Saturday, November 24, 2007

Newfound Sea Anemones Really Get Around

Ker Than, LiveScience Yahoo News 23 Nov 07

Sea anemones normally anchor themselves to the seafloor. But new species found lurking in the waters surrounding the windswept Aleutian Islands near Alaska swim and walk across the sea floor.

Scientists discovered the anemones, which could represent two species, as well as a new species of kelp as part of a two-year scientific survey of the waters around the Aleutians.

"Since the underwater world of the Aleutian Islands has been studied so little, new species are being discovered, even today," said Stephen Jewett, a marine biologist at the University of Alaska, Fairbanks, and the dive expedition leader.

Overall, scientists say only about 10 percent of the species of life on this planet have been seen or catalogued.

The researchers are consulting experts to verify that the Aleutian anemones are in fact new species, but the consensus so far is that they are. Sea anemones are animals that typically use a foot to anchor to rocks. Some are known to detach when attacked or if their environment changes and food becomes scarce. The new species likely belong to a class of anemones that can detach and drift with ocean currents.

The kelp, dubbed Aureophycus aleuticus, is a type of brown algae that might represent a new genus, or even family (a larger biological classification that can include more than one genus), of the seaweed. Up to 10 feet long, the kelp was discovered near thermal vents in the region of the Islands of the Four Mountains.

Jewett and his team are studying the Aleutian waters to gauge the overall health of the islands and life there. Already, the team found evidence that the rugged and remote islands are not immune to human activity.

"Pollutants traveling through air and water pathways from temperate latitudes have been showing up in the area," Jewett said. "Debris and oil spills from World War II in the Aleutians have left their mark behind in unexploded ordinance and local sources of pollutants."

The team is analyzing water samples collected during dives for nutrient and oxygen levels, acidity, temperature and radioactive chemicals left over from underwater nuclear tests conducted at Amchitka Island between 1965 and 1971.

"Climate change, with changes in water temperature, wind patterns and currents, may impact the region's biological life," Jewett said. "It is important that we collect this information before any major changes occur."

Thursday, November 15, 2007

The march of the ants holds clues for humans - International Herald Tribune --- If you have ever observed ants marching in and out of a nest, you might have been reminded of a highway buzzing with traffic. To Iain Couzin, such a comparison is a cruel insult - to the ants.  Americans spend a total of 3.7 billion hours a year in congested traffic. But you will never see ants stuck in gridlock.

New freshwater stingray described from Myanmar | Practical Fishkeeping magazine --- A new genus and species of freshwater stingray has been described from Myanmar.  The new stingray, named Makararaja chindwinensis, is described from the Chindwin River (a tributary of the Irrawaddy River in northern Myanmar) in a paper by Tyson Roberts published in a recent issue of the Natural History Bulletin of the Siam Society.  Makararaja chindwinensis is closely related to the flagtailed stingray genus Pastinachus, but differs from it and other stingray genera in the family Dasyatidae in having a nearly round disc, with the dorsal surface having pearl organs and denticles so small as to appear almost lacking, 105–107 pectoral-fin pterygiophores, and tail with a long, low-lying fin fold.  Together with Pastinachus, Makararaja is considered to form a new subfamily Pastinachinae.

Wednesday, November 07, 2007

Patent round-up: Sea cucumber corneas - tech - 05 November 2007 - New Scientist Tech --- The team's artificial cornea is made from tiny collagen fibres extracted from these sea cucumbers. When placed in a centrifuge, the fibres self assemble into layers in which the fibres are aligned vertically, a structure that is very similar to the tissue in mammalian corneas. The result is a thin layer of material that is transparent and biocompatible, as well as cheap and easy to make, says the team.

Parrotfishes a key to reef stability | Practical Fishkeeping magazine --- New research has revealed that parrotfish may be the key to maintaining the stability of coral reef habitats and preventing them from transforming into a stable macroalgal-dominated condition following disturbance.  The results are published in the most recent issue of the journal Nature by Peter Mumby, Alan Hastings and Helen Edwards.  The authors used a simulation model to predict the effects of various perturbations to the system, including the effects of hurricanes, as well as the removal of herbivorous sea urchin on coral cover and macroalgal abundance on the complex forereef habitats of the Caribbean.  Macroalgae (seaweed) proliferate if dead coral is not sufficiently grazed and are capable of either arresting coral growth or overgrowing living coral.  The authors found that the macroalgae-dominated community is an alternative stable state of the ecosystem and one that is not readily reversible.

Thursday, November 01, 2007

Scientists Find Oldest Living Animal, Then Kill It - Evolution | Human | Theory | Man | Paleontology,2933,306076,00.html?=rss --- British marine biologists have found what may be the oldest living animal — that is, until they killed it. The team from Bangor University in Wales was dredging the waters north of Iceland as part of routine research when the unfortunate specimen, belonging to the clam species Arctica islandica, commonly known as the ocean quahog, was hauled up from waters 250 feet deep.