[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]

Drunk analogy (was Progress)



John Bois wrote:
>Movement away from the wall is more rapid than the aimless >meanderings of
a random walk. 

@@@It may be. The random walk is a good null hypothesis that needs to be
tested and rejected if wrong. And movement to the left will be more rapid
than in the original drunk example because evolution doesn't go back to the
wall every time to begin. Some lineages bud off a long way from the wall
before, for example, the stem lineage falls over. But do they more often
evolve to the left or right? is the central question.

>The acquisition of a radical new trait is more likely to lead you
>leftward.  For example, the attainment of language provides a >completely
novel substrate upon which natural selection can work.  >This increasing
complexity of substrates may not be progress, but >isn't it fair to call it
an engine leading some creatures away from the >wall?

@@@I agree it's possible for the attainment of radical new traits to lead
more often away from the wall than towards it (although I'm not at all
sure). Language seems like an obvious example to us. But if this is an
'engine' driving us away from the wall, it will have to be totted up
against examples of similar engines driving lineages the other way. Mass
extinction? This seems to be a pervasive engine that tends to drive whole
bunches of lineages back towards the wall. If lineages close to the wall
are more likely to persist through radical changes in environmental
conditions, then those heading towards the wall in 'normal' times might
even be said (although I would never say it, of course) unwittingly to be
making progress towards relative safety. Other engines? Simple things go
wrong less often than complicated ones? Simple things need control systems
that are easier to make and less expensive to run? Frequent abandonment of
flight on islands because it's inefficient to keep all the flight gubbins
when you don't need to migrate and there are no foxes?  

Philidor wrote:
>The progress I was looking at was the increasing ability of an
>animal or plant to survive in its circumstances. Think of the arms race
>between carnivores and herbivores

@@@Do herbivores and carnivores progress in an arms race in terms of what
you take to be progress, i.e. 'the increasing ability of an animal...to
survive in its circumstances'? Were gazelles less vulnerable to predation
when both they and cheetahs were slower? Are cheetahs more efficient
predators now that both they and gazelles are faster? Only, it seems to me,
If we equate some variable like 'faster' with 'progress', which doesn't
seem to take much into account (small, wiry, superfast cheetahs, for
example, often lose their kills to bigger, butcher predators who haven't
gone so far down the superfast road; was this so much of a problem when
both cheetahs and gazelles were slower but more solidly built?). In terms
of the ability of both predator and prey to survive and populate the
environment with their offspring, progress in your sense doesn't seem to be
happening.

@@@George: I apologise for responding personally to you yesterday. I took
your 'deplorable' response to my e-mail personally, (and 'fashionable' is
even more insulting!), but I conceed that you were attacking a particular
type of academic arm waving with which you disagree and not just my arm
waving on the subject. Sorry. (I still think you're dead wrong though!)

Hope you all make a lot of progress today.
Chris