Monday, April 1, 2013

How to tell a woodpecker from a monkey

The 1700-1800's were great times for intrepid naturalists and collectors of insect and plant specimens who traveled the world in search of exotica.  Alexander von Humboldt was one.  From 1799-1804 he traveled throughout the Amazon region of South America, collecting specimens and taking notes for his extensive 21 volume description of his travels. Humboldt brought scientific instruments and a belief that much could be understood through systematic observation to his travels.

Darwin's 5 year voyage
Charles Darwin and Alfred Russel Wallace were both inspired by Humboldt's work as they set off on their own travels.  Darwin, of course, spent 5 years as naturalist on The Beagle, traveling around South America, Africa, Australia and back again to England.  He collected thousands of specimens himself, sending them back to various contacts and museums throughout his journey.  (His handwriting on the labels he attached was so bad that curators curse him for it to this day.)

Wallace first went to Brazil, but, not being of the upper class as Darwin was, his purpose was as much to make his living by selling specimens to interested collectors back in England as it was to document the flora and fauna he found there.  He spent 4 years in Brazil.  When, in 1852 he finally set sail to return to England with most of his collection, 26 days into the voyage the ship caught fire and all were forced to abandon ship.  His entire collection and most of his notes were lost.  Then, from 1854-1862 he traveled the Malay Archepelago, collecting specimens and making notes.  It was there that, in a malaria-induced fever, he first intuited his theory of evolution by natural selection, which motivated him to write to Charles Darwin suggesting his theory.  This in turn, as is well known, motivated Darwin to finally write the book he'd long been contemplating, his Origin of Species, describing the same theory.    

And these are only three of the best known explorers, people who set out for foreign shores knowing little to nothing of what they would find there.  We had occasion to think about this yesterday, as we were out walking in the woods on the first real spring day of the year.  Ahead of us by about 50 yards was a young couple.  He was American, she Chinese.

A pileated woodpecker called its eerie warlockian call in the distance.  If you don't know the sound, here it is.

We had caught up to the couple by then, and as we passed we heard him say, "No, it wasn't a monkey!  It was a bird!"  And they were laughing.

We laughed, too.  But not derisively.  It was lovely to imagine thinking we might be surrounded by monkeys in our local woods!  And indeed, how would she know?  Perhaps she came from a part of China where it was common to see monkeys, though whether they sound like pileated woodpeckers is a question we can't answer.

This incident of gentle innocence is in itself harmless of course, and even humorous.  But it shows how very easy it is for people from different, far-flung places, even intelligent educated people, to have deep misunderstandings of each other's world.  How might we do were we to take a walk in a wood somewhere in China?  And think about how much moreso this kind of naive misperception or expectations can be for each other's worldview. 

Were Humboldt, Darwin and Wallace better informed about the flora and fauna of the regions they explored when they first arrived than this woman about central PA?  In fact we don't know, but how could they have been?  They did work with various guides, ranging from European settlers or missionaries, or natives who were bilingual, and so on, so they were surely quickly disabused of any such innocent mistakes.  Until Europeans had explored these areas and settled more systematically, there were no guides to birds or insects or lizards -- or rocks, or trees, or flowers.  In a sense that was what they were trying to do, in good Enlightenment tradition, systematically observing and cataloguing what they saw. But they must have made a great many mistakes, until someone who lived there and knew better set them straight.

Where does ambiguity end and knowledge begin?
Indeed, in science we believe that we try to bridge understanding-gaps by being precise in our terminology, and stating our hypotheses and designs in unambiguous, logical, and specific terms. And, scientists at least tend to believe that we try to collect data objectively and without preconceived notions as to what we'll find.  After all, objectivity is our purported aim, is it not?  Or is it?

The extent and intricacies of science within areas like genetics or evolution are such that they can be most fully within the reach of only narrow specialists.  The rest of us have to assume we know what 'gene' or 'adapted' or 'function', or even 'next-generation sequencing'  actually mean.  And these are relatively simple compared to other issues that we face (like multiple-test correction, various other statistical niceties, and so on).  So someone coming in from another field could easily make the 'monkey' mistake, and be viewed as incredibly naive.

But there's more.  We are often, or even typically, clearly not trying to be 'objective' except in some rather technical senses of accurately describing our methods (e.g., the pH of our PCR reactions, our significance testing p-values, and so on).  When it comes to what 'hypothesis' we've chosen to 'test', what aspect of something we've chosen to study, our interpretations, or the issues we've stated (or not), what is clear is something rather different:  to a great extent all of us, even in science, have our preferences, assumptions, and predispositions to believe and hence prove (but not really test).

So one can wonder, when we as scientists are presenting their work, whether what's being heard is a monkey.....or just a bird.

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