Biology Reference
In-Depth Information
the anatomy of queens that results in the mixing of the sperm of her
many mates, and an extremely high genetic recombination rate. Greg
Hunt and I built the i rst genetic map for a social insect, one of the
i rst for any insect, and found that the recombination rate of the honey
bee was extremely high. It is still the highest of any animal mapped so
far. Recombination occurs when gametes (eggs and sperm) are being
made. Each gamete ultimately contains a nucleus with a single set of
chromosomes that are parts of chromosomes inherited from both
parents—they are recombined. Recombination takes place during meio-
sis when duplicated pairs of chromosomes from the mother and father
come together, break in specii c places, and reattach to form chromo-
somes that were derived from both parents (Figure 3.4). h e frequency
of breaking and recombining along a chromosome is called its recom-
bination rate. h e farther apart two parts of a chromosome are, the
more likely it is that there will be recombination between them. Honey
X
F1 Queen
Egg Gametes
Figure 3.4.
Recombination in a hybrid queen. A single chromosome is
represented in this illustration. A queen from a “light gray” line was crossed to a
haploid male from a “dark gray” line. h ey produced an F1 hybrid queen with
one light gray and one dark gray chromosome. During oogenesis, the production
of egg gametes, meiosis occurred where the chromosomes were broken and
reassembled into a single chromosome that went into the egg.
