Simple Eyes of Only Two Cells Guide Marine Zooplankton to the Light

piggy submitted, created time 1 month 2 weeks (www.sciencedaily.com)

Researchers unravel how the very first eyes in evolution might have worked and how they guide the swimming of marine plankton towards light.

Larvae of marine invertebrates – worms, sponges, jellyfish - have the simplest eyes that exist. They consist of no more than two cells: a photoreceptor cell and a pigment cell. These minimal eyes, called eyespots, resemble the "proto-eyes" suggested by Charles Darwin as the first eyes to appear in animal evolution. They cannot form images but allow the animal to sense the direction of light

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Plankton diversity gradient

sea-maid submitted, created time 7 months 2 days (www.pnas.org)

From this result of this study, we know that the latitudinal gradient in marine bacteria supports the hypothesis that the kinetics of metabolism, setting the pace for life, has strong influence on diversity.

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Planktos sea cooling project goes belly-up. A blessing (poorly) disguised?

Darkfrog submitted, created time 10 months 3 weeks (www.nytimes.com)

A company called Planktos had planned to reverse global warming. Their method: chuck a lot of iron in the ocean so that plankton blooms absorb CO2. They've run out of funding. Planktos blames a "disinformation campaign."

Frankly, I think the iron oxide was a dumb idea anyway. Just because we have natural plankton blooms occasionally doesn't mean that a huge artificial one wouldn't do more harm than good. Besides, the plankton would just release the carbon again once they died.

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Convention discourages ocean fertilization

Low genomic diversity in tropical oceanic N2-fixing cyanobacteria

kitty submitted, created time 1 year 2 months (www.pnas.org)

High levels of genomic and allelic microvariation have been found in major marine planktonic microbial species, including the ubiquitous open ocean cyanobacterium,Prochlorococcus marinus. Crocosphaera watsonii is a unicellular cyanobacterium that has recently been shown to be important in oceanic N2 fixation and has been reported from the Atlantic and Pacific oceans in both hemispheres, and the Arabian Sea.

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Weird jellyfish from over 7000m below the surface

deepsea submitted, created time 1 year 4 months (www.jamstec.go.jp)

The Agency for Marine-Earth Science and Technology (JAMSTEC: Mr. Yasuhiro Kato, President) have observed a comb jelly (Ctenophore*1) of unique morphology. Analysis of images obtained in Ryukyu Trench, which is approximately 200km south off of Okinawa main island, showed it is highly possible to be a newly-discovered species and different from any currently known ctenophore.

The images were captured during the training dive of the ROV KAIKO on the sea floor at a depth of 7,217m in the Ryukyu Trench (2425N, 12775E : Appendix) on April 5, 2002

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Tiny organisms remember the way to food

athena submitted, created time 1 year 9 months (www.newscientist.com)

SOME of the most basic organisms are smarter than we thought. Rather than moving about randomly, amoebas and plankton employ sophisticated strategies to look for food and might travel in a way that optimises their foraging.

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