and whether animal surveys at this site were biased by aggregation behavior. Counts were taken of benthopelagic grenadiers, Coryphaenoides spp., observed per week as well as numbers of the epibenthic echinoid Echinocrepis rostrata. No significant correlation (r.sub.s=-0.39; p=0.11) was found between the duration of deployment (in weeks) and the average number of Coryphaenoides observed at the site. There was also no evidence of associative behavior around the time-lapse camera by E. rostrata (r.sub.s=-0.32; p=0.19). The results of our study suggest that abyssal fish and epibenthic megafauna do not aggregate around artificial structures and that long-term time-lapse camera studies should not be impacted by aggregation response behaviors. Author Affiliation: (a) Scripps Institution of Oceanography, University of California at San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0208, USA (b) Torrey Pines Institute for Molecular Studies, 3550 General Atomics Court 2-129, San Diego, CA 92121-1122, USA (c) Monterey Bay Aquarium Research Institute, 7700 Sandholdt Road, Moss Landing, CA 95039-9644, USA Article History: Received 6 January 2007; Revised 11 April 2007; Accepted 12 May 2007

The insulin superfamily, characterized by common disulphide bonds, includes not only insulin but also insulin-like peptides such as relaxin-1 and relaxin-3. The actions of relaxin-3 are largely unknown, but recent work suggests a role in regulation of food intake. Relaxin-3 mRNA is highly expressed in the nucleus incertus, which has extensive projections to the hypothalamus, and relaxin immunoreactivity is present in several hypothalamic nuclei. In the rat, relaxin-3 binds and activates both relaxin family peptide receptor 1, which also binds relaxin-1, and a previously orphaned G protein-coupled receptor, RXFP3. These receptors are extensively expressed in the hypothalamus. The aims of these studies were twofold: 1) map the hypothalamic site(s) of the orexigenic action of relaxin-3 and 2) examine the site(s) of neuronal activation following central relaxin-3 administration. After microinjection into hypothalamic sites, human relaxin-3 (H3; 180 pmol) significantly stimulated 0- to 1-h food intake in the supraoptic nucleus (SON), arcuate nucleus (ARC), and the anterior preoptic area (APOA) [SON 0.4 [+ or -] 0.2 (vehicle) vs. 2.9 [+ or -] 0.5 g (H3), P < 0.00l; ARC 0.7 [+ or -] 0.3 (vehicle) vs. 2.7 [+ or -] 0.2 g (H3), P < 0.05; and APOA 0.8 [+ or -] 0.1 (vehicle) vs. 2.2 [+ or -] 0.2 g (H3), P < 0.05]. Cumulative food intake was significantly increased [less than or equal to] 8 h following administration into the SON and 4 h into the APOA. A significant increase in Fos-like immunoreactivity was seen in the SON following central relaxin-3 administration. Relaxin-3 stimulates feeding in several hypothalamic nuclei, and these studies provide additional support for relaxin-3 as an important peptide in appetite regulation. relaxin family peptide receptor 3; appetite; supraoptic nucleus; arcuate nucleus

Food web structure, particularly the relative importance of bottom-up and top-down control of animal abundances, is poorly known for the Earth's largest habitats: the abyssal plains. A unique 15-yr time series of climate, productivity, particulate flux, and abundance of primary consumers (primarily echinoderms) and secondary consumers (fish) was examined to elucidate the response of trophic levels to temporal variation in one another. Towed camera sled deployments in the abyssal northeast Pacific (4100 m water depth) showed that annual mean numbers of the dominant fish genus (Coryphaenoides spp.) more than doubled over the period 1989-2004. Corphaenoides spp. abundance was significantly correlated with total abundance of mobile epibenthic megafauna (echinoderms), with changes in fish abundance lagging behind changes in the echinoderms. Direct correlations between surface climate and fish abundances, and particulate organic carbon (POC) flux and fish abundances, were insignificant, which may be related to the varied response of the potential prey taxa to climate and POC flux. This study provides a rare opportunity to study the long-term dynamics of an unexploited marine fish population and suggests a dominant role for bottom-up control in this system. Key words: benthic megafauna; Coryphaenoides spp.; deep water; marine fish; Pacific Ocean; population dynamics.

A long time-series study was conducted over 15 yr (1989-2004) to measure particulate organic carbon (POC) flux as an estimate of food supply reaching >4,000-m depth in the northeast Pacific. Sequencing sediment traps were moored at 3,500-and 4,050-m depth, 600 and 50 m above the seafloor, respectively, to collect sinking particulate matter with 10-d resolution. POC fluxes were compared with three climate indices in the Pacific: the basinscale multivariate El Nino Southern Oscillation index (MEI) and northern oscillation index (NOI) and the regionalscale Bakun upwelling index (BUI). The NOI and MEI correlated significantly with POC flux, lagged earlier by 6-10 months, respectively. The BUI also correlated with POC flux, lagged by 2-3 months, suggesting a direct relationship between upwelling intensity and rates of POC supply to abyssal depths. Satellite ocean color data for the surface above the study site were used to estimate chlorophyll a concentrations and, combined with sea surface temperature and photosynthetically available radiation, to estimate net primary production and export flux (EF) from the euphotic zone. EF was significantly correlated with POC flux, lagged earlier by 0-3 months. An empirical model to estimate POC flux, with the use of NOI, BUI, and EE yielded significant agreement with measured fluxes. Modeling of deep-sea processes on broad spatial and temporal scales with climate indices and satellite sensing now appears feasible.

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.dsr.2005.02.004 Byline: K.L. Smith, Nicholas D. Holland, Henry A. Ruhl Abstract: Photographs of the deep-sea floor not infrequently show conspicuous spiral fecal trails, sometimes with an enteropneust hemichordate at the leading end. Here, we report on the dynamics of enteropneust trail production and disappearance at an abyssal station. A time-lapse camera deployed in the abyssal NE Pacific (Station M, 4100m depth) photographed the same field of view at hourly intervals for 4 months in 2001-2002. Fortuitously, the final 10 days of the time-lapse sequence showed an enteropneust (of an undescribed species) abruptly appear in the field of view and spend 39h foraging and producing a clockwise, four-whorl spiral fecal trail before ascending off the sea floor. The selection of the foraging site was not obviously influenced by previous biological or sedimentation processes observed in the time-lapse photographs over the 3-month period prior to the enteropneust arrival. After departure of the enteropneust, the fecal trail degraded rapidly over the remaining 8.5 days of the deployment. In an ancillary analysis of 52 camera sled transects over a 15-year period (1989-2004) at Station M, the photographs revealed that the same enteropneust species was present in small numbers through the 1990s but increased four-fold in abundance between 2002 and 2004. Similarly, the number and length of fecal trials increased over the same period. We were unsuccessful in collecting any of these enteropneusts in a semi-balloon trawl routinely towed behind the camera sled, presumably because of their fragility. Author Affiliation: Marine Biology Research Division, Scripps Institution of Oceanography, University of California, San Diego, UCSD, La Jolla, CA 92093-0202, USA

Macrozooplankton/micronekton in the epipelagic zone (0-100 m) of the NW Weddell Sea were sampled with a 10 [m.sup.2] multiple opening-closing net environmental sampling system (MOCNESS) trawl during three cruises in 1995 and 1996. A total of 40 species were collected during all cruises. Community composition, as measured using Bray-Curtis analysis and multi-dimensional scaling, permitted separation into two groups: group 1 included samples collected during September-October 1995 and group 2 contained samples collected during April-May 1996 and November-December 1996. Zooplankton collections were dominated by Thysanoessa macrura in September-October 1995 (high pack-ice cover) and by both Euphausia superba and Salpa thompsoni in April-May 1996 (intermediate pack-ice cover) and November-December 1996 (open water). Copepods were not sampled quantitatively by the MOCNESS trawl and were not included in this analysis. Trends in measured parameters of community structure are discussed with respect to environmental characteristics during each sampling period.

Particulate nitrogen, particulate organic carbon, sediment community composition and oxygen consumption were measured for the North Pacific Subtropical Gyre. Findings showed that measurements peaked during September, and that the region's organic carbon supply meets 65% of the food demand.

Research has been conducted on Bacillus anthracis. Molecular typing system that is based on the rapidly evolving variable-number tandem repeat is described.

The movements of epibenthic megafauna at an abyssal location in the eastern North Pacific were observed through a time-lapse camera system from Feb 1990 to July 1991. Spatial patterns and temporal variation of the seven numerically dominant species of mobile epibenthic megafauna were monitored. Findings revealed the potentially huge impact that mobile epibenthic megafauna can have on benthic processes at Station M, especially those related to the utilization, processing and redistribution of particular organic material at the seabed.

Distribution and abundance of epibenthic megafauna at a long time-series station, Sta. M., in the abyssal northeast Pacific show spatial heterogeneity. The total densities among different transects are highly similar, but the distribution and density of each megafauna species varies remarkably between synoptic transects. The overall dispersion of different species is either random or aggregate. However, individual taxa show high spatial variability, both within and among transects. The spatial heterogeneity overshadows any temporal variation that might exist.

The effects of seasonal pack ice on the distribution of zooplanktons and other mesopelagic organisms were studied by examining the uppermost 100 m. of water in the northwestern Weddell Sea during the austral spring of 1992. Findings indicated that mesopelagic organisms are distributed nearer to the surface under pack ice than in open water. This makes them more vulnerable to predators such as surface-foraging seabirds.

Mobile megafaunal activity, either through mixing or repackaging of materials, contribute to the modification of the surface sediment in the deep North Pacific. Increased fluxes of particulate organic carbon and chlorophyll are due to the increase in megafaunal density in April and the area traversed by the megafaunal in May. Total area traversed by the megafaunal was measured using a time lapse camera off the central California Coast at a depth of 4100 meter from Mar to Jun 1991.

New measurements of particulate organic carbon (POC) and the mineralization of this carbon into CO2 in the North Pacific have brought these two previously conflicting processes to within 15% of agreement. This is a vast improvement over previous estimates which had found the POC rate to be as much as 97% short of what is needed to account for the observed levels of CO2 in the benthic community. The new, reconciled figures were obtained by including newly discovered episodic inputs of POC when making the calculations.

A study to characterize the near-bottom fauna in the central North Pacific Ocean was done using acoustic array, opening-closing trawl and baited traps. The acoustic array gave a low count of 0 to 1.6 animals per 100,000 cubic meters of water compared to 1.4 to 11.9 from trawl sampling. A total of 31 species were identified from trap and trawl samples. The eel Monognathus rosenblatti and four Hymenodora species showed up often in trawl samples, while the crustaceans Acanthephyra quadrispinosa and Eurythenes gryllus and the fish Coryphaenoides yaquinae showed up often in baited traps.

Electrospray data collected demonstrates the detailed dependence of volumetric flow rate through an electrospray system upon the applied voltage. Analysis is presented in order to show that the change in flow rate due to change in voltage cannot be ascribed to evaporation from the meniscus as suggested by others.

The first step of any molecular study should be to confirm the species of interest, ruling out contamination and/or DNA collection or extraction error. Despite a recent wealth of genetic and sequence data on humans and great apes, few molecular techniques are available for easily and efficiently distinguishing between hominoid species. We have developed a single-PCR assay for identifying hominoid species using lineage-specific LINE-1 (Long Interspersed Element) insertions. LINE-1 (L1) elements belong to a family of retrotransposons that have influenced the evolution of eukaryotic species for over 600 million years. L1s that inserted into the genome of a species after its divergence from its Last Common Ancestor ate unique to that species. Thus, the presence of a species-specific L1 insertion in a DNA sample positively identifies the species origin of the sample. There are 500,000 L1s in the human genome but virtually nothing is known about the L1s in other primates. We developed a technique to construct 'LOAF' libraries that contain recent L1 insertions from primate genomes. From LOAF libraries, we identified insertions that are unique to each of the great ape species. For each species-specific insertion, we developed a PCR assay capable of detecting both the presence ('occupied allele') and the absence ('empty allele') of the L1 insertion. These assays are capable of rapidly and unambiguously identifying the species of origin of a DNA sample. We are currently extending this approach to develop assays for distinguishing between Old and New World monkeys, and prosimians.