We have the usual crop of articles involving DNA sequencing this issue – but I can offer you a link to Deep Sea News promising to demistify some of this – so that is where we start. DNA sequencing of a brown-tide algae helps to show how it can form these potentially harmful algal blooms. Our article on cryptic dolphins, however, uses isotope analysis to show that two sub-species are feeding on very different prey that they are finding in different locations. We pick up on isotope analysis again in pollution, where ⁷Be is used to track global pollution and rainfall – but no formal climate change section on this occasion…

Marine science

Genetics heads up: An introduction to genetics (part one) by Dr Bik in Deep Sea News (Feb 20th, 2011).

Brown tide sequenced: Aureococcus anophagefferens, which is occasionally associated with harmful algal blooms, has had its genome sequenced. The sequence shows that it is particularly well adapted to life at low light levels – with 62 genes associated with light harvesting – compared to the regular 24 or so. The ability to survive at low light levels is probably a factor enabling the formation of dense blooms. ScienceDaily (Feb. 21, 2011)

What makes you green? The chloroplast DNA from the siphonous green algae Bryopsis hypnoides has been sequenced. Chloroplasts, like many organelles in cells have their own genetic information, and in the algae (cf vascular plants) often show a degree of autonomy, as here.
Lü F, Xü W, Tian C, Wang G, Niu J, et al. (2011) The Bryopsis hypnoides Plastid Genome: Multimeric Forms and Complete Nucleotide Sequence. PLoS ONE 6(2): e14663. doi:10.1371/journal.pone.0014663

Cryptic teeth? There are a number of species that look identical, but show considerable differences at the genetic level. These are called cryptic species, and clearly it can be quite difficult to tell them apart in the wild, and so work out by observation how the different species are using their environment. Here researchers have used isotope analysis of the teeth of the Southern Australian bottlenose dolphin and the common bottlenose dolphin to show that the two species are foraging in different areas, and for different prey items.
Owen K, Charlton-Robb K, Thompson R (2011) Resolving the Trophic Relations of Cryptic Species: An Example Using Stable Isotope Analysis of Dolphin Teeth. PLoS ONE 6(2): e16457. doi:10.1371/journal.pone.0016457

Scallops fighting disease: Both molluscs and vertebrates have lectins, which are important in recognising invaders in the body. In scallops, however, the lectins may take on the role played by immunoglobin in vertebrates.
Yang J, Wang L, Zhang H, Qiu L, Wang H, et al. (2011) C-Type Lectin in Chlamys farreri (CfLec-1) Mediating Immune Recognition and Opsonization. PLoS ONE 6(2): e17089. doi:10.1371/journal.pone.0017089

Reef slows down: Reefs in the Gulf of Honduras off Belize have been sampled to monitor their average growth rates over the last 20-80 years. The study shows that the fore reef – that closest to the open ocean, has shown most slowing in growth rate over the last 20 years, whilst growth rates in the back and near-shore reef has remained essentially constant.
Castillo KD, Ries JB, Weiss JM (2011) Declining Coral Skeletal Extension for Forereef Colonies of Siderastrea siderea on the Mesoamerican Barrier Reef System, Southern Belize. PLoS ONE 6(2): e14615. doi:10.1371/journal.pone.0014615

Snakes in the sea: Marine snakes have a slightly increased volume of red blood cells in their blood stream, to help carry oxygen, permitting prolonged periods of immersion.
Brischoux F, Gartner GEA, Garland T Jr, Bonnet X (2011) Is Aquatic Life Correlated with an Increased Hematocrit in Snakes? PLoS ONE 6(2): e17077. doi:10.1371/journal.pone.0017077

Hot tubes! A synthesis of research on deep sea tube-worms in the family Siboglinidae attempts to answer when they evolved, and how they have adapted to life with their bacterial hosts. The paper suggests that they are related to the peacock worms, which have a fossil record going back to the Late Triassic, though their own fossil history is less clear. Different species have evolved close endosymbiotic relationships with a number of species of chemosynthetic bacteria, which are acquired by juvenile worms from their environment.
Hilário A, Capa M, Dahlgren TG, Halanych KM, Little CTS, et al. (2011) New Perspectives on the Ecology and Evolution of Siboglinid Tubeworms. PLoS ONE 6(2): e16309. doi:10.1371/journal.pone.0016309

Conservation

25 endangered turtles: The Wildlife Conservation Society (WCS) has issued a list of the 25 most endangered turtle species. Turtles are threatened by human activity – directly through hunting for food and the pet trade, and indirectly through habitat loss. Two of these species have fewer than five remaining individuals… ScienceDaily (Feb. 21, 2011)

Coral disease linked to human population size: The reef-building corals Acropora and Porites are both susceptible to tumour-like growth anomalies that make them sick. In this study the density of these anomalies is found to correlate strongly with human population density.
Aeby GS, Williams GJ, Franklin EC, Haapkyla J, Harvell CD, et al. (2011) Growth Anomalies on the Coral Genera Acropora and Porites Are Strongly Associated with Host Density and Human Population Size across the Indo-Pacific. PLoS ONE 6(2): e16887. doi:10.1371/journal.pone.0016887

Local extinction prediction: Algae and invertebrate invasion are two of the primary threats to reefs that have been compromised by bleaching, disease or storms. Because grazers and invertebrate predators are generally larger fish, fisheries management may promote coral recovery. ScienceDaily (Feb. 14, 2011)

Fisheries and exploitation

SOD protects sperm: Eel spermatogonia have a high resistance to oxidative stress due to their high expression of superoxide dismutatse (SOD).
Celino FT, Yamaguchi S, Miura C, Ohta T, Tozawa Y, et al. (2011) Tolerance of Spermatogonia to Oxidative Stress Is Due to High Levels of Zn and Cu/Zn Superoxide Dismutase. PLoS ONE 6(2): e16938. doi:10.1371/journal.pone.0016938

Seaweed immunity: Some of hte chemicals used by marine seaweeds to fight off fungal attacks may be a useful lead on new anti-malarial drugs. ScienceDaily (Feb. 21, 2011)

Where have all the big fish gone? As large predatory fish such as cod and tuna disappear, smaller fish such as sardine, anchovy and capellin have increased in numbers. ScienceDaily (Feb. 19, 2011)

Pollution

Spot the alien: A microfluidic test chip for identifying alien species in ballast water.
Mahon AR, Barnes MA, Senapati S, Feder JL, Darling JA, et al. (2011) Molecular Detection of Invasive Species in Heterogeneous Mixtures Using a Microfluidic Carbon Nanotube Platform. PLoS ONE 6(2): e17280. doi:10.1371/journal.pone.0017280

Fish adapts to PCB’s: Polychlorinated biphenyls were released into the river Hudson by General Electric for 30 years up until the 1990’s. Studies have now shown that the local tomcod population has undergone genetic changes that reduce its susceptibility to this pollutant. ScienceDaily (Feb. 18, 2011)

Into each life: Using Beryllium-7 isotope measurements to estimate global rainfall and track ocean pollution. ScienceDaily (Feb. 15, 2011)

Natural eutrophication: The Baltic had lower oxygen levels a millenium ago than it does now, at a time before human activity had had much impact. ScienceDaily (Feb. 15, 2011)

Pill not at fault: Only 1% of estrogens in drinking supplies are from the birth control pill. Apparently most estrogens enter watercourses from animal husbandry. ScienceDaily (Feb. 15, 2011)