Hi,
> >> With whom does the queen mate? OK, I know she mates with a drone, but =
> >> is it a drone from her own hive?
Drones are usually prevented from gaining acess to the
queen within the hive shortly before her mating flight by workers.
However, it remains possible that the queen will meet and mate
with drone(s) from her own hive whilst on her mating flight, but this
will depend upon the number of other drones present (if mating is
truely random and no kin discrimination is shown) from other hives.
> > This is not desirable, as it would be her brother.
I suspect it would actually be her son. However, yes it would be
undesirable. In addition to inbreeding supression (reduced fecundity
etc) her son will carry one of her two sex alleles. That is if
she ONLY mated to her son half of the fertilised eggs laid
(intended workers normally) would start to develop as diploid males.
In apis mellifera where the cells are capped late in larval
development the response of the workers is to kill and eat these
males, so ther cost to the hive is limited in the sense that little
nutitrional, or cell or time waste occurs, but however note that her
fecundity is essentially halved and so she will produce less workers
per unit time, and over her life time. This is a serious cost and
may well lead to this hive failing to establish in competition from
other hives. Of course the actual cost will depend upon the number of
other non-related matings she gets, but the principal holds.
>
> >My understanding is that she needs to mate 12-15 times to have a long life.
I am not aware of any evidence that multiple mating actually directly
increases her longeivity. Rather she probably multiply mates for at
least two simplistic reasons, but note there must be other factors at
work here as neither of these explainations would account for so many
matings (queens excude sperm and thus have tacken on too much (see
a), and to sample the population sex allele at random to reduce
matched matings and hence diploid male production would only require
some 6-10 matings (see b)
(a) compared to a single mating, to ensure she acquires sufficient
sperm to last her lifetime. That is to avoid being sperm limited. A
queen that runs out of sperm can no longer lay diploid eggs (workers
or queens) but is committed to laying only drones.
(b) to reduce the risk of mating to a sex allele related male (e.g.
son, see above) and thus increase her overall worker production and
minimise diploid male production. (Thus in other species , such as
the Meliponia bees, where the cells are capped early on, and so
workers cannot kill diploid males and eat them, and so the cost is
higher, workers kill and usurp the queen if she produces diploid
males and so these queens rarely multiply mate as reducing the
diploid load (simplistically, the ratio of workers that develop as
diploid males) from 50% to say 12.5% will not increase her chances
of avoiding usurping, but the extra matings will increase her chance
of mating to a sex allele related male).
However, since an Apis mellifera queen that is sperm limited is
likely to be usurped in that the workers will try to rear a queen and
swarm, and that a match-mated (son mated) queen may well fail to
establish a successful hive (colony), then indirectly, yes, it will
effect her longeivity.
> Does a queen actually mate that many times? I thought the normal was four
> to six times in only one flight.
There is observational evidence for some 17-37 copulations per
mating flight, and perhaps up to 5 mating flights. However recent
molecular analysis to ascribe paternity to the workers in the hive
has also established that in known single queen hives the queen is
using sperm from at least 17 males, and so must have acqrued at
least that many copulations during her mating flight(s).
Rob
Robert Butcher,
Evolutionary and Ecological Entomology Unit,
Department of Biological Sciences,
Dundee University,
Dundee, DD1 4HN,
Tayside, Scotland,
UK.
Work Phone:- 01382-344291 (Office), 01382-344756 (Lab).
Fax:- 01382-344864
e-mail:- [log in to unmask]
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