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Posts Tagged ‘science’

Sometimes it feels good to know that you were wrong, and that you were corrected before you passed on misinformation to folks around you, and to sons and daughters. It feels even better to understand why you were wrong all along.

Growing up, I remember shelves full of atlases and dictionaries, some belonging to my grandparents, with outdated versions of the world and words, multiple sets belonging to my parents as they were growing up, and some belonging to me. My last physical dictionary upgrade was when I was in the fourth standard (fourth grade), and was presented a small Oxford Dictionary at school for I don’t remember what. By the time my younger sister arrived, we decided that physical upgrades were too expensive and occupied too much space, and we couldn’t really keep up with the rate at which the world was changing. Fast forward to now, and my prized dictionary is in tatters and I exclusively refer to online dictionaries. One such web-dictionary I have bookmarked is TheFreeDictionary (but of course) which defines ‘evolution’ in this manner:

A gradual process in which something changes into a different and usually more complex or better form. See Synonyms at development [emphasis mine].

If you have the time to read further, you will note that there is also a biological definition…

Change in the genetic composition of a population during successive generations, as a result of natural selection acting on the genetic variation among individuals, and resulting in the development of new species.

…which, you may have noted, does not make any references to increasing complexity, development, or superiority. Why does evolution, in general, connote a process that results in better forms, while evolution, in the context of biology, refer to a process that results in changes or variety? Are people aware of these differences in usage? I was not.

Images are beautiful things – they often stay in our heads more than words do, and can take the place of a lot of them. But what happens when you choose the wrong images to do your work? I don’t remember exactly what was taught in school, but I do remember hearing the phrases ‘evolutionary ladder’ and ‘evolutionary pyramid’ often. The imagery stuck, and with it the notion that the process of evolution generally leads to something ‘better’, however you define better, often culminating in man, who is somehow understood to be the most superior of earthlings. The pyramid has also been used to represent other concepts, most notably that of the Healthy Diet. In their book Switch, authors Chip and Dan Heath write:

A pyramid signifies hierarchy, yet no hierarchy is evident in the Food Pyramid. The first version of it displayed rows of food, one row on top of the next, with grains at the bottom and oils at the top. Some people interpreted this arrangement to mean that oils were the most important food group. (Whoops.)

In his relatively slim book, Full House: The Spread of Excellence from Plato to Darwin, Stephen Jay Gould attempts to correct the persistent, albeit erroneous, conventional wisdom which insists that progress or complexity is the defining thrust of the entire evolutionary process. Jay Gould, who was a paleontologist, uses examples from his own personal life, a lengthy case study of Baseball data, and an eye-opening lesson in statistics that talks in layman language about the meaningful differences between mean, median and mode and the confusion that results (sometimes intentionally) when they are used inappropriately. Jay Gould explains that life on earth did indeed start with less complex forms – bacteria and the like, and that a few creatures have indeed evolved into greater complexity in the only direction open to variation, but we have been guilty of two errors:

  • seeing trends where there are only random sequences
  • equating correlation with causality
and assuming that human beings, and other complex forms, are unique results of a directed process. We are in fact, the results of…
random evolution away from small size, not directed evolution towards large size…We are glorious accidents of an unpredicatable process with no drive to complexity, not the expected results of evolutionary principles that yearn to produce a creature capable of understanding the mode of its own necessary construction.
And we are by no means a ‘success’. The real evolutionary successes, are the bacteria.

Not only does the earth contain more bacterial organisms than all others combined; not only do bacteria live in more places and work in a greater variety of metabolic ways, not only did bacteria alone constitute the first half of life’s history, with no slackening in diversity thereafter, but also, and most surprisingly total bacterial biomass may exceed all the rest of life combined, even forest trees, once we include the subterranean populations as well.

What then did Darwin mean by ‘natural selection’ and ‘survival of the fittest’? Surely, nature selected the fitter (and better) forms to survive. Doesn’t this imply a prejudice towards ‘better’ forms?
Nope. Natural selection produces local adaptation, not general progress.The adaptation could lead as well to simplification as to complexity, and is purely in response to changing local environments. Jay Gould gives the example of the now extinct Woolly Mammoth which was better suited for colder climates, but in no way ‘superior’ to less hairy elephants, that survive better in warmer climates.

Lesson learned.

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