Paul Cherubini cherubini at mindspring.com
Fri Oct 13 09:26:52 EDT 2000

Pat Foley wrote:

> Fst is a composite index of population subdivision. It does not deal 
> with all the details and does not identify and reveal the uniqueness of 
> all the small populations. Who cares about small populations? Read 
> the literature. Most modern evolutionary scientists suspect that much 
> of the future of a lineage lies in rarish events in small populations.

I am unaware of any evidence that would suggest there are 
any local, semi-isolated or isolated populations of monarch
butterflies or painted ladies in the 48 USA states.

> Do you want proof that increasing population intercommunication
> increases disease transmission and epidemics? Read the literature on
> epidemiology!

No outbreaks of any infectious diseases have been known to occur in 
wild populations of the monarch butterfly. 

> Do you want proof that random butterfly transplants confuses the
> research on butterflies? Read what the researchers have to say. Read
> Brower and Opler and Ehrlich and Hanski. Or talk to them.

Yes, we read in detail the opinion Dr's Lincoln Brower, Chip Taylor, 
Karen Oberhauser and eleven other monarch scientists about how 
coast to coast releases of monarchs could confuse attempts to look 
detect signatures of historical migrations. But none of these scientists
are population geneticists.

Earlier this year geneticist Bruce Walsh explained why even massive
transfers would not confound these types of studies: Bruce wrote:

"Of potentially greater concern for scientific studies is the impact of
transfers on studies of the genetic structure  of a populations, in
particular studies of whether apparently disjunction populations have
historically exchanged genes.    Transfers may confound such studies 
if (1) unlinked markers are used AND (2) transfers comprise a 
significant fraction of the population.  However, human geneticists 
have developed methods based on tightly linked markers (STRs 
[simple trandem arrays] linked to SNPs [single nucleotide
polymorphisms] ) that allow the age of migration events to be
ascertained.  These approaches have been used to distinguish recent 
from historical human migrations.  As a biologist, the question of 
interest in not very recent gene exchange, but rather the historical 
levels of exchange that  occurred before humans were present.  
The newer multiple linked marker methods directly address this 
issue. Thus, if one uses the more recent approaches (as would be 
required to obtain publishable results for front-line journals), even 
massive transfers would not confound these studies."

Paul Cherubini, Placerville, CA

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