point taken Peter but they still make practice subjects I guess
Spring would be the best time before any drifting and when all the bees are sure to belong
point taken Peter but they still make practice subjects I guess
Spring would be the best time before any drifting and when all the bees are sure to belong
Hmmm. So what about bees that drifted in the previous autumn. And there is no drifting in the spring? I think not.
Taking them from the centre of the brood nest is the only way to be sure. Give the comb a gentle shake to remove the older bees and then take your sample from those that remain. Why do all the morphometry work if you cannot be sure that the bees came from that queen?
Best wishes
Peter
Peter Edwards
Peter.
If you take a sample from the floor and take a sample from the brood nest you will find there is a pretty good correlation.
I have also found that a colony produces a similar scattergram if sampled several times over a period of years irrespective of any seasonal drifting.
For several years now the Bibba magazine has been full of well intentioned articles about the accuracy of sampling techniques, but the elephant in the room is whether there is actually a good correlation between wing pattern and underlying DNA. If not, the arguments about sampling from the floor or from the brood nest are not that relevant.
Cart before the horse.
Wing venation will indicate a hybrid fairly clearly but it may not tell you much about whether the colony tested is pure race especially if you have been sampling wings over a period of years and using that information as part of the selection process. It is quite conceivable that you could get a scattergram with all the points in the correct quadrant which turns out to have mixed genetics.
What does produce very inaccurate results is sampling too soon after a colony has been requeened. Even after 3 months you still have bees from the previous queen present.
Last edited by Jon; 22-10-2013 at 08:38 PM.
Could be wrong but I think winter bees are laid purposefully by the queen
Any foragers or flying bees from this year will be dead by next spring (on the floor right enough)
That's why September on is so important laying wise
Drifting also depends on flow because empty handed bees are unwelcome when the turn up at the wrong door
Make sure it's not a bottle of Buckfast.
Last edited by Jon; 22-10-2013 at 10:56 PM.
[QUOTE=Jon;22146]Peter.
>Wing venation will indicate a hybrid fairly clearly but it may not tell you much about whether the colony tested is pure race especially if you have been sampling wings over a period of years and using that information as part of the selection process.
>It is quite conceivable that you could get a scattergram with all the points in the correct quadrant which turns out to have mixed genetics.
Seems to me that the first statement contradicts itself and that is re-inforced by the second.
>the elephant in the room is whether there is actually a good correlation between wing pattern and underlying DNA.
Yes - and this was something that the money from the Co-operative was supposed to resolve, but has so far failed to do - spectacularly!
However, we should perhaps remember that the Galtee group started by using wing morphometry; I seem to recall that those schoolgirls analysed 21,000 wings - and more than earned the top prize for their work.
Of course, none of us are claiming that wing morphometry is sufficient alone, but it served Galtee members well - and it would appear to have worked for me too.
Peter Edwards
[QUOTE=Peter;22152]Not at all.
Check out the Moritz paper!
Once you start using wing morphometry as part of a bee breeding programme it starts to lose its value.
Moritz recommends discarding it as a selection method or switching to a different set of morphometric variables after a few generations.
This paper is critical to understanding wing morphometry limitations.
The more it is used the less predictive it becomes.
As a snapshot of a population of bees which have never been selected, it should be quite useful.
The wing morphometry survey started about 5 or 6 years ago and the Galtee breeding programme has been going more than 20 years.However, we should perhaps remember that the Galtee group started by using wing morphometry
DNA microsatellite analysis is getting cheaper every year so this is going to make the wing morphometry redundant in the long run anyway.
Last edited by Jon; 22-10-2013 at 11:36 PM.
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