Necrophiliac Lesbian Worms, Viruses Eating Viruses, and Deep Sea Pollution

Been reading Discover Magazine’s Top 100 science stories of 2008, and some other assorted articles on the world that may naturally be ignored in the larger scheme of things.  A sample:

“The microscopic aquatic creatures known as bdelloid rotifers are used to enduring dry spells—in more senses than one. In their common habitats of moss, soil, and seasonal pools, these minuscule, transparent animals routinely survive periods of complete dessication that can last from days to years. They also hold the record for celibacy among animals: All 460 known species of bdelloids consist exclusively of egg-laying females that have essentially been cloning themselves for 100 million years. Their endurance has long posed a kind of scientific mystery, as the majority of asexually reproducing species tend to fade away over time. But a genetic study published in May in Science [subscription required] hints that bdelloids emerging from a drought might have a kind of bizarre sex after all.

For most life-forms, going for long periods without water spells certain doom. But dehydrated bdelloids somehow reconstitute themselves when moisture returns, even though their metabolic activity stops, their cell membranes rupture, and their DNA probably gets fragmented too. “You add water, they fix themselves up, and they swim away,” says lead investigator Matthew Meselson of Harvard University.”

And the first known case of virus preying on virus:

“Viruses, generally the most minuscule of parasites, apparently have to contend with vermin of their own. In August, infectious diseases physician Didier Raoult of the Université de la Méditerranée in Marseille, France, reported [subscription required] that he had discovered a tiny virus infecting another, a giant virus called Mamavirus. This unexpected type of attack suggests for the first time that one virus may influence the evolution of other viruses.

Raoult and his colleagues found Mamavirus in water taken from a cooling tower in Paris. The giant virus, a strain of the previously identified and slightly smaller Mimivirus, was found through microscopy to be infected by a 50-nanometer-wide virus. They named it Sputnik, after the first satellite to orbit Earth.

When the scientists cultured Mamavirus and Sputnik with an amoeba, they found that Sputnik forces Mamavirus to produce not just copies of Sputnik but fewer, and deformed, versions of itself. And when they sequenced Sputnik’s genome, they found its small ring of DNA contained genes from three different viral families, including Mamavirus.”

And best of all, persistent man-made chemical pollutants have been found in deep-sea octopods and squids:

“It was surprising to find measurable and sometimes high amounts of toxic pollutants in such a deep and remote environment,” Vecchione said. Among the chemicals detected were tributyltin (TBT), polychlorinated biphenyls (PCBs), brominated diphenyl ethers (BDEs), and dichlorodiphenyl-trichloroethane (DDT).  They are known as persistent organic pollutants (POPs) because they don’t degrade and persist in the environment for a very long time.

Cephalopods are important to the diet of cetaceans, a class of marine mammals which includes whales, dolphins and porpoises. Cephalopods are the primary food for 28 species of odontocetes, the sub-order of cetaceans that have teeth and include beaked, sperm, killer and beluga whales and narwhals as well as dolphins and porpoises.

Recent studies have reported the accumulation of POPs in the blubber and tissues of whales and other predatory marine mammals as well as in some deep-sea fish. Other investigators had speculated that the pollutants in marine mammals had resulted from feeding on contaminated squids. However, almost no information existed prior to this study about POPs in deep-sea cephalopods. Vecchione and colleagues wanted to see if whales had a unique capacity to accumulate pollutants or if they were simply one of the top predators in a contaminated deep-sea food web.

The researchers collected nine species of cephalopods from depths between 1,000 and 2,000 meters (about 3,300 to 6,600 feet) in 2003 in the western North Atlantic Ocean using a large mid-water trawl.  Species were selected for chemical analysis based on their importance as prey and included the commercially important short-finned squid Illex illecebrosus, as well as cockatoo squid, “vampire squid”, and the large jelly-like octopus Haliphron atlanticus.”