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Re: Re. Progress

is there an example of a multi-celled organism type reverting back to
single-cell organism type?

Logically and statistcally, if such complex-to-basal reversions were
commonly occuring we'd have beaucoup bunches of types of single-celled
organisms that used to be multis.  The length of time that single-cell
organisms have been around is just about the longest span of any extant
organism so they'd have more chances to create multis that could revert
back to singles.  

So MOST extant single cell organisms should be found to be reversions
from multicelled -yes?   

That would be the case due to simple math projections based on the
assumption that single- and multi- have an equal chance at survival.  Is
it the case?


chris lavers wrote:
> ...I should add to my last e-mail, before someone cottons on to the wrong
> end of the stick, that each right or left stagger of the drunk in the
> example corresponds to a lineage evolving towards increased or decreased
> complexity *by the process of natural selection*. If lineages move as often
> towards 'reduced complexity' as towards 'increased complexity' then the
> idea of large scale progress in the evolution of life is seriously
> compromised. Assuming for the sake of argument that this is the case (I
> don't, except in the sense that null hypotheses have to be refuted before
> alternatives can seriously be considered), then we might talk of lineages
> 'making progress' towards increased complexity, but then we should also
> talk of other lineages 'making progress' towards decreased complexity. With
> no overall direction, 'progress' in this sense just reduces to 'change' -
> change by the process of natural selection in response to circumstance.
> IMHO, change is the better word because it is neutral.

Flying Goat Graphics
(Society of Vertebrate Paleontology member)