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?

The Panther

Katie's lecture on our Fast Plants' anthers got me thinking about TA panthers. One thing lead to another, and before I knew it, a famous little poem by Ogden Nash came to mind:

The Panther

The panther is like a leopard,
Except it hasn't been peppered.
Should you behold a panther crouch,
Prepare to say Ouch.
Better yet, if called by a panther,
Don't anther.

A little poem that should be in everyone's memory bank I think. Connections. Even if they appear a little random at times. Let your mind dance.

OK - please proceed to this week's actual post below!

MEET THE BEETLE!

Wow.
Yes, it's real, but the question of course is: Why? If evolution is driven by natural selection for best fit within an organism's environment, what possible advantage could such armor provide? Why on earth would a beetle develop such horns? Why for that matter would an Irish elk (now extinct) carry around a rack with a width of 10-12 feet and a weight of 70-90 pounds? And why on earth would a peacock develop those beautiful, yet extraordinarily cumbersome feathers? When in flight, peacocks make turkeys look as graceful as geese.

Darwin theorized that another evolutionary process was at work in cases such as these. He called it sexual selection. Basically, Darwin theorized that females would choose mates who would offer the most protection, or the most successful hunter, or highest quality genetic material. Recent studies seem to bolster this idea.

Researchers tried shortening some of the plumage on male peacocks. Not dramatically - just a few inches. Yet the outcome was indeed dramatic in terms of preferences expressed by the peahens. Males with cut feathers were passed by in the mating process. Regardless if they were known or unknown to the females. Peahens seemed to make a conscious choice to select the males with the more extravagant plumage to father their brood.

Other organisms develop weapons to fight for the attention of the female. The Irish Elk is one of many animals that carried it's weapons around with it. Males actively fight for the females' attention. The greatest warrior won. Many examples of this remain today.

In the case of the rhinosaurus beetle pictured, an evolutionary arms race began millions of years ago that lead to the pronounced claws on the beast. This dung beetle doesn't merely push its ball of dung along a path for furtive consumption. It burrows under the dung, and drags the dung into its own tunnel network for storage and consumption. These tunneling beetles have developed their armor and huge claws not for defense, but rather as a warning. Two males may approach, they wave their claws, they perceive the threat to each other, and one will aver and back away. Claws may interlock, and the combatants may assess their relative strength, rather than inflict actual damage. Males can signal the intent, as well as their relative strength. And once again, females notice this, and it plays a role in sexual selection.

What about humans? As noted in the NY Times article which discussed this, our teeth are puny. We don't have claws. We don't look terribly menacing. (Well, most of us) But we DO manufacture our weapons. We do signal our intent. Think of the samaurai's sword. Or the military parades of tanks and gun carrying soldiers. Or the opening of the movie Iron Man.

But I gotta tell you - if I can find a helmet on eBay that looks like this rhinosaurus beetle....it's mine.

(the article on which this post is based can be found at http://www.nytimes.com/2009/03/24/science/24armo.html?pagewanted=1&ref=science)

The Right Whale (early post for Anya!)

As you know, this past Friday I attended a workshop. The keynote speaker, and workshop presenter, was Tom Wessels, author of Reading The Forested Landscape, and a professor of biology and environmental science at Antioch College. (btw Katie, he says "hello"). Tom's presentation was wonderful, but his talk was full of the caveats that biologists seem so focused on at this point in time; ie, climate change, loss of habitat, species extinction etc. At the end of the workshop, we talked, and I asked him how he responds to his students when they ask the same question I here from many of my students: Is there any good biology news? It all seems so bleak - what can we do? What can we hopeful about?

Tom told me that he responds by telling his students that we are, indeed, on the verge of a sixth "great extinction", but not to despair - human life as we know it will disappear but life, and the earth, will go on to renew itself and prosper.

Oh. Somehow I was hoping for more.

Fortunately, I read an article in the New York Times which offered me more hope. A lot more hope.

As some of you know, I'm very interested in the history of whaling in the United States. Whaling was a brutally hazardous way of making a living, but a necessary one. Whaling providing the world with a much needed commodity: whale oil. Whale oil lit the world prior to the invention of the light bulb. And whale oil was an important energy source prior to the discovery of the oil fields in the Middle East, and the creation of the refineries that created gasoline.

Whalers lead dangerous lives. The hunters' prey were the objects of callous and brutal hunting practices. In one famous historical incident, the Whaleship Essex was repeatedly rammed by a ferocious bull Sperm Whale who decided that he had taken enough. This incident probably served as the model for Herman Melville's creation, Moby Dick.

The Right Whale is a calm, slow, curious behemoth of the North Atlantic. It has lots of oil and baleen, (used by the mammal to filter food out of its waters, and used by humans for corsets), it swims close to the shoreline, and when killed, it floats on the water's surface. Curious, slow, docile, full of oil and easy to retrieve. Whalers of the 19th century named it for what it was: the right whale to kill.

By 1900, Right Whales were hunted to the brink of extinction. Their worldwide population had dwindled down to 100. Scientists were certain that the large mammal, that typically gives birth to a single calf, would not reproduce at a rate needed to sustain the population. In other words, the Right Whale appeared to be heading to certain extinction.

But a funny thing happened. People began to care about whales. Their value as an eco-tourist entity (ie,whale watching trips) began to out value their market value as a resource. As a result, many countries, including the United States, began to put legislation in place to protect the Right Whale, and other marine mammals.

During the past couple of decades the Right Whale, and several other species, have given scientists cause for hope. In 2001, a record number of Right Whale calves were born - 31. This past year, the record was broken with the birth of 39. These numbers have little to do with ocean habitat change, or food availability, or changes in acid precipitation. Rather, they're a reflection of people caring, and working to change human behaviors and their impacts on other creatures.

This article really gave me cause for hope. If we can bring the Right Whale back from the verge of extinction, there's hope for many of the other creatures currently at risk throughout the world.

Even ourselves.

I encourage you to take a look at the complete article, and its embedded slide show at
www.nytimes.com/2009/03/17/science/17whal.html?pagewanted=2&_r=1&ref=science

Oh yeah...AND THE WINNER IS.....

"Yeah, my water left me for a potato with a higher salinity concentration......"
Congratulations to Dan G.!

Please keep reading for your response to the next post...