>Let's keep critique reasonable, shall we?  The comments offered seem far

> less than a substantive critique.


In any trial that I run, I collect a Timepoint Zero data set to confirm
that the test and control groups start essentially equally.  While I do not
question that there were differences in gene expression at the end of the
trial, I have no way of knowing whether those differences existed at the
start of the trial.

>However, a variety of different agrochemicals had been applied to these
fields before and during the 2010–2011 time period when the feeding trials
were conducted. The probability of exposure to these chemicals was the same
for C and IE hives.

The last sentence above is a strong assumption, certainly not supported by
the data from the Fraziers, who have pointed out that even side-by-side
hives can exhibit vastly different exposure to pesticides due to their
foragers foraging in different areas.  IMHO, the fact that these hives were
placed in different woodlots, and surrounded by crops treated with a wide
variety of pesticides means that we have no way of knowing if the tiny bit
of imidacloprid fed to the test hives had anything to do with the observed
differences in gene expression.

If anyone has information that these variables were actually controlled for
in this experiment, please correct me!

If I were to go out to two apiaries of my own hives placed in woodlots
separated by 100 meters and look at the drawers of the pollen traps, I
would bet that the pollen contents of those drawers will often be vastly
different.  And if that pollen contains pesticide residues, it is likely
that the pesticide exposure to each of those colonies (or groups of
colonies) will be different.

To then go and conclude that gene regulation of those two groups of
colonies differs because of giving one group a minuscule dose of one
particular additional pesticide seems like a stretch to me.

I am very interested in the effects of pesticide exposure upon gene
expression.  But I am not comfortable drawing conclusions from this trial
due to the likelihood of there being major variables that were unaccounted
for.
-- 
Randy Oliver
Grass Valley, CA
www.ScientificBeekeeping.com

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