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Sunday, February 28, 2010

Giant marsupials (animals with a pouch)

There is an interesting podcast entitled "Dr. Karl's Great Moments in Science" that I was listening to the other day.  He was talking about spotted hyena's and their character traits. One ability they have is to break bones easily with their strong jaws.

He referenced a paper written by Stephen Wroe from the University of Sydney. The paper is called Bite Club and it compared animals of all sizes to their bite force quotient.  He wanted to know which animal could bite down the hardest compared with their body size.

Wroe studied mammals and marsupials, both alive and extinct.  He found that marsupials have a greater bite force quotient, and it was also higher in those animals who consistently attacked animals bigger than themselves .

"The spotted hyena scored 117 on the bite-o-meter, only slightly ahead of the lion at 112, but behind the tiger (127), the African hunting dog (142) and well behind the Tasmanian devil at 181. The all-time winner was the now-extinct Australian marsupial lion at 196."

That made me curious about marsupials.  I had never heard of a marsupial lion.  Here are some facts I learned.

The marsupial lion lived in Australia tens of thousands of years ago.  One complete and seven nearly complete skeletons were found in limestone caves on Australia's Nullabor Plain in 2002.  The animals would have been  6 1/2 feet long and would have weighed up to 285 pounds!  Other extinct animals, including carnivorous kangaroos and a giant wallaby, were also found.  If you would like to read the story, go here.

In South America there lived a marsupial saber tooth cat. The scientific name is thylacosmilus.  Here is a picture of a skull.

The thylacine, or Tasmanian tiger or marsupial wolf, is the largest carnivorous marsupial of recent times and lived into the 20th century in Australia.  Film footage of this animal can be found here.  The last captive thylacine died in 1936.

The largest marsupial that ever lived, the diprotodon, was not carnivorous, but rather fed on trees and shrubs.  It lived in Australia also and is now extinct.  Standing on all four feet, it's shoulder height was up to 5 ft. 7 in.  That is my height, so imagining the size of one of these is easy.  They were ten feet from nose to tail. The males weighed up to 5,500 pounds, which is slightly larger than a white rhino. They looked a little like a rhino without a horn except it had hair like a horse. It is believed to have the pouch facing backwards like a wombat, instead of forward like a kangaroo.

One more interesting marsupial I found was a giant marsupial frog.  It is not a mammal, but has a pouch on its back where their eggs are stored until it is time for them to hatch.

Now you have heard something interesting.

Monday, February 22, 2010

The last of "Bury the Chains"

The island of St. Dominque, owned by the French, had the largest slave population in the Caribbean.  With half of a million slaves, they far outnumbered the forty thousand whites who lived there.  It was "the crown jewel of all European colonies anywhere."  It produced more than 30 percent of the world's sugar and more than half its coffee, as well as cotton and other crops.

In 1791 there was a revolt.  The slaves had been planning in secret to all rise up at the same time.  Drumbeats were the signal.  For miles around, everything was destroyed by fire, machetes, and pruning hooks.  The French soldiers responded quickly.  There was terrible brutality from both sides. Pleas of help were answered with arms and ammunition from Britain.

In the 1790's, France was in turmoil.  The revolution there had claimed the lives of many in the ruling classes, including King Louis XVI who lost his head by the guillotine on January 21, 1793.  The revolution spilled over the English Channel as France declared war on England on February 1.

With war on the minds of the people, the abolition movement came to an end for the time being.  The book calls it the "Bleak Decade."  During this time Clarkson and Wilberforce both married.  Slavery increased and more West India docks were built in London.

"War fever seemed to wrap slavery tightly in the British flag, as the country's most popular military hero, Lord Nelson, declared that he would battle any threat to 'our West Indian possessions ... while I have an arm to fight in their defence, or a tongue to launch my voice against the damnable doctrine of Wilberforce and his hypocritical allies.'"

When I read this quote, I was astonished that Lord Nelson had made this comment that he would "battle. . . .  while I have an arm to fight in their defence...."  My surprise came because of what happened to Lord Nelson just a few years later.  He lost his right arm in battle in 1797.  There is some kind of poetic justice or irony here.

After the war broke out between Britain and France, the British wanted St. Dominque for themselves.  It would increase, by a large margin, their numbers of sugar and coffee plantations.  The British sent ships and soldiers to fight.  But, "pomp triumphed over common sense, and successive shiploads of fresh troops disembarked in tight-fitting red uniforms of heavy wool, made for fighting on the snowy plains of northern Europe.  The army refused to abandon the famous red coat, or the regulation flannel underwear.  In the intense, humid heat, the layers of flannel and wool became drenched in sweat, creating a covering as thick and clammy as a modern surfer's wetsuit and bringing on heat stroke."

By 1798, it was clear that the British were fighting a losing battle.  In Edmund Burke's words, "it was like fighting to conquer a cemetery."  The British withdrew.  In 1802, the French sent an initial thirty-five thousand men to recapture St. Dominque.  After a twenty-two month attempt to retake the colony, France had lost more than fifty thousand men.  Napoleon suffered more casualties in St. Dominque than he would at Waterloo.  Because of this great loss of lives and money, he decided to sell a great tract of land to the United States for a much needed $15 million. Yes, that's the one.  The Louisiana Purchase.

On January 1, 1804, after the only successful slave revolt in history, St. Dominque became Haiti, the first independent black state in the new world.

Slavery, on paper, was abolished in the British Empire in 1833, but because of technicalities, the real triumph came on August 1, 1838 when nearly 800,000 men, women, and children finally became totally free.

Now you have heard something interesting.

Saturday, February 20, 2010

Happy stories from "Bury the Chains"

The Sierra Leone Company in England, known as The Company among its associates, was striving to establish a colony for freed slaves in Sierra Leone, on the continent of Africa.  One problem was that it was an active place for the capturing and selling of slaves.  The Company was undaunted, however, and a colony was begun with both whites and blacks living side by side.  There were some troubles, but here are three sweet stories from that time.

In 1792, Thomas Clarkson's younger brother, John, escorted more than 1,100 former slaves from Nova Scotia, Canada, to Sierra Leone.  These stories from the book really touched me as I imagined what it would be like for them to return to the place where their slavery began.  This is a direct quote from the book.

"The immigrants Clarkson accompanied to Sierra Leone from Canada included several who had been taken into slavery from this very river mouth.  Thirty-year-old Frank Peters, a former slave in South Carolina, found the precise spot were he had been captured  to be sold to an American slave ship, fifteen years before. Then one day, in the words of a Company official, an elderly local woman showed 'very peculiar emotions' when she saw Peters; 'she ran up to him and embraced him: she proved to be his own mother.'  He resettled for a time in his own village.

"John Gordon, a lay Methodist leader in North America, had been sold from Bance Island when he was about fifteen.  Four years after arriving back in Sierra Leone, he would meet the man who kidnapped him.  He gave his captor a present and told him, 'Your thoughts were evil, but God meant it for good -- I now know God and Christ.'

Another black settler, Martha Webb, recognized her mother in a chain of slaves being led into captivity and, with a gift of wine, persuaded a local chief to let her go."

Now you have heard something interesting.

Thursday, February 18, 2010

Tidbits from "Bury the Chains"

Here are more odds and ends from the book, "Bury the Chains" by Adam Hochschild.

As Thomas Clarkson and his committee in Great Britain worked toward freedom for slaves, they knew that turning the tide of public opinion was crucial.  It was a great day when they were able to add Josiah Wedgwood, the famous pottery designer and manufacturer, and the maternal grandfather of Charles Darwin, to the committee.  He brought with him not only money, but also a talent for publicity and marketing.  After he was made Potter to the Queen, for example, he quickly sold a line of china he called Queensware. 

Wedgwood arranged for one of his craftsmen to design a seal for stamping the wax used to close envelopes.
It shows a kneeling slave with the words: "Am I not a man and a brother" inscribed around the figure.  It was reproduced everywhere "from books and leaflets to snuffboxes and cufflinks." Several ladies wore them as bracelets and as ornaments in their hair.  It became the equivalent of the buttons we wear for political campaigns.

This certainly raised awareness on the question of the slave trade.

Wilberforce was not a big man.  Just 5' 4" tall, he was prone to bad health.  The debates in Parliament were sometimes postponed as he battled illness.  Once, when he was particularly sick, his weight plummeted to 76 pounds!

In April 1791, during a debate on the House floor, William Wilberforce emphatically insisted  that ending the trade of slaves would not hurt, but rather help, the plantation economy.  Colonel Banastre Tarleton, who was a Member of Parliament (MP), responded that "the Africans themselves had no objection to the trade."

Unbelievable.  Simply astounding.

People all over England boycotted slave-grown sugar.  In response, the pro-slavery side wrote a pamphlet saying that sugar "is a mild, nutritious, vegetable substance; possessing a power of correcting the ill effects arising from a too free use of animal food."

Wouldn't that be interesting to see what their food pyramid looked like?  I could buy into that one.

Now you have heard something interesting.

Sunday, February 14, 2010


An ant colony functions together as a group in an interesting way.  There is a queen, but her only job is to lay eggs.  That's all she does.  She does not give directions.  There is no ant that is in charge.  Yet somehow the group is efficient in functioning with all the jobs that are required to make it run well.  This is a great example of the science of emergence: the individuals of a group coming together without formal organization and creating something as a whole.

In Southeast Asia, there are areas where fireflies live in trees along river banks.  They turn their lights off and on in synchrony.  All on, then all off.  No one in charge.  No detectable reason.  It has been described as rows of Christmas trees all lit up.  Then darkness.  Then the lights.
Synchronous Display of male fireflies in a "firefly tree" in Southeast Asia
Scientific American, May 1976

John Buck, a researcher, caught many of these fireflies and took them to his hotel room.  At first, they flashed randomly.  After a little while, they started grouping in twos and threes and would synchronize their flashing in these little groups.  Then slowly all the groups merged a few at a time until the whole room was flashing together.

In 1906, Sir Francis Galton (Charles Darwin's cousin) attended a fair and stumbled upon a contest being held.  An ox was on display, and the people were supposed to guess the weight of the animal after it was slaughtered and dressed.  Nearly 800 guesses were made, but not one was the exact amount of 1,187 pounds..  Sir Galton asked the man running the contest if he could have the papers. He took them, did the math, and found that the average weight that the crowd had guessed was one pound off - 1,188 pounds!

Now there are experiments at colleges all over the United States.  A professor, usually a psychology professor, will put a bowl of jelly beans in front of the class and ask the students to guess the number of jelly beans.  Over and over again, there will not be one who guesses correctly, but often the class as a whole, when averaged out, will guess the correct number.  It would be a fun experiment to try, I think.

Google became the giant of search engines using this idea that a group of people as a whole can be more accurate than a single person.  They decided that every time someone linked to a web page, it was counted as a vote.  Now when you wonder who decided what page should come up first in a search, the answer is everybody and nobody.  It is another example of emergence.

For the full WNYC RadioLab podcast, go here.

Now you have heard something interesting.

Saturday, February 13, 2010

Amazing Grace

One of my most favorite movies is "Amazing Grace."  It is the story of the end of the slave trade in England.  I always watch it with subtitles so that I can soak up every bit.  It always amazes me how courageous some people are.  I wish I were courageous.

There is a book that tells the story of two of the men, William Wilberforce and Thomas Clarkson, in more detail than the movie does.  It is "Bury the Chains: Prophets and Rebels in the Fight to Free an Empire's Slaves" by Adam Hochschild.  I am really loving it.

Here is a story from the book.  The blog is a little long, but well worth the read.

In 1783 in England, the Quakers were the only group of people openly opposed to slavery.  But they were on the fringe of society, not the social elite. Their efforts were mostly ignored.  They were conspicuously different.  For instance, in deference to God, Quaker men would uncover their heads when preaching or praying, but would never doff their hats to a mere mortal, even to royalty.

In that year, there was an insurance fraud case that came to trial.  It was brought to court because the insurance company didn't want to pay for the 133 slaves that had been thrown overboard while they were still alive as the ship, the Zong, crossed the Atlantic Ocean.  Slaves were thought of as property, so this was not a case of murder.  The captain had reported that they were low on water and had to dispose of the sick ones so the others would survive.  His first mate testified in court that this was not true.  He was just loosing too much money because of many delays and knew he could make money with the insurance.

Granville Sharp was a prominent man who was fighting slavery, and wrote angry letters about this court case.  Most of these letters were ignored, but directly or indirectly the news reached a prominent Anglican clergyman, Dr. Peter Peckard.  The next year Dr. Peckard became vice-chancellor - the equivalent of an American university president - of Cambridge University.  In 1785 he set as the topic for Cambridge's most prestigious Latin essay contest the question "Is it lawful to make slaves of others against their will?"

One of those who entered the contest was twenty-five-year-old divinity student, Thomas Clarkson.  He was very ambitious and worked hard to win that essay.  He read all he could, managed to get access to the papers of a slave merchant who had recently died, and sought out several people who had witnessed slavery firsthand.

His essay won first prize. Afterward, he took the prize money and headed to London.  As he rode he thought on that essay and at one point, he got off his horse, and "sat down disconsolate on the turf by the roadside and held my horse. Here a thought came into my mind, that if the contents of the Essay were true, it was time some person should see these calamities to their end."

Only gradually did it dawn on him that he was that person.

After arriving in London, the Quakers sought him out.  They were aware of his essay, and were happy to have another person join in the antislavery fight. In May 1787, a dozen men started a planning committee.  Nine Quakers and three Anglicans, including Clarkson and Granville Sharp.

They decided to try and stop the slave trade first (the buying and selling of slaves) and fight for emancipation later.

Clarkson spent sixty years in the struggle for freedom.  At both his funeral procession and the overflowing church where the service was held, the mourners included many Quakers, and the men among them made an almost unprecedented departure from long-sacred custom.

They removed their hats.

Now you have heard something interesting.

Wednesday, February 10, 2010


The book "Ghost Map" by Steven Johnson is about a terrible cholera outbreak in 1854 in London. Hundreds of people died in a very short period of time in a small neighborhood.  Cholera is an intestinal disease that is spread through unsanitary waste systems. It was an interesting book describing how the problem was solved. It was traced back to one water pump in the neighborhood. 

I love indoor plumbing.

Here is an especially fascinating detail in the book that really caught my attention.

The search for unpolluted drinking water is as old as civilization itself.  As soon as there were mass human settlements, waterborne diseases like dysentery became a crucial problem.  For much of history, the solution to this chronic public-health issue was not purifying the water supply.  It was to drink alcohol. In a community lacking pure water supplies, the closest thing to "pure" fluid was alcohol.  Whatever health risks were posed by beer (and later wine) in the early days, were more than offset by alcohol's antibacterial properties.  Dying of cirrhosis of the liver in your forties was better than dying of dysentery in your twenties.

Alcohol is a deadly poison and notoriously addictive.  To digest large quantities of it, your body needs to increase the production of certain enzyme called alcohol dehydrogenases.  Many living in rural areas lacked that ability, and were genetically unable to "hold their liquor."  Many of these died childless at an early age, either from alcohol abuse or from waterborne diseases.

Over generations, the gene pool became dominated by those who could drink beer on a regular basis.  Most of the world's population today is made up of descendants of those early beer drinkers, and we have largely inherited their genetic tolerance for alcohol.

The descendants of hunter-gatherers - like many Native Americans or Australian Aborigines - were never forced through this genetic bottleneck, and today they show higher rates of alcoholism than the general population.

This same genetic tolerance story is true of lactose, which went from a rare genetic trait to the mainstream among the descendants of the herders, thanks to the domestication of livestock.

Now you have heard something interesting.

Sunday, February 7, 2010

Tarantula silk

Spiders can produce seven different types of silk.  Not every spider has every kind, but every male has at least three and every female has at least four, the extra one being for egg sacs.  Here are the types.
     *swathing silk (wrapping prey)
     *web silk (elastic and sticky for catching prey)
     *draglines (connects spider to web as a safety line - strongest silk)
     *parachuting (dispersal of young or to find a new area for food - silk is released and caught by wind)
     *shelters (burrows or nests)
     *egg sacs
     *mating (male spiders weave sperm webs on which they deposit sperm and subsequently transfer it to their front palps, ready for placing on a females genital organs.  Spiders usually have two palps. They are located on the front and look like tiny claws or thick antennae.  They are a sensory organ.)

Not every spider spins a web. Those who do spin webs know where to walk to avoid the sticky parts.  Webs are made from protein, which costs much for the body to produce.  In anticipation of spinning a new web, a spider will eat the old one and recycle that protein.  Very efficient in terms of energy.

Now there is another type of silk that has been found..  The researchers, led by Stanislav Gorb of the Max-Planck-Institute in Stuttgart, Germany, coaxed zebra tarantulas to walk up a piece of vertical glass.  When the spider began to slip, it would send out strands of silk from nozzles at the ends of all eight
legs.  These strands stopped the spider's descent, leaving visible silk that allowed it to adhere to the glass for more than twenty minutes.

The story is detailed in the Sept. 28, 2006 issue of the journal Nature.

Now scientists want to know more about this newly-found silk.  How is it related to the other known types? Did all spiders once have this ability in their feet?
Nexia Biotechnologies scientists in Canada took a spider gene that is used for silk production, injected it into a single cell of a goat egg, and produced a goat named Willow.  Then they made a whole herd of goats with this spider silk gene.  The milk that Willow and the other goats produced had the same proteins that spider silk has.  Using that protein, they produced a material they call BioSteel.  It could be used in medical and micro-electronic applications.  Bullet-proof vests are also a possibility. BioSteel has been demonstrated to be stronger and lighter than steel or Kevlar. But Nexia Biotechnologies has failed as a company.  In 2006 they were left with a herd of  40 "franken-goats", some patents, and some cash.  You can go here to read the publication.

Now you have heard something interesting.

Thursday, February 4, 2010

Broken Windows theory

The Broken Windows theory was first published in an Atlantic Monthly article in 1982 and talked about in the book The Tipping Point by Malcolm Gladwell where I read about it. It was written by James Q. Wilson, a political scientist at Harvard, and George L. Kelling, a criminologist.  This theory suggests crime is the inevitable result of disorder.  If a window is broken and left unrepaired, people will conclude that no one cares.  Soon more windows will be broken and the disorder will spread to the street.

In the mid-1980s, Kelling was hired by the NY Transit Authority as a consultant, and he urged them to put the Broken Windows theory into practice.  They agreed, and hired David Gunn to oversee a multibillion-dollar rebuilding of the subway system.  Many people thought that Gunn should not worry about the graffiti. "Worrying about graffiti at a time when the entire system was close to collapse seems as pointless as scrubbing the decks of the Titanic as it headed toward the icebergs."

But Gunn didn't listen.  The cars on the subway were reclaimed one at a time.  Graffiti was either painted over or cleaned with solvent as soon as possible.  "Dirty" cars with graffiti still on them were never to be mixed with "clean" cars.  The idea was to send a strong message to the vandals.

The cleanup took from 1984 to 1990.  At that point, the Transit Authority hired William Bratton to head the transit police, and the second part of the reclamation of the subway began.  Bratton believed in the Broken Windows theory.  His first step as police chief seemed impractical.  With felonies on the subway system at an all-time high, Bratton decided to crack down on fare-beaters.  He believed they were like the graffiti, inviting bigger crimes.  Up until this time, the transit police didn't feel that fighting over a $1.25 fare was worth it, especially when more serious crimes were happening on the platform and on the trains.

Bratton picked stations where fare-beating was the biggest problem, and put as many as ten policemen in plain clothes at the turnstiles.  The team would nab fare-beaters one-by-one, handcuff them, and leave them standing on the platform until they had a "full catch."  The idea was to signal, as publicly as possible, that the police were serious on cracking down.  Checks were run on all those arrested.  One of seven had outstanding warrants for previous crimes, and one in twenty was carrying a weapon of some sort.  Bratton writes, "For the cops it was a bonanza.  Every arrest was like opening a box of Cracker Jack. Got a gun? Got a knife? Got a warrant? Do we have a murderer here? After a while the bad guys wised up and began to leave their weapons home and pay their fares."

In 1994 Rudolph Giuliani was elected mayor and appointed Bratton to the NYC Police Department.  He applied the same strategies to the city at large.  His officers cracked down on quality-of-life crimes: on the "squeegee men" who came up to drivers at NYC intersections and demanded money for washing car windows, on public drunkenness, on public urination, and on relatively minor damage to property.  When crime began to fall in the city - as quickly and dramatically as it had in the subways - Bratton and Giuliani pointed to the same cause.  Minor, seemingly insignificant quality-of-life crimes, they said, were tipping points for violent crimes.

Now you have heard something interesting.

Wednesday, February 3, 2010

Age, brain function and focus

Many studies confirm that those who lead mentally active lives have better brain function.

"The Brain That Changes Itself" by Norman Doidge states that we are less likely to get Alzheimer's disease or dementia under these conditions:
1. the more education we have
2. the more socially and physically active we are
3. the more we participate in mentally stimulating activities.

Not all activities are equal.  Those that involve genuine concentration -- studying a musical instrument, playing board games, reading, dancing -- are those associated with a lower risk of dementia. These studies stop short of proving that we can prevent Alzheimer's disease with brain activities. The most that can be said at the moment is that it seems very promising.

Nothing speeds brain atrophy more than the lack of stimulation. It is better to continually learn new things, which plays a role in being happy and healthy in old age.  Finding something one has always wanted to do is best, because it will be highly motivational, which is crucial.  David Ben-Gurion, the first prime minister of Israel, taught himself ancient Greek in old age to master the classics in the original.  At ninety, the architect Frank Lloyd Wright designed the Guggenheim Museum in New York City.

At seventy-eight, Benjamin Franklin invented bifocals.  This last one I am especially grateful for.

When Pablo Casals, the cellist, was ninety-one years old, he was approached by a student who asked, "Master, why do you continue to practice?" Casals replied, "Because I am making progress."

Neuroplasticity is the ability for our brains to change.  They are always changing.  Michael Merzenich, a neuroplastician, has shown how these brain-processing areas transform.  He claims that plasticity exists from the cradle to the grave, and that radical improvements in how we learn, think, perceive and remember are possible even in the elderly.

These claims are from a man who has made a name for himself in this area of science.  Early in his career, he and his group developed the most commonly used design for the cochlear implant, a device to help congenitally deaf children to hear. He also developed Fast ForWord, which is disguised as a game for children, but has helped hundreds of thousands of learning-disabled students improve their ability to learn, understand, and retain that knowledge.

When we learn, we obviously increase what we know.  But Merzenich has shown that we can also change the structure of the brain itself and increase its capacity to learn.  Unlike a computer, the brain is constantly adapting itself.  It doesn't just learn, it is always learning to learn.  Our brain is not a vessel to fill, but more like a living creature with an appetite, one that can grow and change itself with proper nourishment and exercise.

In numerous experiments, Merzenich discovered that paying close attention is essential to long-term plastic change.  When we perform tasks automatically, without paying attention, we change our brain maps, but the changes do not last.  We often praise the "ability to multitask."  While we do learn when we divide our attention, this kind of attention doesn't lead to abiding change in our brain maps. It takes focused attention to make those long-term changes.

So when doing homework, the question might be, "How long do I want to retain this knowledge?" If the answer is: just long enough to pass the test, then the distractions don't really matter.

Now you have heard something interesting.