# Genetic Bottleneck?



## longshotgene (Jan 3, 2014)

I have a question for the scientific minded out there? I know from a genetic standpoint, one can create a genetic bottleneck by crossbreeding the same genetics over and over. In effect, you can create what you think is genetically pure, but in reality, you have produced something with very weak genetics. Is it possible with the limited gene pool every country is dealing with, that we are in effect bringing the diseases that are appearing on ourselves? What research has been done on these diseases having existed prior to the recent outbreaks? The Africanized bees are a recent addition to the gene pool. What has been their history in relation to fighting these new diseases that are hitting? Are they affected?


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## jrbbees (Apr 4, 2010)

No we are importing every disease and pest from around the world into the USA. That way we spend all the money on research, treatment and prevention. Then treatments can be produced back in the country of origin without the expense of research, testing and development. They will then have a solution for their local problem at great savings.

There is the very real question if some foreign countries are bring in pests and organisms with that purpose in mind.


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## deknow (Jul 17, 2006)

Houscats can all be traced to a single female ancestor. Bottlenecks are how evolution happens.
If housecats were narrowed to a single female ancestor with scientists watching, it would be predicted that they would soon be wiped out.

Deknow


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## Michael Bush (Aug 2, 2002)

>Is it possible with the limited gene pool every country is dealing with, that we are in effect bringing the diseases that are appearing on ourselves?

Several of the leading bee scientists have suggested that.>Is it possible with the limited gene pool every country is dealing with, that we are in effect bringing the diseases that are appearing on ourselves?

Several of the leading bee scientists have suggested that.

> What research has been done on these diseases having existed prior to the recent outbreaks?

What can be. Old samples are examined for what we have now found. So far we keep finding Nosema cerana in whatever samples can be found no matter how old... there is much interest in pinpointing when it arrived.

> The Africanized bees are a recent addition to the gene pool. What has been their history in relation to fighting these new diseases that are hitting? Are they affected? 

The appear mostly unaffected.


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## Dominic (Jul 12, 2013)

longshotgene said:


> I have a question for the scientific minded out there? I know from a genetic standpoint, one can create a genetic bottleneck by crossbreeding the same genetics over and over. In effect, you can create what you think is genetically pure, but in reality, you have produced something with very weak genetics. Is it possible with the limited gene pool every country is dealing with, that we are in effect bringing the diseases that are appearing on ourselves? What research has been done on these diseases having existed prior to the recent outbreaks? The Africanized bees are a recent addition to the gene pool. What has been their history in relation to fighting these new diseases that are hitting? Are they affected?


Inbreeding does not in any way weaken the genes. It just weakens their expression. Inbreeding deperession does not come from the fact that the good genes aren't as weak, but from the fact that weak genes get expressed more and that part of the good gene combinations are lost.

Genetics is about the individual genes and their assemblage. Some genes work great when paired with multiple copies of themselves. Some genes work great when paired with different genes. Some genes, on the other hand, are only ever great at being awful. As such, even if you have a bee which expresses poor performances, that does not mean that its genetics are necessarily bad. It could just be a result of inbreeding depression in what would otherwise remain a great specimen for breeding.



deknow said:


> Houscats can all be traced to a single female ancestor. Bottlenecks are how evolution happens.
> If housecats were narrowed to a single female ancestor with scientists watching, it would be predicted that they would soon be wiped out.
> 
> Deknow


Same thing for humans, and probably all species. It's called the concept of mitochondrial Eve. We also all came from the same male: y-chromosome Adam.

Limited genetic diversity is not a guarantee of failure, despite greater genetic diversity being a factor of species fitness and capacity to adapt.


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## TalonRedding (Jul 19, 2013)

Genetic bottlenecks can and do occur in many ways. For instance, natural disaster can displace a small portion of individuals resulting in a bottleneck, emigration of a few individuals from the main population could result in a bottleneck, rampant disease and wars could cause bottlenecks. When settlers brought bees over from Europe, that could be considered a bottleneck in and of itself.
However, bottlenecks can also bring about speciation after a given amount of time. This is where the subject of "breeds" and "lines" come in. Who's to say that mellifera mellifera actually remained as such after they were isolated from the main population? I do not have an inkling as to how long it would take for speciation in honeybees to occur, but it's only a thought.
Has a bottleneck occurred? I believe it has, and many weaker traits are being expressed as a result. I imagine one could make a stack of PR literature from the floor to the ceiling that would support the claim. 
Is the bottleneck to blame for ALL the problems. I don't think so. Just my opinion.


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## WBVC (Apr 25, 2013)

What exactly do you mean by a genetic bottleneck?


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## Fusion_power (Jan 14, 2005)

> I do not have an inkling as to how long it would take for speciation in honeybees to occur


Ancestors of western honeybees spread from Southeast Asia at least a few million years ago and moved into Africa. Desertification in the Arabian peninsula then isolated the population. A few ice ages came and went pushing the bees back into Africa several times. About 10,000 years ago, the last ice age ended and honeybees spread around the Mediterranean on the east and to the west across the Straits of Gibralter differentiating into 4 branches as they spread. In the course of spreading, they produced 28 recognized geographic subspecies which can be assigned to one of the 4 main branches based on traits. Long story short, after 10,000 years, honeybees are still able to interbreed with their cousins from other branches even though they have been isolated from each other for at least 10,000 years. Western honeybees are not capable of breeding with any branch of Apis Cerana (thought to have 50 or more good geographic species) after at least 2 million years of isolation. Other work with similar types of insects indicate that speciation occurs after about 100,000 years of reproductive isolation.

It is important to recognize the distinction in the above that a geographic subspecies is NOT a reproductively separate species. All 28 geographic western honeybee subspecies are capable of interbreeding though there are some adaptations that reduce the likelihood in a few cases.


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## marshmasterpat (Jun 26, 2013)

I wonder if genetics has anything to do with the issues at all. It is often easiest to blame something more sinister or complicated to understand. But could it be habitat or perhaps the lack of habitat. 

Take a look at the urban spread that is occurring. Out here, it is St. Augustine grass for acres (likely square miles as you near Houston). Folks talk about all the forage that is there in the urban settings have likely never walked in a actual real prairie. Flowering forbs are overwhelming with the diversity of species on a SQUARE METER as great as most urban yards can brag on. Yea there is the neighbor (if your lucky - in my case individual yards) that are covered with flowering plants and the bees win with a great forage producer. But all around are St. Augustine or other exotic grasses treated with weed and feed to suppress the weeds (AKA flowering plants bees once foraged on). Now we have bees that are often foraging for 95% one agriculture crop that might have been treated with things that are potentially dangerous to the species. 

Now step into the agriculture realm. Improved pastures are frequently exotic grasses planted on fields that were disked to remove the undesirable species (AKA flowering native forbs) and sometimes treated with selective herbicides to keep the weeds out. Agriculture production is many areas is road edge to road edge single crop plantings for large acreage. 

I am not saying that modern lawn practices and agriculture are the issue. However, most species do not do well when forced to feed on one type or a limited forage range. Find a county that has not sprayed ditches with herbicides or mowed regularly and you find great diversity of flowering plants. 

Go to one of the prairie sites and the number of bugs (not just bees) foraging is crazy. Leopold said the hum of bugs collecting pollen made it hard to concentrate. And that was 80+ years ago. 

But yet there are a few folks around that have bees that are doing fine. I would have to say that points to other issues besides genetics. 

Sorry Barry if yall think I hijacked this thread. Been reading too much of the scientific beekeeper maybe.


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## TalonRedding (Jul 19, 2013)

I think habitat loss can have its place in this thread. It too can create a bottleneck.
There was a thread that hit on the topic of poor bee habitat. It had some good posts, but I haven't been able to find it.
There are a lot of factors that come into play when it comes to all the losses we hear about. Mites, insecticides, lack of habitat, some bottle necking, beekeeper error, hive beetles, wax moths, IAPV, both foul broods (which is in all hives), nosema ( which is also in all hives), natural losses, poorly mated queens, too much interruption of the hive, monoculture in certain locations, that's just to name a few off the top of my head. 
But, back to genetic bottleneck: in my opinion it is only part of the problem.


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## longshotgene (Jan 3, 2014)

Marshmasterpat, I think you have a good point with habitation loss. My wife studies the monarch butterfly. Let's talk about a dying species. In Mexico, they are practicing unrestricted de-forestation, which is elminating the monarch breeding habitat. That is a migratory species though. Unless you are talking about packages coming from down south or out west, we have to look at the immediate environment. What HAS changed? Where I live, it is largely unchanged except for the city slickers coming out to find a piece of the country. Other than that, it is technology of the beans, corn and other crops. Pesticides have changed as well. As far as bees go, what has changed? If we compare our little friends to humans, we know that humans as a whole have been way over chemicalized with antibiotics and other chemicals. As a result, we are producing the undesired side effect of selection in the bugs we are trying to wipe out. This furthers our exploration for newer drugs to wipe out these super bugs. Could it be this way perhaps with the bees? I would like to hear any word from the individuals who raise bees. Are they given a lot of chemicals so you can increase the abundance, thus leading to a bigger sale each year? Also, as for breeding, are we breeding the aggressive traits out of our stock to help not be stung as much? When you inbreed, you do create a stock with a weak immune system. These factors have to add up to something.


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## WLC (Feb 7, 2010)

In my opinion, the current bottlenecking has occurred for some very basic reasons:

First, there are 700-500 breeder queens, and they may, for the most part, be too hybridized. They're too similar to each other genetically.

Normally, you expect to get hybrid vigor when producing hybrids. However, if they're already hybridized, some studies suggest that the resulting crosses are less fit.

That's how you can get bottlenecking when breeding. Your crosses won't exhibit hybrid vigor (increased fitness).

Someone has mentioned Susan Cobey's Instrumental Insemination work elsewhere, and I do recall that a new drone sperm repository is being developed.

That's where you can get new breeder queen stocks (hopefully) without the excessive hybridization problems.


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## Dominic (Jul 12, 2013)

WLC said:


> In my opinion, the current bottlenecking has occurred for some very basic reasons:
> 
> First, there are 700-500 breeder queens, and they may, for the most part, be too hybridized. They're too similar to each other genetically.
> 
> ...


Hybridization is not guaranteed to yield poor results, it's just more complex to handle. Your best colonies, if used as mother colonies, are not guaranteed to yield you good queens with good genetics. Genes are like building blocks, and their assemblage is like engineering. If the engineering is great, you can still have a great bridge despite the otherwise bad building blocks. It might wear quickly, it might not support a lot of weight, but if all you want is to walk on it and need it quick, it might just be the perfect cheap bridge that can be built in a snap. That's hybrid vigor. On the other hand, you can have the best building materials, but a crappy engineer, and end up with the bridge collapsing and all of the resources invested in it will just end up at the bottom of the river. That's inbreeding. But even if great engineering can mask second-rate materials, it's not because you see an engineering piece of art that the interiors are rotten. Just as you don't know that they are good, you don't know that they aren't either. That's the problem with hybrids. The exterior is not representative of the interior.

In the end, many "races" thought to be pure were later found out to be hybrids (such as Iris versicolor) or maintained by hybrids (grey wolves and coyotes). Various breeds are obtained from hybridization, like the buckfast bee in beekeeping, or a number of dog races, like the German shepherds that all stem from the one same wolfdog. Breeding hybrids with hybrids continuously can yield good results on the long run as long if rigorous, but F2-FX are likely to yield uninteresting results. New breeds take a while to develop.


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## grozzie2 (Jun 3, 2011)

WLC said:


> First, there are 700-500 breeder queens


I find that really hard to believe. Just reading here on beesource, there are _at least_ a hundred different folks doing a small handful of queens. Surely they aren't all using the same mother queen sources.

I think a lot of folks just assume, because large commercial operations source from large commercial queen raising operations, there are a limited number of mother queens used for breeding, but, that's only for the large scale replacements in hives that are managed such, they never get a chance to breed anyways. From a genetic point of view, those are all dead end hives to begin with, they wont be propogating to a successor generation. But there are hundreds, probably thousands, of small time folks that are not buying queens, instead raising a few here, and a few there.

If you exclude the massive population of hives that wont be permitted to breed, and look only at those that are going to produce offspring, but count every back yard and sideline operation doing exactly that, there is no bottleneck visible for honeybees, no shortage of mother queens providing open mated daughters. Use my own example, we started with 2 queens from australia, later added 2 procured locally. All of them are long gone, the queens in our hives are anywhere from 2nd to 4th follow on generation, all open mated. I know of other folks just up the road from us, haven't brought in a queen for 10+ years, yet have 30 hives going strong. Then there are a few that brought in queens from california, and some with queens from hawaii. Plenty of opportunity for drones from all of those sources to mix it up in the DCA's in our area.

How is this creating a bottleneck? 

I think the only folks that see a potential bottleneck developing, are those that for some strange reason believe you must buy mated queens from large scale queen producers to requeen a hive. But the reality is, they dont matter, they are creating genetic dead ends, those bees wont be producing daughter queens anyways. But as long as there are folks not buying into that mantra, be it for philosophical reasons, or financial reasons, there wont be a bottleneck anytime soon.


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## Fusion_power (Jan 14, 2005)

> I find that really hard to believe. Just reading here on beesource, there are _at least_ a hundred different folks doing a small handful of queens. Surely they aren't all using the same mother queen sources.


A course in quantitative genetics would help. You are incorrect. We are creating genetic drift in the population of bees in this country and that drift over time results in a narrowing of the genetic base. We don't have that strong of a genetic base to start with. The number of queens brought into the U.S. was limited. Don't take this wrong though, there is still a lot of variation available, it is just not being tapped into and used and can't be so long as queen breeders continue to use stock with limited genetic base.


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## TalonRedding (Jul 19, 2013)

grozzie2 said:


> I know of other folks just up the road from us, haven't brought in a queen for 10+ years, yet have 30 hives going strong.


That's why bottle necking isn't the only aspect to look at. Not everyone is having this trouble. I also have a neighbor who runs about 50 hives. He has NEVER bought bees. He only uses swarms and cut outs. He has also NEVER bought a queen, he raises his own. He has been keeping those bees for almost 30 years now. His bees can be testy now and then, but they are very hearty and great producers. Some people want to make a "blanket" diagnosis for the "apocalypse", when it's impossible to do. Locality, locality, locality.


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## marshmasterpat (Jun 26, 2013)

With AHB coming up from Mexico and spreading through all the states south of ??? but spreading that infusion of genes through some of the California, Texas, and Florida breeders whether widespread or not, that is minimizing the genetic bottleneck. With the importation of the Russian genome into the US, 10 to 20 years ago (I have not a clue when they were brought over) that would significantly reduce the genetic bottleneck but throwing a new gene set into the crockpot. 

Plus you have the bees that are in Mexico breeding with AHB and moving as well, there is significant genetic dilution. Look at the movement of the AHB through the America's as a model of how much genetic movement there is around the landscape. Yea, commercial breeder and commercial beekeeper might be causing a lot of genetic stagnation (might???) but I wouldn't bet on it. 

Then looking at each free mating female that mates with 5 to 20 males and each mating increases the potential of genetic diversity on the next supercede or swarm queen she produces. While the 700 or so breeder queens might narrow up the genetic diversity, the existence of feral black bees across the landscape in many parts of the US indicate that there are multiple genotypes out there and that indicates significant genetic diversity. 

There are species of animals that have much less than 700 individuals and yet within those species, genetic testing that has been done to detect genetic bottlenecks and threats, researchers are seeing enough gene drift that the species are not consided to be facing significant genetic issues. Just a scientific fact. 

Talon - I second that locality, locality, locality.


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## Phoebee (Jan 29, 2014)

longshotgene said:


> I have a question for the scientific minded out there? I know from a genetic standpoint, one can create a genetic bottleneck by crossbreeding the same genetics over and over. In effect, you can create what you think is genetically pure, but in reality, you have produced something with very weak genetics. Is it possible with the limited gene pool every country is dealing with, that we are in effect bringing the diseases that are appearing on ourselves? What research has been done on these diseases having existed prior to the recent outbreaks? The Africanized bees are a recent addition to the gene pool. What has been their history in relation to fighting these new diseases that are hitting? Are they affected?


Inbreeding can severely weaken a particular line. If you want some examples in humans, just look up the breeding practices of Pharaohs or European Kings. There was a usual course in Pharaohnic dynasties. After some military action in which one general was highly successful, and political conditions were ripe, he might become Pharaoh, establishing a new dynasty. To maintain a pure bloodline, the Pharaoh would have a child by one of his daughters, and that child would become the next Pharaoh. A few generations later the new Pharaoh was a drooling idiot and it was time to start a new dynasty with fresh blood. But there was plenty of genetic diversity left in the general population ... there was always a new general.

The problem is pretty much self-correcting. It can strengthen specific traits in carefully controlled breeding experiments of agricultural animals, but these rarely have any ability to survive in the wild, and a lot of the results wind up as culls.

What produces a genetic bottleneck is either a near extinction in which genetic diversity is lost, or management practices that effectively do the same thing. Inbreeding itself is not so much the problem as monoculture. If we all get our bees from just a few suppliers, that's a problem.

The matter of all domestic cats having a common female ancestor is new to me, but maybe. It is definitely true, at some distant point in the past, with humans. Likely this was the successful line coming from a genetic bottleneck, although not necessarily. It could simply mark a point in which a new and highly successful gene appeared. And in a sense, that IS a genetic bottleneck ... a single point of origin that by luck was not eaten by a lion.


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## Phoebee (Jan 29, 2014)

This is just slightly off topic, but it does in a way pertain to bees, and definitely to inbreeding.

There is an old quote, Shakespeare, I think:

"A rose, by any other name, would smell as sweet."

To those of us with some grey in our manes, this brings back some fond memories with a sad outcome. Us old fogeys remember when roses were about the most wonderful-smelling flowers you can imagine. I keep going up to them for a sniff. I don't think I've caught a wiff of their scent in three decades except from perfume bottles. I believe Chanel No 5. is rose scent.

Inbreeding and selective crossing to make new and bigger blooms has totally killed the scent in most varieties.

I'm sure some of the original stock still exists in the gardens of a few old grandmothers. Just as there are a handful of ancestral wild horses, and wild cattle, etc.

Yes, in some cases inbreeding and intensive management of stock, coupled with either killing off the wild population or destroying their habitat, can totally replace a wild variety.

I'm not sure that is happening with bees in America. What I see is a melting pot of Apis mellifera subspecies and races, able to reproduce in the most amazing mix (mutt bees with genes from Russia to Egypt and beyond), where previously there were no honey bees at all, and with a conscious effort to get away from monoculture bees. They're seriously challenged by the imported pests, but I think the long-term odds are good they will, with this much diversity to draw on, eventually produce regionally successful mixes. Yes, it is good to worry about these things, so you won't make the rose mistake.


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## Fusion_power (Jan 14, 2005)

Phoebe, find John F. Kennedy rose and purchase one for the smell.

The old roses are still around and they still smell just as sweet as they ever did. You just have to know where to look for them. Visit the international Rose Garden in Portland Oregon if you have a chance. I recommend visiting sometime in July or early August. You can smell the roses from 100 years ago and decide which you prefer.

Strike It Rich is a new rose that thoroughly impressed me. Eden climbing rose is another new one that was outstanding.


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## Phoebee (Jan 29, 2014)

Well God bless! I knew they must be out there. For sure you don't find them sold at most garden centers, or planted in gardens supplied from those garden centers.

So the next question, and I honestly don't know, is our usual question these days: "Do the bees like 'em?"


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## WLC (Feb 7, 2010)

We do have a collection of old garden roses (heritage roses). Yes, they do have wonderful fragrances. I have seen some bees on them, but not a lot.


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## Daniel Y (Sep 12, 2011)

It has been a while but I used to have a couple of climbing roses called Pink Perfume. you did not even have to go near them to smell them. I sit see them for sale. no promises that they have retained the scent.


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## JBJ (Jan 27, 2005)

I would bet the number of alleles in the US bee breeding population has increased substantially in the last decade or two. Newer to the US we have the Australian, Russian, the recent imports of several lines from Sue and the WSU crew; not to mention AHB and the initial diversity in the founding populations. 

How common is inbreeding depression in our honeybees? I am betting not very. Honeybee mating system encourages and creates diversity... polyandry, differential mating flight radius for drones vs queens, and the highest degree of crossing over observed in any organism studied. Without the use of II and extreme isolation creating an inbred line is next to impossible, or at least highly unlikely. 

Try it... it is actually difficult.


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## deknow (Jul 17, 2006)

http://www.beeuntoothers.com/index.php/beekeeping/audiovideo/30-archived-conference-videos

Randy Quinn Video
Randy speaks soberly of the effect that selecting for a few traits and requeening colonies en-mass with these hybrids from closely mated lines has had on the diversity of the gene pool (both from the selection on the breeding end, and in the introduction of homogenous hybrid stock into apiaries).* He promotes an old (and almost never talked about) practice of requeening by making a split to ward off swarming (making sure eggs, honey and brood are present within the split).* Simply wait two months, and recombine the two colonies.* In most cases, you will end up with a new queen (and in those that you don’t, you are likely better off with the old one).*


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## JBJ (Jan 27, 2005)

Error message if you click on that video...

Anybody have solid documentation of inbreeding depression in US bee populations? I would be surprised if it is happening to any significant degree naturally.


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## deknow (Jul 17, 2006)

Apologies

https://www.google.com/url?q=http:/...twIwAA&usg=AFQjCNGJb6YQTcQ2GSgxGl-aJGaaF3vZVw


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## Fusion_power (Jan 14, 2005)

JBJ, there is a difference between inbreeding depression, genetic drift, and genetic bottlenecking. I would agree that we are not having a problem with inbreeding depression and I would stipulate that there is not a serious genetic bottleneck. I think I can show significant amounts of genetic drift. Most of it is caused by mite pressure but quite a bit more is from commercial queen breeders selecting for specific traits in relatively shallow gene pools. Fully resolving this question would require a mass gene study with samples collected throughout the country and compared. This would be graduate thesis level material, not for the faint of heart or limited wallet.


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## JBJ (Jan 27, 2005)

Fusion_power said:


> JBJ, there is a difference between inbreeding depression, genetic drift, and genetic bottlenecking. I would agree that we are not having a problem with inbreeding depression and I would stipulate that there is not a serious genetic bottleneck. I think I can show significant amounts of genetic drift. Most of it is caused by mite pressure but quite a bit more is from commercial queen breeders selecting for specific traits in relatively shallow gene pools. Fully resolving this question would require a mass gene study with samples collected throughout the country and compared. This would be graduate thesis level material, not for the faint of heart or limited wallet.


I am aware of this and agree. 

A mass gene study like you describe was done a number of years ago pre-importation of Australians, the WSU program, and maybe even the Russians. I will see if I can find a reference and specifics. It was presented a our tri-state bee conference and looked at matrilineal DNA I believe.


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## JBJ (Jan 27, 2005)

http://www.bioone.org/doi/abs/10.1603/008.102.0411

This study compared mitochondrial DNA in 2005 populations to 1993. 

ABSTRACT

"Genetic diversity levels within and between the two commercial breeding areas in the United States were analyzed using the DraI restriction fragment length polymorphism of the COI-COII mitochondrial region and 10 polymorphic microsatellite loci. The western commercial breeding population (WCBP) and the southeastern commercial breeding population (SCBP) were sampled in 1993–1994 and again in 2004–2005. The goal of this study was to characterize the genetic composition of these populations and to measure potential changes in genetic diversity and composition across the sampling period. The mitochondrial DNA haplotypes C1 and C2, characteristic of the most popular bee strains (Italians and Carniolans, respectively) sold in the United States, were the dominant haplotypes at both sample dates. The frequency of Apis mellifera mellifera M haplotypes, M4, M7, and M7′, decreased during the 10-yr span. An A1 haplotype characteristic of Africanized bees was found in the SCBP from 2005. Microsatellite analysis showed there was a loss of alleles in both the WCBP and SCBP, but the losses were not significant due to simultaneous gains of new alleles into these populations between 1993 and 2005. Genetic differences that occurred between the 1993–1994 WCBP and SCBP were still detectable in these populations sampled a decade later, suggesting that these populations could be useful sources of diversity for each other in the future."


We have since aquired even more alleles in our breeding population.


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## Fusion_power (Jan 14, 2005)

JBJ, I read that article a year or two ago. Read between the lines and it strongly supports the conclusion that genetic drift is occurring, both within populations and between populations. Note that the original intent was to measure how much diversity was present but in the process, they happened to uncover an infusion of external genetics and signs of significant genetic drift. I'm not saying this is bad, just that it is occurring. The problem with this is that it occurred in a 10 year period. Significant changes as shown by this study only occur as a result of intense selection pressure.

The study as done is not adequate to prove or disprove narrowing of the gene pool nor does it adequately demonstrate genetic drift. A proper genetic base study should have millions of samples from across the country taken at two points separated by several years in time.


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## JBJ (Jan 27, 2005)

Agreed once again.

One could argue genetic drift is a natural phenomena and not inherently a bad thing.


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## WLC (Feb 7, 2010)

This is from the Darger thesis:

"We hypothesized that the samples would separate into distinct
populations delineated by lines of latitude. The samples tested in our study are not in
Hardy Weinberg equilibrium, as shown through the use of the Fisher’s test in
Genepop, which is indicative that they are not separate and distinct populations as
would be expected based on geographic collecting locations. Essentially, our study
indicates that bees on the east coast are not in distinct populations as would be
surmised based on collection latitude. Northern bees were not differentiated from
southern bees."

"Through the geometric wing analysis performed by Dr. David De Jong, several
patterns emerged. The unmanaged and managed samples clustered together,
separately from the representative type of each subspecies (A. m. liguctica, A. m.
mellifera, A.m. carnica and A. m. caucasica) (Figure 2), showing that the bees in the
US are a distinct hybrid."


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## WLC (Feb 7, 2010)

Richard Cryberg said:


> WLC said:
> 
> 
> > In my opinion, the current bottlenecking has occurred for some very basic reasons:First, there are 700-500 breeder queens, and they may, for the most part, be too hybridized. They're too similar to each other genetically.Pure nonsense. No rational person can possibly actually believe 500 - 700 as being right. Maybe 5000 - 7000 with the attendant 100,000 drones. 500 - 700 is what you get from an unsigned troll (or is that redundant?). The genetic bottle neck is pure fiction.Dick
> ...


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## Phoebee (Jan 29, 2014)

Heh ... So after following this thread I was upstairs reading the latest Science News. The back page article shows the drop in cost of gene sequencing over the last couple of decades. When I was in school, reading genes was a fond hope. Techniques were worked up to do this with gel electrophoresis and the like. They started out the Human Genome project this way, predicting the time it would take to complete. But you can't keep clever people just sitting around going G ... A ... T ... G. They figured out machines that could do it. Now they have these little things no larger than my desktop laser printers that just DO it. A sidebar mentions the "DNA Fire Hose, 36,000 streaming HD movies equivalent raw data flow of one Life Technologies Ion Proton P2 Sequencing machine" that looks like a large clock radio. Sheesh.

It works the other way, too. 20 years ago I remember seeing a $10k machine that could make DNA from a letter sequence. I wonder what they go for now.

We are approaching $1000 to get your own DNA sequenced. Total base pair sequencing, not just some allele sampling to see how much Neanderthal is in you. They think this may soon not even be recorded because it will be cheaper to run it again than store the data.

On a whim, I looked up DNA sequencing machines and an old one in good condition is listed on e-bay for $128 ... who would want it with the new ones available.

The time is coming where arguments are moot, excuses are no excuse, and you just stick a bee into your analyzer and find out what it _really_ is. Which will probably tell you far more than you really wanna know.


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## marshmasterpat (Jun 26, 2013)

JBJ said:


> I would bet the number of alleles in the US bee breeding population has increased substantially in the last decade or two. Newer to the US we have the Australian, Russian, the recent imports of several lines from Sue and the WSU crew; not to mention AHB and the initial diversity in the founding populations.
> 
> How common is inbreeding depression in our honeybees? I am betting not very. Honeybee mating system encourages and creates diversity... polyandry, differential mating flight radius for drones vs queens, and the highest degree of crossing over observed in any organism studied. Without the use of II and extreme isolation creating an inbred line is next to impossible, or at least highly unlikely.
> 
> Try it... it is actually difficult.


Would agree 101%.

Didn't know about the importation of the Austrialian bees, but with the recent influx of Russians and the movement of AHB genes into the main stream, I just do not see a potential of a bottleneck in the overall population. Maybe among the powerhouse queen breeders, they are supplying bees with similar genetics, but I think with the dilution of those genes by wild bees, every small breeder that is raising "survivor bee", "northern bees", "treatment free", and the "mutt" bees, there is plenty of different genetics coming into play. Each of these breeders are pushing a different genetic package into the KEPT bee population. 

It has been way to long since genetics and way too many bottles of beer and whisky consumed to remember all the specifics. However, I thought that even within a closed population, the infusion of 5% new genetic stock caused enough genetic variation to overcome the issues on inbreeding. And is that not what genetic bottlenecks cause. Perhaps not to the point expressed by the European or Egyptian royalty, but it would create a similar genotype to appear. Yet within the commercial queen breeders available, there are several distinct genotypes being expressed, which would indicate less chance of a bottleneck. 

I think there is several wildlife species with the good ole USA that prove this is a fact. In fact there are more than just several, but that is another point that is tied back into habitat. LOL, and back to my beer.


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## honeydrunkapiaries (Oct 16, 2013)

There is one study I can think of off the top of my head, which suggests that genetic diversity is important in the longevity of the queens. http://phys.org/news/2013-06-genetic-diversity-key-survival-honey.html


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## deknow (Jul 17, 2006)

Assuming the write up is accurate (I haven't looked at the paper), it talks about number of drones (more than 7 vs less than 7) that the queen mates with.
It may be that from the standpoint of 'genetic diversity', 5 completely unrelated drone matings may be more 'diverse' than seven matings that come from a couple of lines.
I think the number of matings is related, but not the same as 'diversity' or 'bottlenecking'. Traits become 'fixed' in the population both by giving advantage to those with, and by culling those without.
To one extent or another, this is 'bottlenecking'. My point about the cat having one single female ancestor is that bottlenecking doesn't always result in disaster.
Can you imagine the news headlines if we thought this was happening right now? Environmental disaster. A population so inbred it can't persist.

deknow


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## Michael Bush (Aug 2, 2002)

There have been issues with small gene pools in endangered animals and with some closed human populations such as the Hutterites or the Amish. It may be an exageration to assume that it always ends in disaster. My guess is that house cats have bred with some of the smaller wild cats over the years, though. I've seen some I was pretty sure had some bobcat in them based on size and looks.


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## Phoebee (Jan 29, 2014)

Michael Bush said:


> There have been issues with small gene pools in endangered animals and with some closed human populations such as the Hutterites or the Amish. It may be an exageration to assume that it always ends in disaster. My guess is that house cats have bred with some of the smaller wild cats over the years, though. I've seen some I was pretty sure had some bobcat in them based on size and looks.


Religious sects have their own unique issues. The Shakers didn't believe in having sex, which was self-correcting. Then, of course, there's Jonestown, or the occasional group of saucer-nuts.

There's some unique ancestry in Manx cats. I recall our Manx had kittens, and one of the four was hideously deformed and died shortly after birth. Evidently that number is typical ... they don't breed gracefully with ordinary domestic cats, which probably indicates that their species is close but not a match to the domestic housecat. I don't recall the specifics of this but I believe it has been investigated. There was something a couple of years back that I think indicated their actual lineage was not what had been guessed.


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