Wednesday, January 29, 2014

David Suzuki's 59th Minute

“David Suzuki, Co-Founder of the David Suzuki Foundation, is an award-winning scientist, environmentalist, and broadcaster.  He is renowned for his radio and television programs that explain the complexities of the natural sciences in a compelling, easily understood way.”  Here’s Suzuki in an interview with Steve Curwood on 12-17-2010 on Living on Earth, an independent media program:
SUZUKI:"I give you a test tube full of food for bacteria – that’s an analogy with the planet – and I put one bacterial cell in and it is us. It’s going to go into exponential growth and divide every minute. So, at time zero, at the beginning, there is one bacterium. One minute, there are two. Two minutes, four. Three minutes, eight. Four minutes, 16. That’s exponential growth.  And at 60 minutes, the test tube is completely packed with bacteria, and there’s no food left. When is the test tube only half full? And the answer of course, is at 59 minutes. So, at 58 minutes it’s 25 percent full, 57 minutes, 12 and a half percent full. At 55 minutes of the 60-minute cycle, it’s three percent full. So, if at 55 minutes, one of the bacteria looks around and says, ‘Hey guys, I’ve been thinking, we’ve got a population problem.’ The other bacteria would say, ‘Jack, what the hell have you been drinking, man? 97 percent of the test tube is empty, and we’ve been around for 55 minutes!’ And, they’d be five minutes away from filling it. So, the bacteria are no smarter than humans. At 59 minutes they go, ‘Oh my god! Jack was right! What the hell are we going to do, we’ve got one minute left! Well, don’t give any money to those economists, but why don’t you give it to those scientists?’ And, by God, somehow those bacterial scientists in less than a minute, they invent three tests tubes full of food for bacteria. Now, that would be like us discovering three more planet Earths that we could start using immediately. So, they’re saved, right, they’ve quadrupled the amount of food in space. So what happens? Well, at 60 minutes, the first test tube is full. At 61 minutes, the second is full, and at 62 minutes, all four are full. By quadrupling the amount of food in space, you buy two extra minutes. And, how do you add any more air, water, soil or biodiversity to the biosphere. You can’t, it’s fixed! And, every scientist I’ve talked to agrees with me. We’re already past the 59th minute."

How do we know that we’ve arrived at the 59th minute when we don’t know when the 60th minute will arrive?   Although that 59th minute is a powerful analogy, it’s only an analogy –  a visual image of the exponential growth of humans on a finite planet.
Suzuki implies humans are no smarter than his mindlessly multiplying bacteria.  Thomas Malthus all over again;  Paul Ehrlich deja vu.  Suzuki rehashes Malthus who stated in 1800 that human populations multiply exponentially while resources can only grow arithmetically; therefore the humans soon run out of resources.  This idea is certainly plausible and some accept it without question.  Not only that, it has the veneer of math and science, and therefore certainty.  But is it true?  Do humans multiply endlessly like bacteria?  Are they mindless and helpless like bacteria in a culture?  What do the data show us?  What have we seen in history in the two hundred years since Malthus?
  Two hundred years after Malthus, world population has grown to seven billion.  Paul Ehrlich said forty years ago we’d run out of food in the eighties. Didn’t happen although the population has doubled since he wrote.
Why haven’t the grim predictions come true?   Possibly because machines can do a lot more work than slaves or draft animals and because of world trade in goods and ideas, people all over the world have become more prosperous since Malthus. The world’s wealth never was fixed.
Malthus left human ingenuity out of his grim calculations.  Ingenuity in communications, transportation, and especially in agriculture.  The scientific improvements in agriculture, plant breeding, irrigation, fertilizer, and pesticides, which saved a billion human beings from starvation, are called the Green Revolution. Some people oppose the Green Revolution on the grounds that it’s not sustainable.  They say increased food production has led to overpopulation, without taking the Demographic Transition, the change from high birth and death rates to low birth and death rates, into account.
As people become prosperous, death rates fall, but they continue to have many children.  The population grows exponentially for a while, but then birth rates fall as well.  In a prosperous society, people don’t need as many children to be farm hands or to take care of them in old age.  Educated women fulfill themselves with careers instead of many children.  Rather than continue to grow exponentially, the UN expects the world population to level off at about ten billion around 2050, then remain steady or decline.
Opponents of the Green Revolution claim there may have been improvements in yields, but there is still hunger because of poor infrastructure and governmental corruption.  However, these are political, not technological problems.  The Green Revolution did not claim to address the problem of food distribution.  
Another reason the Green Revolution is said to be unsustainable is because modern fertilizers and pesticides are made from fossil fuels and maybe we’ve reached peak oil.  However, methane clathrates are nearly inexhaustible. Methane plus nitrogen from the air (80% of the atmosphere) makes fertilizer, the Haber-Bosch process discovered early in the 20th century.
  Are the opponents of the Green Revolution saying the Green Revolution is unsustainable in order to get rid of those pesky carbon-spewing humans using up resources for their  grandchildren?
Not only bacteria but ideas multiply exponentially. As Matt Ridley, author of The Rational Optimist, says, “ideas have sex.”   The more people, the more communication between them, the faster new ideas are generated.  Ideas grow faster than people.  The volume of scientific papers has been doubling every fifteen years.  
There needs to be a minimum of prosperity beyond an uphill struggle for existence for ideas to flourish.  When people are educated, they can be the helpers, not the eaters.   Poverty-stricken people are just mouths to feed, but prosperous people can use their minds to invent.  
Too few people can be a bad thing.  The Tasmanian aboriginal people lacked the ability to make fire, bone tools, or to catch fish, although the Australian aborigine groups from whence they emigrated had these skills.  Jared Diamond says, “All other things being equal, the rate of human invention is faster, and the rate of cultural loss is slower, in areas occupied by many competing societies with many individuals and in contact with societies elsewhere.”
  “Every scientist I’ve talked to agrees with me,”  Suzuki claims.  Maybe he doesn’t get out much.

 FOOTNOTE:  Let’s unpack the literal image presented.  To see if it makes sense, we need to attach quantities. Starting with that one bacterial cell with an approximate volume of one microliter  [1 µl ], according to Suzuki’s thought experiment, this cell will double every minute (about ten times faster than real life bacteria) for a total of sixty doublings, which means the final volume will be two raised to the sixtieth power [2E+60] µl, a very large quantity.  Since our number system is based on ten, 20E+60 converted to powers of ten is 10E+18.
If 2E+60 = 10E+18,  the volume of the culture after sixty doublings is 10E+18 microliters in volume, equivalent to one cubic meter.  A cubic meter of water weighs a metric ton; hence the spent culture would weigh about a ton.  Mighty big test tube!
From It would take 2639 minutes or ~44 hours for an E coli bacterium doubling every 20 minutes to reach the mass of the earth!  In real life, exponential growth doesn’t continue as it does in a thought experiment. Suzuki’s 59th minute analogy is a ton (literally) of specious reasoning!

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