AQUACULTURE

Aquaculture. No, it’s not a typo. Instead of farming cultivated plant foods we’re farming fish. And this year, we’ve reached a tipping point of sorts. The Washington Post reports that now, over ½ the fish consumed in the world will have been raised in pens, rather than caught. The implications are enormous.

Several years ago, I began the marine biology course that I taught at TA with a graph that showed the projected decline in ocean fish. The numbers of fish had been declining for several decades, but the frightening part was the projection out to the year 2050. The endpoint for this graph suggested that the oceans would be depleted of all fish. In other words, while a few species might survive in unique niches, fish - from the sharks to the scavengers – would disappear from our oceans. The oceans in a sense would become relatively lifeless pools of flooded sand.

The predator prey relationships of the past have been permanently altered given the huge increase in human population (from 1 billion to the current 6 billion in about 150 years). That increase, coupled with a commensurate increase in the world’s taste for seafood has lead to some drastic over fishing. Cheap, smaller fish are also being caught in massive numbers to be ground up into fish meal, to be fed to poultry, pigs, and ironically – farmed fish. In other words, fish are being hunted and caught to feed people. And fish.

Another article this past week discussed the imminent demise of the large blue fin tuna, a magnificent half-ton beast that is capable of swimming 3000 miles without stopping. Tuna, it seems, is about to become a victim of the global sushi craze. Tuna can’t be farmed. They are too large, too energetic, and they require too much space.

But other species can be grown from “egg-to-plate” as they say. Salmon are probably the best known and most popular of the farm-raised fish. Once considered a delicacy, salmon has literally become the “chicken of the sea”. I remember salmon selling for about $10/pound in the 1970s – that’s probably something like $25/pound today. Now, I see it selling for as little as $3.95 locally. Salmon, and now other fish, are becoming cheap and plentiful because they are being farmed, raised in huge circular pens like the one pictured above.

The fish are born into the tanks. They are raised on a diet of unused poultry trimmings from the millions of chickens that are raised in dark boxes, corn meal, and antibiotic powders. Not being free to swim the oceans, the fish also accumulate more body fat than a free, “wild” fish. This trait is particularly noticeable in farm-raised salmon. Genetically chosen for hardiness, and the ability to live in these conditions, the fish that you are eating are different from the fish your grandparents ate.

Shellfish too, are being farmed. Scientists report that some Chinese bays are so congested with nets, traps, and pens that they have become un-navigable. Lest you think this is an “Asian problem”, let me assure you that New England is one of the fastest growing fish farm regions in the country.

This is an unsustainable practice. As we deplete the oceans of its largest fish, and its small foraging fish, we are decimating the two ends of the oceanic food chain. Krill too – the small shrimp-like plankton that lays the foundation for the oceanic food web is also being sieved out of the Antarctic waters at alarming rates. Such over-fishing can lead to an environmental chain reaction of sorts. In the 1970s and again in the 1990s Peru exploited its anchovy population. Anchovies are small foraging fish. Not only did fish stocks decline, but so did local sea bird populations that depended on the small fish for their food. It took a change in government in 2006 to place restraints on fishing. Restraints that have lead to a recovery of the ecosystem.

That was the experience of a small, regional ecosystem. What happens when we deplete an ocean? What happens if the chain reaction truly starts, and species begin to disappear at an accelerating rate? What happens if the projections are correct, and the oceans do become dead zones in the next few years? What does it mean if the earth no longer has seafood?

What will happen to our poultry industry? What will happen to us?

Maybe we're the chickens who have lost their heads.

ZOOMING IN ON A LEAF

This 3 minute video is really cool, despite the corny voice-over narration. This is one leaf - what does this suggest about the biological detail found in a complete plant? Or in a tree?

Watch the video, and provide your thoughts and comments. (Again, you may have to cut and paste the link if it does not appear live on your computer)

www.scienceblogs.com/grrlscientist/2009/09/zoom_into_a_leaf.php

WHERE HAVE ALL THE FLOWERS COME FROM?

This initial post addresses what Darwin called an abominable mystery - the origin of flowers.

We have seen how most of our modern garden flowers originated in China, and have even seen images of what could possibly have been the "First Flower". But was it actually the first? Scientists are continuing their work in this field - literally and figuratively. Scientists are fairly certain that Amborella, pictured above, is the oldest lineage of flowering plant. It appers to be an ancient species going back millions of years.

For the rest of the story, click on the link below (or cut and paste the link into your address bar if the hyperlink does not work on your computer) and read the article that appeared in the New York Times yesterday on this very topic. Type up your first response, as we discussed in class, and you're on your way!

What is it that flowers provided that their predecessors, the "naked seed" plants, did not?

www.nytimes.com/2009/09/08/science/08flower.html?8dpc

LET YOUR MIND DANCE.....

TA faculty have been spending much of our meeting time this past year writing, and reviewing standards. As I've thought about the standard on Reflection, I've found my own self reflecting on the phrase "let your mind dance", some words that came to mind while writing a Zoobot post earlier this year. This morning, as I was doing my usual Sunday morning web surfing, I came across an article in The New Republic about President Obama's Secretary Of Energy, Steven Chu that starts with a great example of this:

"In the winter of 1984, a young scientist named Steven Chu was working as the new head of the quantum electronics division at AT&T's Bell Labs in Holmdel, New Jersey. For months, he'd been struggling to find ways to trap atoms with light so that he could hold them in place and study them better. It was an idea he'd picked up from an older colleague, Arthur Ashkin, who had wrangled with the problem all through the 1970s before finally being told to shut the project down--which he did, until Chu came along. ("I was this new, young person who he could corrupt," Chu later joked.) Now Chu, too, had hit an impasse until, one night, a fierce snowstorm swirled through New Jersey. Everyone at Bell had left early except for Chu, who lived nearby and decided to stay a bit longer. As he watched the snow drift outside, he realized they'd been approaching the problem incorrectly: He first needed to cool the atoms, so that they were moving only as fast as ants, rather than fighter jets; only then could he predict their movements and trap them with lasers. It was a key insight, and Chu's subsequent work on cooling atoms eventually earned him a share of the Nobel Prize in physics. While it may sound inevitable in retrospect, big breakthroughs like that don't come along too often."

This anecdote captures perfectly the idea of letting your mind dance. Sometimes we face problems, assignments, situations, or blog responses not knowing how to start. Whether its a paper or a painting, what is the first word or brushstroke to put on the paper or canvass. This anecdote emphasizes the importance of non-active thinking. Letting the mind wander. Looking out the window. Giving yourself the opportunity to relax enough to allow your mind to forge some natural connection between what you already know and what it is you are trying to grasp - that elusive idea that lies just beyond your reach.

I emphasized the final sentence in the New Republic piece, because it too raises an important aspect of letting your mind dance. Very often the outcome - that big breakthrough - seems inevitable when it becomes explicit. I'm sure that every Chem 1 student would know that atomic motion slows down as temperature decreases. But it took a moment of wonder (yes, and a pretty smart guy) to experience the epiphany that this simple fact could be applied in an entirely new way in order to achieve an elusive research goal.

Let your mind dance on this last thought for the semester: Current studies indicate that the Silverback Gorilla will be extinct in 30-50 years. Ishmael’s epitaph includes the statement: “With the Gorilla gone, will there hope for man”? Reflect on this statement. Dance around some of the information you gleaned from reading The Sixth Extinction article several weeks ago on the library’s lawn a couple of weeks ago. Share your thoughts.

My summer wish for all of you is that you allow yourselves the opportunity, nay - that you make multiple opportunities - to relax and let your minds dance.

Peace- out.


Posted by Gary at 4:16 AM 0 comments

THE HUMAN FOOTPRINT

For students, from Katie:

Five points on photosynthesis quiz for completing this survey and recording or saving results to share...:

http://www.myfootprint.org/en/visitor_information/

ZOONOSIS

Uh-oh.

During the past few years, I have discussed avian flu (bird flu) occasionally, and somewhat cautiously, in class. I'm not a "catastrophist", someone who sees disaster lurking around every corner. I believe that climate change is real, but I also have faith in mankind's ingenuity to adapt and change. I didn't get concerned about the alleged Y2K virus that was to have shut down all personal computers, as well as global air traffic control networks, train systems, banking systems, and other computer based management systems. And as I told my wife Sue several years ago, I wasn't too concerned about avian flu, "Unless", I told her "the virus jumps into pigs - that would concern me".

Consider me concerned.

There are about 15 known strains of virus. Some effect birds/water fowl. Some effect humans. The organisms are genetically different enough in these two classes that viral strain rarely jump from one class (Aves) to another (Mammalia). There are a few viral strains however, that effect birds, swine, and humans. Swine are mammals. We are mammals. Swine there can act as a viral bridge, allowing an avian flu to "migrate" into, and infect, humans.

This transmission of disease from animals to humans is called zoonosis. (I can hear Jenny now, bristling at the notion that humans are not animals, and we consider ourselves, somehow "different". A perfect segue into our next book, Ishmael.) We may in fact be animals, but viruses seem to specialize and distinguish between different classes of animals. This distinction has shielded humans from many diseases.

The swine flu being reported in Mexico is a combination of avian and swine flu. At this time, it is being reported in Mexico, New York, California, Texas, Kansas, Israel, New Zealand, France and Hong Kong. Human immune systems are encountering this bug and saying "Huh? What's this?" Not knowing how to respond, those who are infected find themselves with immune systems going into overdrive - sometimes to their own detriment.

If I were to make a hypothesis it would be this: we are about to see a global pandemic. The first wave will be relative mild with relatively few infections. Then, Darwinian principles will kick in, the "strongest viruses will survive" and adapt to Tamiflu or whatever is being used against them, and a second, more serious wave of viral infections will occur. It's important to keep all of this in perspective. Influenza is always to be treated as a potentially serious disease. The "flu" is responsible 35,000 deaths in the US each year, mostly in our most vulnerable population groups - infants and the elderly. And there was another swine flu alert put out in 1976, but that epidemic never materialized - certainly not to anything approaching global pandemic levels.

Hopefully, I will be proved wrong (It will not be the first time!) and this whole thing will fizzle out. But this is my current thinking on the matter. Transmission is exponential; 2 pass it on to 4, and on to 8, 16, 32, 64, 128, 256, 512, 1024 etc. We should have a much clearer sense of where this thing is heading towards the end of this week.

While several people in Mexico have died, they reportedly did not seek treatment. At this point, no Americans have died from the swine flu. A primary concern is that this strain of flu seems to be targeting young, otherwise healthy teenagers and adults, rather then the typically vulnerable populations.

My advice to you all is the same advice I've given my own kids: wash your hands, follow new developments in the news, and if you begin to feel any flu-like symptoms (tiredness, joint-aches, fever, disorientation) get thee to a physician!

As disturbing as these recent developments are, I could not have planned a better illustration of what we have been studying these past few weeks. Infectious agents kick one's immune system into gear. The virus presents an antigen/epitope not previous known to one's immune system. One gets tested for swine flu with an Enzyme Linked Immuno-Sorbant Assay, and then receives treatment based on a positive or negative indicator in the test.

Sometimes the real-life connections are a little too real.

So where did this swine flu virus come from? Aren't there always viruses? How did it make the "leap" from birds to pigs to humans? How? It evolved. And that, dear students, will lead us to another relevant "real-life" connection this week as we acquaint ourselves with Darwin's elegantly simple, yet utterly profound, thoughts on the diversity of life on earth: the theory of evolution.

BIRD POPULATIONS IN DECLINE

"Evening summer breeze / sweet warblings of the meadowlark / moonlight in Vermont....."

Moonlight In Vermont. Great, great song. I was walking down the hallway past Mr. Mellinger's room last week, and heard the band practicing the tune. Stuck my head in to congratulate the musicians and singer - the song has a killer key change in the middle "bridge", and they really nailed it. Couldn't get it out of my head as I returned to the biology room....and kept thinking about that meadowlark. I couldn't recall seeing a meadowlark for a long time.

Turns out there's a probable reason for the absence. A recent study completed by the Interior Department titled "The State Of The Birds" (catchy title, eh? Just had to be a federal report...) reports that just about all non-waterfowl bird populations have dropped dramatically during the past forty years. Climate change wasn't directly implicated as the primary cuase although it most assuredly is involved. Rather, it is the spread of human populations and development of previously forested woodlands and grasslands that is to blame. As we build more houses, yards, stores, and roads we are changing, and in some cases destroying, the habitats of our bird populations. Birds that thrive in wooded areas or grasslands hesitate, or refuse, to cross over new open parcels of land, which indicate a territorial boundary to them. Invasive species move in. Disease spreads. Populations teeter on extinction.

Fortunately, bird advocates and worked with sport hunters to lobby for hundreds of millions of dollars of federal aid to protect endangered species. Yet placing birds on an endangered species list, may impact other environmentally important projects. For example, the lesser prairie chicken lives in the the southwest. Like many grassland species, its population has dropped about 40% during the last four decades. While it may deserve designation as an endangered species, doing so would place severe limitations on the entrepreneurs efforts to develop wind power turbines in that region. How does one place a value on a bird species versus the need for more, and cleaner, energy?

When I moved to the Upper Valley in the mid 1980s I was awakened each morning by a cacophony of bird song. Currently, more often than not, it is very quiet when I awaken - even on weekends. I hear the occasional song of some resident birds, but it is nothing like it was 25 years ago.

And I wonder, is this another "silent spring"? One not caused by use of pesticides, but rather, a more benign neglect in the name of progress?