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Rosie
04-02-2014, 07:06 PM
I recently heard a fascinating account of the genetic make-up of Europeans which, I think, might be pertinent to bee breeding. I know I am thin ice here but I would be grateful if the geneticists amongst us would try to follow my logic and comment.

According to this programme Homo sapiens were closely enough related to Neandethals to interbreed. I always thought that the ability to interbreed and produce fertile offspring was an indication that the two individuals were of the same species. A horse and a donkey can interbreed and so can a lion and a tiger but in both cases the offspring are infertile. However, according to the radio programme this principle is not clear-cut and there can be degrees of fertility in the offspring which indicates the closeness of the 2 species of parents. Apparently those of us with certain Neanderthal genes are less fertile than pure Homo sapiens. These days we have up to 6% Neanderthal in us but this was formerly much higher. Over the generations those with the most Neanderthal have been less successful (fertile) than others and so the Neanderthal genes in the population is slowly declining.

Now we come to bees. I recently read a report on a study of pure carniolans and pure Amm bees in Poland. They allowed virgins of each race to fly in areas where the drones were pure but mixed. When they studied the genetic make-up of the next generation they found that the carniolan queens were laying mixed-race eggs but the Amms were laying pure Amm eggs. Hence they concluded that the bees were somehow being selective. This has been witnessed here, admittedly not in scientific studies, and all sorts of isolation mechanisms have been dreamed up for this such as apiary vicinity mating, cold weather mating etc. If my memory serves me correctly I think the Polish researchers guessed that it could be a mechanical thing such as genetalia sizes. I will not enlarge on that but it seems size does matter and smaller is sometimes better.

Additionally there seems to be a lot of talk about reasons why much of the sperm found in spermatheca is dead these days and people are guessing it's to do with varroacides.

Could it be due to the fact that queens of certain races are unable to support the sperm of foreign drones once deposited in their spermatheca? Perhaps carniolan queens can keep the sperm of Amm alive but Amm queens can't keep carniolan sperm alive. All this could be due to the fact that the two races are almost different species. They have probably been separated for millions of years, perhaps far longer than the separation of Homo sapiens and Neanderthals (whatever species Neanderthals are).

It means that in a mixed population some races are more successful than others because so much of the sperm in their spermatheca is alive. Other race queens are quickly superseded because they start with fewer viable sperm due to the fact that many of them are dead or useless but occupying valuable space. If this lot is true all sorts of breeding strategies can be worked out from it.

Is this another of my mad ideas or has it got legs? Are the PC police on their way?

mbc
04-02-2014, 07:51 PM
I recently heard a fascinating account of the genetic make-up of Europeans which, I think, might be pertinent to bee breeding. I know I am thin ice here but I would be grateful if the geneticists amongst us would try to follow my logic and comment.

According to this programme Homo sapiens were closely enough related to Neandethals to interbreed. I always thought that the ability to interbreed and produce fertile offspring was an indication that the two individuals were of the same species. A horse and a donkey can interbreed and so can a lion and a tiger but in both cases the offspring are infertile. However, according to the radio programme this principle is not clear-cut and there can be degrees of fertility in the offspring which indicates the closeness of the 2 species of parents. Apparently those of us with certain Neanderthal genes are less fertile than pure Homo sapiens. These days we have up to 6% Neanderthal in us but this was formerly much higher. Over the generations those with the most Neanderthal have been less successful (fertile) than others and so the Neanderthal genes in the population is slowly declining.

Now we come to bees. I recently read a report on a study of pure carniolans and pure Amm bees in Poland. They allowed virgins of each race to fly in areas where the drones were pure but mixed. When they studied the genetic make-up of the next generation they found that the carniolan queens were laying mixed-race eggs but the Amms were laying pure Amm eggs. Hence they concluded that the bees were somehow being selective. This has been witnessed here, admittedly not in scientific studies, and all sorts of isolation mechanisms have been dreamed up for this such as apiary vicinity mating, cold weather mating etc. If my memory serves me correctly I think the Polish researchers guessed that it could be a mechanical thing such as genetalia sizes. I will not enlarge on that but it seems size does matter and smaller is sometimes better.

Additionally there seems to be a lot of talk about reasons why much of the sperm found in spermatheca is dead these days and people are guessing it's to do with varroacides.

Could it be due to the fact that queens of certain races are unable to support the sperm of foreign drones once deposited in their spermatheca? Perhaps carniolan queens can keep the sperm of Amm alive but Amm queens can't keep carniolan sperm alive. All this could be due to the fact that the two races are almost different species. They have probably been separated for millions of years, perhaps far longer than the separation of Homo sapiens and Neanderthals (whatever species Neanderthals are).

It means that in a mixed population some races are more successful than others because so much of the sperm in their spermatheca is alive. Other race queens are quickly superseded because they start with fewer viable sperm due to the fact that many of them are dead or useless but occupying valuable space. If this lot is true all sorts of breeding strategies can be worked out from it.

Is this another of my mad ideas or has it got legs? Are the PC police on their way?

Could it be that heavy boned people with low sloping foreheads and low intelligence may find it harder to find willing partners to successfully raise families with ?

Rosie
04-02-2014, 08:05 PM
Thre's no accounting for taste mbc. Perhaps Amms think that swarmiolans are ugly. According to the programme though the problem was fertility rather than attractiveness.

mbc
04-02-2014, 09:01 PM
Ahh ! You've seen the family album then !
lol.
Smacks of creationism rather than evolution to me.
Nice idea with the variable sperm survive-ability in the spermatheteca, but as we can send sperms all over the world with little loss in viability I dont buy it.
I personally think strains can remain remarkably pure under heavy pressure simply because a proportion of each population will always prefer to mate with like. This fits in with bell curves which elegantly explain most things we see in biological systems.

Rosie
04-02-2014, 09:36 PM
I know fastbuck sperm and pseudo carniolan sperm has been shipped around and it's usually beeen used to inseminate Italians but I know of no instances of inseminating Amms with other races. The whole point is that you can put Amm sperm into a carniolan queen but you can't successfully put carniolan sperm into Amm queens. I can't imagine why anyone woud want to do the latter but if someone is then it will blow my theory out of the water.

Beefever
05-02-2014, 08:58 AM
Rosie. I’m sure I’ve read something about the study you refer to. I’m afraid I didn’t give it much more though as my immediate reasoning was that if it were true then why isn’t this nation dominated by pure AMM and why are isolated mating sites necessary?

Rosie
05-02-2014, 09:59 AM
Hi Beefever. Thanks fo your thoughts on this. The study only covered carniolans and I supect most of the imports to the Uk have been Italians. However, I would turn your question on its head and ask why there is still so much Amm genetics in the UK and Ireland after such massive imports over such a long time.

Beefever
05-02-2014, 12:10 PM
Yes I understand your reasoning on this. Pre-varroa, it could be argued, any swarms that escaped were more likely to survive in our climate if they were AMM type so providing many of their drones at a DCA. But of course this can’t be said now. Another argument in favour of your thinking is that Africanised bees in USA seem to dominate wherever they go but I think this is more to do with the amorous nature of their drones. So it can’t be down to numbers or else they would have been diluted long ago.
I still keep coming back to the fact that I find it harder and harder to keep an AMM type bee in my hives. So in this narrow view of my own experience, I don't see how it works.

Rosie
05-02-2014, 12:43 PM
I still keep coming back to the fact that I find it harder and harder to keep an AMM type bee in my hives. So in this narrow view of my own experience, I don't see how it works.

I must admit I find my own black bees keep turning yellow but then I doubt if my bees aren't absolutely pure to start off with and yellow, of course, is an Italian trait and not carniolan. Even if the theory is right I would not expect it to work 100% but just enough to skew the odds in favour of Amm remaining more pure than statistics alone would predict.

I still think it's a fascinating concept though that subspecies diverge gradually until they eventually become different species and so does their breeding compatibility. I had always assumed that species could either interbreed or not but on reflection there must degrees of compatibility and it would not be surprising to find that honey bee sub-species fall into this grey area.

The Drone Ranger
05-02-2014, 12:56 PM
Hi Beefever. Thanks fo your thoughts on this. The study only covered carniolans and I supect most of the imports to the Uk have been Italians. However, I would turn your question on its head and ask why there is still so much Amm genetics in the UK and Ireland after such massive imports over such a long time.
Hi Rosie
It's also the case that large quantities of AMM bees were imported at various times
French Amm had a bit of a reputation for temper

Just wanted to add that my own bees have a tendency to become more black
That must be the local drone population although I catch the odd swarm like last season which were very yellow

wee willy
05-02-2014, 04:56 PM
I think this is more to do with the amorous nature of their drones. So it can’t be down to numbers or else they would have been diluted long ago.
.

I understand the 'African queens' emerge 1/2 days earlier than other species ,giving them the edge ?
VM


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The Drone Ranger
05-02-2014, 05:13 PM
I understand the 'African queens' emerge 1/2 days earlier than other species ,giving them the edge ?
VM


Sent from my iPad using Tapatalk

A bit of grafting and knock off the queen cells should fix that
The drone population is not easy to sort out
Feral colonies with Africanised bees are not so easily taken out by varroa so they have the genetic edge
It's a steady march North by the drones :)

Little_John
02-03-2014, 04:48 PM
Hi Beefever. Thanks fo your thoughts on this. The study only covered carniolans and I supect most of the imports to the Uk have been Italians. However, I would turn your question on its head and ask why there is still so much Amm genetics in the UK and Ireland after such massive imports over such a long time.

Your thesis is intriguing - maybe there is something to that ...

For now, my money would be on our weather: short, sudden mating windows; more willing, cooler flying drones; that kind of thing. Nothing in the way of research to back that up, afaik, but I've heard this kind of thinking expressed many times over the years. Maybe mediterranean drones need an all-over suntan before they'll get off their arses ? It's certainly true of many of the blokes I've met from that part of the world. :)
LJ

Just stumbled across:
Genetic differentiation and hybridization in the honeybee (Apis mellifera L.) in Switzerland. Gabriele Soland-Reckeweg

"Some subspecies are particularly interesting for apiculture and have replaced indigenous subspecies in large parts of their native distribution areas. In Europe, the formerly most widely distributed subspecies used to be the A. m. mellifera, or black honeybee. Its population has declined and became fragmented by introductions of subspecies from south-eastern Europe."

"In the present study, microsatellites were used to assess the impact of sympatric occurrence and conservational breeding programs on the amount of hybridization and to quantify the proportion of dispersers in male honeybees (drones). The results showed that an increased amount of hybridization could be assigned to sympatric occurrence, but nevertheless the last remaining population of the alpine ecotype in the breeding populations is significantly differentiated from the breeding populations of introduced subspecies despite decades of honeybee imports. " (which is pretty-much what you're saying ...)

"Besides the impact of breeding management on the reduction of hybrid proportions, a natural hybridization barrier due to a reduced fitness of male hybrids seems to be involved. " (so this gene conservation phenomenon could well be due to not-up-to-snuff hybrid drones then ?) They miss the sun :)