Biology Reference
In-Depth Information
tar with lower sugar concentration. Newly emerged high-backcross
workers with fewer ovarioles had higher expression of
HR46,
consistent
with the pattern we saw in the expression study of highs and lows.
h ere was no association of
PDK1
and ovary size in newly emerged
bees, consistent with what we found in the expression studies. In forag-
ers,
PDK1
was expressed more in bees with more ovarioles, as we found
with high- and low-strain comparisons. h ese results demonstrated a
genetic correlation in adult bees among
PDK1, HR46,
ovariole number,
and foraging behavior.
HR46
probably acts early, perhaps on ovaries
during larval development, and
PDK1
acts later, perhaps in response to
dif erential signals from the ovaries.
6.8 Caveat
Genomics is still in an infant stage. h e genome is hugely complex and
interactive. Too ot en we try to reduce it to “a gene for X” when it clearly
doesn't work that way. We have not yet i gured out how to incorporate
a view of the genome as part of the ecology of the gene, where the ex-
pression of genes and gene regulatory networks of the entire genome,
combined with the internal physiology and external environment of
the organism, are part of the ef ect of an individual gene. In Section 6.7,
I presented one piece of what we think we know about the genomics of
foraging behavior. I have not presented more because I am certain that
what we think we know today will be wrong tomorrow, and then this
topic will already be out of date.
Suggested Reading
Amdam, G. V., Ihle, K. E., and Page, R. E. 2009. Regulation of honeybee worker
(Apis mellifera)
life histories by vitellogenin. In
Hormones, Brain and
Behavior,
2nd ed., vol. 2, ed. D. W. Pfaf , A. P. Arnold, A. M. Etgen, S. E.
Fahrbach, et al. San Diego: Academic Press, pp. 1003-1025.
Amdam, G. V., Nilsen, K. A., Norberg, K., Fondrk, M. K., et al. 2007. Variation in
endocrine signaling underlies variation in social life history.
Am. Nat.
170:37-46.
Amdam, G. V., and Omholt, S. W. 2003. h e hive bee to forager transition in
honeybee colonies: h e double repressor hypothesis.
J. h eor. Biol.
223:451-464.
