Re: Mass Extinction Statistics

[John Bois <jbois@umd5.umd.edu>]

On Thu, 24 May 2001, David Marjanovic wrote:

> > I put up 500,000 black dots and 500,000 red dots on my board.  I have a
> > cannon that fires 500,000 bullets at once.
> 
> I'd rather say you have a big bomb rather than exactly 500,000 individual
> bullets. You let the bomb detonate, and then you look if you find a pattern
> among the unhit dots.

Well, whatever the delivery mechanism, it should have a random
effect--perhaps more diffuse than a bomb--after all, the placentals are
not all living together in one happy bunker, nor the marsupials.  There
are millions (probably) of organisms in many niches.

> > Given our assumption of equal population number, equal
> > susceptibility, etc., is this not a fair analogy?  And isn't it true that
> > the more dots I have, the greater my chance of reaching 50/50?
> 
> The more times you fire the cannon, not the more dots you have.

Several have said this.  Why?  What's the difference whether I increase
the population or the number of bolide strikes?  Flipping a
flippin' coin a hundred times is the same as flipping 100 flippin' coins
once.