Thursday, March 26, 2009

Shy flowers on a cold spring morning in the Sierra foothills (Friday Photo)

Even as California continues to experience a drought, and the region is facing water shortages, this winter-spring has brought just enough precipitation to allow the wildflowers to blanket the Sierra Nevada foothills in a riot of colors the like of which I haven't seen in the five years I've lived in this area. My colleagues and students have noticed an increasing grumpiness in me these past couple of weeks, and part of the reason is that I really want to be out there in them thar hills traipsing through the wildflowers, not cooped up in the concrete of the Science building (where, to be fair, I have had quite a few glimpses of snowclad hills this spring - but that only makes being in the office worse!)! Why do we have spring break in April in this goshdarned valley, when actual spring has long since passed us by? I know, I know, it probably has to do with a certain religious holiday in early April - but that's a subject of a rant I'll save for another day. For now, this Friday, let me share some of my attempts to capture the fleeting beauty of spring in the Sierra foothills onto a few digital images. I've managed finally to create a Flickr album to collect these images, including this one of a dewy Baby Blue Eyes and some Goldfields (I think) apparently feeling too shy and/or sleepy to face the morning sun (last tuesday) after the equinox weekend's cold snap:

blue and yellow, turning away

Click on the picture to access the entire gallery, which I hope will provide you some relief even at your computer desk. Especially if you've been following the circus of the Texas State Board of Education this week as they've been watering down (to put it mildly) their standards on how science is to be taught in that state. (And please do let me know if I've made any errors of identification - floral taxonomy is not my forte!).

Happy Spring, wherever you are! And I also wish you total blissful darkness - or romantic candlelight - this saturday when we celebrate Earth Hour!

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Monday, March 16, 2009

Why are all earthly lifeforms lefties?

ResearchBlogging.orgWhat, you think you are not left-handed? Just because you favor your right hand to write/eat/pitch that baseball, etc.? Actually, in case you didn't already know this: deep down, at the amino acid level, we are all lefties! Southpaws, each and every one of us! That's just another one of those wonderfully weird arbitrary fact about life on earth! Amino acids, the building blocks of proteins, are fundamental to the structure and function of life as we know it on our planet (which is pretty much how we know life at all, because we haven't found any other kind - yet!) - and the atoms making up each molecule can be put together in different ways to produce configurations which are mirror-images of each other (chirality, as the chemists call it); we know this because we can make amino acids in the lab. Yet, all life-forms we know of only contain one version of the amino acids - the left-handed one from the mirror-image pair! So this is another deep molecular homology involving amino acids (like the language of the genetic code we discuss in Evolution class), which unites all life-forms on this planet with a shared common ancestor. But there is no inherent reason why that ancestor had to be a southpaw in its use of amino acids. Was it just a random accident that that is how we turned out? A new study of the famous Murchison meteorite takes on the question...



Did lefty molecules seed life? (as reported in The Scientist today): "Amino acids come in left-handed and right-handed forms, which, like a pair of human hands, are mirror images that cannot be superimposed onto each other. Yet living organisms use only the left-handed version, which presents a conundrum: There's no biochemical reason why one mirror image should be better than the other, so scientists have long debated whether life's left-handed leaning arose because of random processes or whether rocks from outer space seeded a southpaw solar system."


...and suggests an explanation: that there was a left-bias in the amino acids that rained onto early earth from our solar system!


The current study argues for the latter possibility by showing that some extraterrestrial meteorites contain an abundance of left-handed molecules. "The implications are that all life in our solar system could be the same handedness as life on Earth," Jeffrey Bada, a geochemist at the Scripps Institution of Oceanography in La Jolla, Calif., who was not involved in the research, told The Scientist.


Daniel Glavin and Jason Dworkin, astrobiologists at NASA's Goddard Space Flight Center in Greenbelt, MD, compared the ratio of left- and right-handed 5-carbon amino acids found in six primitive, carbon-rich meteorites that have an elemental composition similar to that presumably found in the early solar system. Three of these rocks were heavily left-skewed, while the remaining three showed equal handedness, or chirality, the researchers found. Of the lefty rocks, the meteorite that fell on Murchison, Australia, in 1969 -- arguably the most widely studied carbonaceous meteorite in the world -- contained the largest imbalance ever observed: a 18.5% excess of the left-handed form of the amino acid isovaline.



Or, in their own words from the abstract of the PNAS paper:


The large asymmetry in isovaline and other α-dialkyl amino acids found in altered CI and CM meteorites suggests that amino acids delivered by asteroids, comets, and their fragments would have biased the Earth's prebiotic organic inventory with left-handed molecules before the origin of life.


Amino acids found in these and other meteorites landing on earth tend to exhibit a bias favoring left chirality, suggesting our entire solar system has the same left-bias, setting life as we know it on its lefty path. And Glavin & Dworkin think they know what favored left chirality in the meteorites:


The mechanism that Glavin and Dworkin propose to explain the observed left-handed excess is that polarized light -- which is twisted and can rotate molecules -- probably set the imbalance in motion. Then, once the balance was slightly askew, water within the meteorites further drove an enrichment of left-handed amino acids in the liquid phase and relegated right-handed molecules to the solid phase. "The whole amplification is due to this process of aqueous alteration," said Dworkin.


Not everyone is convinced, yet, but the search for answers to these puzzles about life's origin continues. (Or we could simply say goddidit, and stop asking any further questions, couldn't we? but where's the fun in that?)


Reference:


Glavin, D. P., & Dworkin, J. P. (2009). Enrichment of the amino acid l-isovaline by aqueous alteration on CI and CM meteorite parent bodies Proceedings of the National Academy of Sciences DOI: 10.1073/pnas.0811618106

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Thursday, March 12, 2009

Restoring the San Joaquin Delta shouldn't be Fish V. People

via Fresno Audubon comes notice of this lecture at the Fresno downtown library next month, about the crisis in the San Joaquin Delta, which (like so many other environmental dilemmas) is falsely perceived as being about Fish vs. People:


Fish V. People: The False Dichotomy-Free EventThe False Dichotomy-Free Event:


"Thursday, April 23 - 7 p.m.

Fresno Downtown Library - 2420 Mariposa St

Sarah McCardle Room


A talk about the collapse of the Sacramento/San Joaquin Delta. Barbara Barrigan-Parrilla, the Campaign Director for Restore the Delta will discuss the consequences, causes, and proposed solutions of Delta collapse. Barbara is one of the leading advocates for a fishable, farmable, swimmable, and drinkable Delta.


About Restore the Delta: Based in Stockton, California, Restore the Delta works in the areas of public education and outreach so that all Californians recognize this region as part of California’s natural heritage, deserving of restoration. Restore the Delta advocates on behalf of local Delta stakeholders with government water agencies to ensure that water management decisions will protect and benefit local Delta communities. We encourage local Delta residents to undertake actions to ensure the Sacramento-San Joaquin Delta’s sustainability.


For more information contact Brandon Hill at 559.978.2369/ bhill968@gmail.com


Hope to see you there!"


I may miss it because I have to give a talk in UC Riverside that day - but you should go, especially if you live anywhere in the Delta catchment!

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A song for Mr Darwin, Mr. Wallace, and Mr. Matthew

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Wednesday, March 11, 2009

Regulatin' Genes is where its all at! Evo-Devo!!


Go Evo-Devo!! I guess I can skip the evo-devo lecture in the evolution class now, eh?


[Hat-tip: Pharyngula]

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Monday, March 9, 2009

Dawkins on those who would expel him from Oklahoma

In these hard and worsening economic times, one would think that politicians and state legislatures have their hands full with a huge number of serious issues to deal with. Instead, one congressman in Oklahoma is upset about a mild-mannered English (as in from England, not of) professor visiting a state campus to deliver a lecture! Who might that professor be? Why Richard Dawkins, of course, who got State Representative Thomsen upset enough to propose a formal resolution to condemn Dawkins' visit to University of Oklahoma last friday! Really?! So what did the good professor have to say when he did arrive in the good state? Watch:










Meanwhile, as Dawkins' US tour continues, even into the heart of the bible belt as in this case - we here at Fresno State have something else to look forward (backward?) to: Ben Stein is coming to campus next week! Yes!! That's who is the featured guest this month in the University Lecture Series! Weep, my fellow Darwin's Bulldogs... and if you do go to his talk, please ask him who is being "Expelled" from academia, exactly?


Hat-tip: OneGoodMove

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Sunday, March 8, 2009

Mysteries in the Kingdom of the Blue Whale

KingdomOfTheBlueWhale.jpgMy daughter and I just previewed (as did Kevin Zelnio of Deep Sea News) National Geographic's new documentary "Kingdom of the Blue Whale" premiering tonight at 8:00 PM on the NatGeo channel here in the US. The girls (3 and almost 9) were skeptical at first, especially because it had interrupted something else they were watching while waiting for brunch, but really got into it as the story unfolded. The younger one - no surprise - loved it whenever they actually showed the creatures underwater, culminating, of course, in the amazing first-time-ever footage of an infant Blue Whale. That comes at the end, of course, but the story leading up to it is quite fascinating too, told as it is in two intertwining threads which gradually pulled in 9-year old Sanzari:


One strand follows biologists tagging and tracking the whales from the California coast all the way into the warm tropical "nursery" of the Costa Rica dome (watch the show to find out what a "dome" might mean in the ocean), trying to solve the puzzles of their life-cycle, which is surprisingly poorly understood for the largest creatures on the planet! Sanzari, who spent a year in the field with her mom studying another charismatic yet elusive (and much smaller!) mammal, the Slender Loris, in the forests of southern India, could relate to the challenges of tagging the whales, but couldn't quite imagine tracking them across half an ocean! Tough to scale up from tracking the tiny lorises, hard enough to track in their several hectare sized home-ranges, to creatures occupying half of the world's biggest ocean!! She therefore enjoyed it when the biologists got their payoff after months on the ocean, including sad episodes when they found whales dead from being hit by ships!


Intertwined with this is a second thread which follows researchers investigating the whale meat market in Japan, using undercover operatives and portable genetics labs set up in hotel rooms! Exciting stuff, especially when they teamed up with a local female biologist who posed as a regular shopper to obtain samples from the whale meat market; and when they hung up the "do not disturb" sign on their hotel door to set up the portable genetics lab to extract DNA from the samples. What Nancy Drew fan wouldn't want to do such investigative work? Although we did wonder why the biologists weren't simply collaborating with Japanese scientists to analyze the samples in a proper lab?! What's the story there?


The whale-meat trade itself provoked some anger in the girls (carnivorous though they both are), with the sushi-loving Sanzari fuming all the way through about the Japanese and the Icelanders who wouldn't stop hunting whales! The genetic findings from one sample were even more intriguing to me... but I better not give that away before the show airs, eh? If you can't wait, or don't get the channel, check out this clip on the show's website.


What I can't resist giving away, however, is this money-shot at the end, when the first team finally caught up with a mother and infant:




I am simply amazed that we share our planet with such magnificent creatures - and also that we know so little about even some of the largest living animals! And I hope we can find ways to ensure that my girls' generation, and future ones too, get the opportunity to see the Blue Whales thrive once again.

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Wednesday, March 4, 2009

God, Darwin, and the Culture Wars - Ethics Center Lecture

Today, at noon, the Ethics Center Lecture series @ CSU-Fresno will plunge into the culture wars with the following lecture:


March 4: Leonard Olson, God, Darwin, and the Culture Wars


12-12:50 PM in the Alice Peters Auditorium (in the University Business Center)


Most observers would agree that there is something like a cultural war taking place in America today, especially over the question of the origins of life on Earth. Is the choice as simple as one between evolution or creation? Extremists on both sides frame the issue poorly. As a result, a reasonable middle position is ignored. This talk will examine the middle and criticize the extremes.


Leonard Olson is a Lecturer in the Department of Philosophy at CSU-Fresno, where he has been teaching ethics courses since 1986. A native of the Central Valley, he was educated at San Francisco State and U. C. Davis.

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Tuesday, March 3, 2009

Is teleological thinking hardwired into our brains?

ResearchBlogging.org

And is that the basis of the popularity of creationism? Perhaps, says a new study on human susceptibility to unwarranted teleological explanations of natural phenomena, including that ultimate in teleology - creationism! Dr. Fred Schreiber shares a report from New Scientist on the paper by Kelemen & Rosset, with the following comment:


A similar problem to the one below has been shown in physics students. Quiz them outside of the physics class, they forget Newton and revert to Aristotelian physics. There seem to be intuitive ways of thinking that have evolved to be "good enough" for survival purposes but as scientific explanations are completely wrong. The classic demonstration of this is a set of video interviews at a Harvard graduation. Students and faculty members were asked why do we have seasons and everybody got it wrong. They reverted to intuitive, personal experience physics. - Fred

We are all apparently born with a broad bias for accepting or inventing teleological (purpose-based) explanations for natural phenomena. The perhaps surprising finding of this study is that college education may do little to undo this intuitive inclination for "promiscuous teleology" which remains prevalent even among well-schooled adults! Interestingly, our teleological bias appears to take over most often when we are pressed for time, so that our knowledge of actual causality (established through science and learnt, hopefully, in school) is inhibited under time-pressures! So our first leap towards an explanation may often be a teleological one - and I can see some potential survival benefit of that: fine distinctions between "that leopard is leaping towards me because it wants to eat me" (warranted) and "that rock is tumbling towards me because it wants to crush me" (unwarranted) matter little when the response in either case is to "RUN"!! If we sit down to think about the scenarios (as opposed to experiencing them in real time), and have some knowledge of leopard behavior and gravity, we are perfectly capable of making the distinction between the two, and deducing that the leopard's purpose may indeed be to eat me, while the rock is simply falling with no such purpose. So the trouble (or philosophical muddle) may begin when we blur the distinction and extend the unwarranted teleological explanation into an ultimate one: "someone designed that rock (leopard) to fall (leap) on me in order to kill me" - and place ourselves at the center of all "purpose" in the universe. At what point, and how, do we develop the knowledge-based "inhibitory control" mechanisms to suppress the initial teleological urge and accept a more evidence based rational explanation for phenomena? What strategies might we use to strengthen these inhibitory controls if we are to build a more science-based culture? Something to ponder for us all, esp. those engaged in education...


Reference:


Deborah Kelemen, Evelyn Rosset (2009). The Human Function Compunction: Teleological explanation in adults Cognition, 111 (1), 138-143 DOI: 10.1016/j.cognition.2009.01.001

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