Artficial Insemination - viability?

[Little_John]

The Kraus paper is basically confirming that the most fit drones belonging to the dominant colonies get the girl.

What they saying is that they haven't a clue how colony 'fitness' - thus which drones will get to mate - is determined:

We found clear evidence for an extensive diversity in
male mating success at the colony level. Some colonies
had significantly more matings (about an order of
magnitude) than other drone producing colonies in the
same year. This is remarkable, because we had taken
great care to standardize conditions for the drone
producing colonies. All drone mothers were sister
queens, all host colonies were of equal size and all had
similar numbers of drones in the colony (two covered
frames).

In our experiment the ‘fit’ colonies seem to have
produced males which not only out-competed males
from other colonies in mating, but also were more
successful in post-mating competition. The fit colonies
produced drones with a higher reproductive success than
those of the other, less successful colonies. We do not
know which effect caused the increased success of drones
from specific colonies.

Although the actual mechanism for this post-mating
selection in our study must remain open, this is to our
knowledge the first evidence for differences in the male
reproductive success for honeybees in a natural mating
situation.

LJ

[Little_John]

BTW - I found a 1994 paper by a bloke called Coelho about the flight characteristics of drones in relation to mating. I found it to be a fairly dull read to be honest, all about fuel capacity, flight duration, load-carrying capacity and so on ... I think the bloke must have been an aeronautical engineer in a former life.

There was one little snippet though which I though worth passing on - explaining why some queens fall out of the sky and some don't - maybe that's obvious to some, but this guy has actually mathematically calculated why this happens.

Essentially, it's down to why drones are so big in the first place. They need to be in order to have the strength (not speed !) to carry the queen as well as themselves during aerial mating. But the queen, being smaller, does not have the load-carrying capacity of the drone. So - if there is a clean breakaway after mating, the queen can fly on to mate with another drone - BUT - if the breakaway is not clean and the paralysed/dying drone stays connected, then the queen cannot support both of their weights and the pair fall to the ground. Simples.

LJ

[mbc]

IMHO queens choose drones, not the other way round, though she can only choose from those who reach her.

[Castor]

Thanks for your thoughts Team - my simplistic ideas about *improving* a line by II have been dashed. It strikes me that with care we could *maintain* a line, but due to the drone fitness issue there's significant doubt about *improving* it, and a significant chance of degrading it.

I need a ponder.....

[prakel]

So - if there is a clean breakaway after mating, the queen can fly on to mate with another drone - BUT - if the breakaway is not clean and the paralysed/dying drone stays connected, then the queen cannot support both of their weights and the pair fall to the ground. Simples.

LJ

Interesting sounding paper, at least it's looked at the process.

My question here is, where does the business of queens returning to the hive with the so called mating-sign fit in? Not a clean breakaway in the air, so, has she chewed the bulk of the drone away and then returned to the hive for further assistance?

Commonly held view we often see repeated is that returning with this sign is the norm. I doubt that, personally, based on a general lack of observation of it over the years but assuming that the majority are right and I'm wrong, how do queens get around this when multi-mating on a single flight? Could it be a cause of early queen failure, the queen forced to return home early and then for whatever reason failing to fly again.

[Little_John]

Interesting sounding paper, at least it's looked at the process.

Well, not exactly - he's determined this outcome from previous load-carrying calculations.

If you want a copy of the paper- let me have an email address in a PM, and I'll send it to you. Unfortunately, it's not in a nice compact .pdf format - 'cause they wanted money for that - so I grabbed the info as four .jpg's instead - that's a total of 1 Mb.
I've tried uploading 'em as attachments here, but the system reduces them to 80-odd k each, which won't be very readable.

'best, LJ

[Jon]

Gavin can stick stuff on the server if you contact him as long as it is not a major copyright issue.

Edit - probably is though if they wanted money for it!

[Little_John]

Hello Jon - I've just re-traced my steps regarding the source - which is:
http://www.academia.edu/836032/The_f...tion_to_mating

If you try to download the .pdf, you're required to log in, with password etc - so I assume there's a subscription involved - but when I hit my browser's back button, much to my surprise the paper appeared anyway, as 'greyed-out' .jpg's within an .html formatted page, with a 'pop-over' window which nags you again to register and log-in. BUT - this page (complete with pop-over) can simply be saved 'as is' - .jpg's and all. At least it can with Firefox 1.5 running under Windows 98 (don't laugh ...).

Then simply extract the .jpg's from the /files sub-directory - they're each 400-500 k at this point with 256 colours - reduce 'em to 16 colours (I use IrfanView) and they're then 250k each and quite readable. As for copyright - really couldn't say.

LJ

[gavin]

Thankfully (phew!) the paper is quite readable straight from the link with modern software .

G.

[Little_John]

So - nobody else on here with a coal-fired steam-driven computer then ?
LJ