Friday, February 10, 2012

Blog Crawl Gems

Recent Treasures:  academic publishing and power to the people; personal privacy -- do we really want it?; chloroplast slurpies; the Great Unconformity; beyond plate tectonics.

The Economist took a look at the financial success of the academic publishing industry, where authors pay large sums to publish, and readers do the same to read.  Some publishers employ rather devious strategies, for example requiring libraries to subscribe to bundles of journals not just the ones they want.  No wonder a boycott of Elsevier has taken off.  Are the giants about to lose their grip, especially now that the internet makes communication so much easier and cheaper?  For additional discussion and links, see this recent post at Nature/news.

Google’s new privacy policy is looming on the horizon, to go into effect March 1, and CHIMERAS provides an interesting discussion on the topic.  So the struggle continues -- between our fear of someone knowing too much about us, and our irrepressible social nature.

The January plant blog-carnival, Berry Go Round #48, links to many great posts, including one on sea slugs that suck chloroplasts out of algae and then use them for ... photosynthesis!  Yes, solar-powered sea slugs.

Elysia chlorotica, a
"lurid green sea slug"
according to New Scientist.

There is an entire site devoted to these guys; here you can see for yourself sea slugs slurping chloroplasts.  In an earlier BCG, I mentioned that microbes are known to steal chloroplasts, but a slug? wow.  There now is a name for these stolen plastids -- kleptoplasts :)  An important question is how the plastids are stabilized in the slug.  In their normal environment, plastids are maintained in part by nuclear genes, but surely these are left behind when the chloroplasts are stolen ... or not?  There is a bit of evidence that the new host, the sea slug, may have the necessary nuclear genes ... maybe stolen from the alga ... maybe.

Next is a slightly older post, perhaps you’ve read it already.  If not, I highly recommend The Great Unconformity of the Grand Canyon by Written in Stone.  This is a lengthy post with lots of photos, about the fascinating Great Unconformity between the lower Cambrian, ca 500 million years bp, and the Paleoproterozoic, ca 1700 million years bp -- a gap of more than a billion years.  In the Grand Canyon, the gap is represented by early Cambrian Tapeats sandstone resting on early Proterozoic Vishnu schist (photo below). This is only part I, “Defining It”.  I look forward to the next installments.
Vishnu contemplates the Great Unconformity in the Grand Canyon.

Finally, Metageologist posted an introduction to continental tectonics and why plate tectonics is not enough.  The assumption that continental plates are coherent rigid structures does not work in explaining the very broad zones of deformation seen.  I should know ... the current Wyoming landscape was shaped mainly by the Laramide Orogeny, when plate collision and other plate motion along the west coast of North America resulted in as much as 40,000 feet of structural relief here a thousand miles to the east.
Why the Himalayas are not important -- they are only the front edge of the
Tibetan Plateau (see Metageologist's post for further explanation).
Metageologist includes a link to Peter Molnar’s 1988 Nature paper, Continental tectonics in the aftermath of plate tectonics, not freely available of course.  You can access From Plate Tectonics to Continental Tectonics  -- part review, part memoir -- via Molnar’s website.

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