Coevolution of Honey Bees and Varroa Mites: A New Paper

[WLC]

Treatment-free bees are arguably resistant via evolution by natural selection.

What evolved?

Some pretty smart scientists in Sweden couldn't identify that conclusively in the Gotland hives.

Silly me, I split a DWV infected hive and decide that maybe somebody should try and get some hard evidence for treatment-free resistance via evolution (transgenesis).

How do treatment-free beekeepers demonstrate disease resistance?

It's a fair question.

[sqkcrk]

Because they used to die a lot, now they don't.

Do you have another suggestion?

I might suggest you answer Bill's question.

[jbeshearse]

Mike,

First, I thank you for your measured and well presented response, yet we disagree on many of the points.

Second, my apologies for the length of this post. Normally this would mean that it will not be read by many and mostly ignored. I hope that is not the case.

Third, I mention treatments a lot in this text. I do not relate to how to manage non-treatment, etc. This is not an endorsement for treatments. I think that those that do not treat, and manage their apiaries rather than just rob honey from the manmade structure they have convinced the bees to live in are doing all of us a favor. If this does not belong on the treatment free forum it can be moved. But as this is where the discussion started it is the logical place to continue.

jbeshearse: Until such a time that the parasite species declines to a level which allows the host species to rebound.

Mike Bispham: What you mean is 'until such time that the host-parasite pair reach an accomodation that allows both to rebound.' From there on those hosts better at reducing the effect of the parasite will prosper at the expense of those less well able to control them.

jbeshearse (reply): No, the host species cares nothing about accommodating the parasite. In host/parasitic relationships, the parasite is dependent on the host, not the other way around. What you refer to is more of a symbiotic relationship, which is not, to the best of our knowledge, present in the Honeybee/Varroa relationship. A host, if successful will find a way to minimize the parasite or minimize the negative results of the parasite’s presence. However it does bear noting that the “co-evolution” aspect would lend itself to more of a symbiotic relationship than a host/parasite relationship, as far as building stable populations of both are concerned. But for symbiotic relationships to endure, there has to be an evolutionary benefit to the relationship (both species benefit).

jbeshearse: Treatment free or treated will have little to no effect on the overall honeybee resurgence.

Mike Bispham: This is inconsistent with the stand taken in the paper; to the effect: it is treatments that prevent the co-evolution of host and parasite (and virus).

jbeshearse (reply)" First, I see nowhere in the paper’s stand that says treatments prevent the co-evolution of host and parasite(virus). Your quote from the abstract in your original post on this thread highlights the only place it even takes a stab at that and then it only says “hinders”, not prevent. The body of the paper does not try to prove this is the case. Also from your quote of the abstact, It goes on to say that apicultural practices remove the mite and consequently the selective pressures. That is a bad assumption on the paper’s authors. Mites exist, even in the treated hives and they are building resistance to the poisons used on them. I do agree completely with the paper however in believing that the poisons (treatments) for mites are hindering the evolution of mite resistance in the overall population. But it is not stopping it.

jbeshearse: After the majority of feral (treatment free) colonies perished (probably 90%+), those that remained had better coping mechanisms and are slowly rebuilding populations.

Mike Bispham: Where they are free of the influence of treated drones the rebuilding is rapid

jbeshearse (reply): Where is this treatment free nirvana? I don’t doubt the sincerity or your statement. However, if it was that simple, the beekeepers that treat would have already taken notice and be using these rapidly rebuilding populations to supplement their operations. I imagine we will see those that treat (myself included) treating less and less until not at all as the “treatment free” bees supplant those requiring treatment. Also see below, in this context we are poisoning varroa, not inoculating bees. If anything the treated drones you are referring to are lightly poisoned and may be over time developing a resistance to those poisons themselves (as a species, not individuals)

jbeshearse: The managed populations are experiencing the same thing.

Mike Bispham: They are? What is your evidence for this claim?

jbeshearse (reply): In my area, there seems to be a resurgence of feral colonies as compared to populations from 3 years ago. This is personal observation based on number of swarm and cut out calls, not scientific survey. This is not an isolated area of untreated bees. However, that aside, why wouldn’t they rebound with a degree of similarity? This discussion concerns the treatment or non-treatment for varroa. It is an important distinction that the treatments are to control varroa, not the bees. “Treatment free” encompasses much more than varroa tolerance/survivability. The issue with treating for varroa is the concern that the varroa become resistant and stronger than the treatments can manage, and thus harm the bees more. It is not that the bees necessarily get weaker but that the varroa get treatment resistant. Once again, people who treat and manage bees will select the best survivors. It stands to reason that the bees that would require no treatment would also be the best survivors, treatment or not. So in effect they will represent an ever larger portion of the overall “treated” populations. Because the bees that would normally succumb without treatment are allowed to reproduce, they will slow the infiltration of treatment free bees into the populations not prevent it. Evolution demands this, survival of the fittest. If treatment free bees are the fittest, then they will still be the fittest, even when all are treated.

Further, what is being selected for? I think part of where the treatment/treatment free conversation is failing is that a lot of people are confused as to what is being treated and what the results and implications of those treatments are. For this discussion the treatments are for varroa. This assumes that the varroa are being treated (poisoned), not the bees. In effect what treatments are doing is developing a stronger varroa species, not a weaker bee species. But stronger in this case means resistance to pesticides, not resistance to inherent traits of the bees.

jbeshearse: Treatments do not kill that 10% of the managed population that would have survived anyway.

Mike Bispham: No, but they do allow the other 90% to reproduce freely. That prevents adptation. Entirely. If you subjested a 'survivor' population to the same regime, within a few years they'd be equally vulnerable.

jbeshearse: The managed population may take longer to to reach the same level of hardiness as the ferals (treatment free), as those that are not adapted are treated and thus survive.

Mike Bispham: It isn't a case of taking longer. It will never happen because (as the paper reminds us) selective pressure is removed by treating.

jbeshearse (reply): This does not prevent adaptation, only slows it, as the other 10% will continue to reproduce also and as they are less likely to succumb, will eventually represent a larger and larger portion of the overall population. The only way it would prevent it is if the other 10% were not allowed to reproduce. There is always selective pressure. In a population that is treated, the bees that would not have needed treatment should survive better than those that did not need treatment. It represents one less pathogen, etc that would cause that particular bee to die without reproducing. Furthermore, as previously stated above the premise is wrong, treatment has not removed the mites. It is a case of taking longer, not of happening at all.

jbeshearse: In reality, treatments are an effective way to insure overall populations do not severely decline before the species rebounds on it's own.

Mike Bispham: There is absolutely no evidence that this is the case, and it flies in the face of fundamental evolutionary biology. It directly contradicts the clear statements, made by the authors.

Mike Bispham: Bees have a natural defence mechanism - shared by all living things: die-back to resistant strains: rebuild from resistant strains. This process carries no cost in terms of diversity.

Mike Bispham: Treatments frustrate that process entirely, and on an ongoing basis. Treating corrodes diversity by preventing the re-emergence of feral bees around apiaries.

jbeshearse (reply): What clear statements are you referring to? Please elaborate. Also tell me how this “flies in the face of fundamental biology.

jbeshearse (reply): We are not treating the bees for varroa, we are poisoning varroa and to a degree bees. This in no way removes the effects of fundamental evolutionary biology. Frustrate it yes, prevent it, no. As humans we interfere in the process, but we cannot overcome it. A die off is the last line of defense. Fundamental evolution demands that defenses that do not result in death will be favored over those that do result in death.

jbeshearse: I don't think it is an either or scenario, I think both practices are working together for the good of the species.

Mike Bispham: To think is easy. To make a convincing case you'll need to show where evolutionary biology is going wrong - and write a clear account. I don't think that will be so easy.

jbeshearse (reply): It is never easy to make a convincing case to entrenched positions. I never said that evolutionary biology is going wrong. I don’t even know where that came from. What I did say was that treatments are only a stopgap measure until natural selection takes over. Only a way to keep colony numbers suffieciently high to meet our needs until the balance is restored. If you read the paper, it says that the reason the European bee populations have suffered is a due to lack of time and selective pressure. Seems you only read selective pressure and ignored the entire “time” part.

[Solomon Parker]

Mark, just because you don't like the answer doesn't mean there wasn't an answer. Bill hasn't answered many of my questions and you don't see me complaining.

[sqkcrk]

I didn't recognize that your answer was to Bill's question and not to mine.

[Adam Foster Collins]

DOI: 10.1016/j...
Here's the abstract:

http://www.ncbi.nlm.nih.gov/pubmed/17275871

"... report that in bees (Apis mellifera), approximately 30% of all tested populations carry a segment of a dicistrovirus in their genome and have thus become virus-resistant."

I hope this helps to clarify what I've been going on, and on, about.

So let me attempt to restate and simplify this.

Studies are showing that 3 out of 10 tested honeybees are showing a portion of their genetic make-up has been acquired from their viruses. They are "genetically modified" by their viruses to become virus-resistant. Is that roughly correct?

Do we have any idea how long it might take for modification like this to take place? Is just the presence of the virus enough to cause it with any regularity?

Within the 30% showing a segment of a dicistrovirus in their genome, how many different viruses are represented?

Adam

[WLC]

Who is Bill?

[jbeshearse]

Why is doing nothing so dad gum difficult for so many people?


Where does this come from? This is pure speculation not based on any sort of evidence of which there is plenty. I've kept bees treatment-free for nine and a half years. I have only experienced a single swarm. This year I made 17 gallons of honey from five hives, four of which had been robbed of brood to make mating nucs.

It seems to me that this idea comes from the idea that it takes brood breaks and swarming to combat mites. It does not. Brood breaks are not necessary. Splitting is not necessary. Doing ANYTHING about mites is NOT NECESSARY. I notice no major differences between mine and any other population of bees except they don't swarm very much which I credit to keeping very large hives year 'round.


No, it is a very simple simple solution. For some reason, it's very hard for people to do.

Soloman, I guess your bees are not successful. The first thing necessary for propogation of the species is reproduction. If your bees only managed one swarm in nine and a half years, they are not very successfull in propogating the species. I suspect you simply do not see the swams.

[Solomon Parker]

I doubt it.

[Solomon Parker]

WLC, you are Bill. If you read my posts, you'd know that already. Something makes me suspect you aren't reading them. I guess there's no reason in continuing this conversation, with you at least.

Let the people decide. Does it make more sense to breed from diseased bees or from healthy bees?

[WLC]

Adam:

Here is a quote from a poster board presentation by Wayne Hunter et al.:

"Traditional PCR along with gel electrophoresis for each of these bee viruses showed that DWV and KBV have integrated into a segment of the A. mellifera genome."

http://flaentsoc.org/09festufts_hunter_integrate.pdf

Let me explain that the whole field of research involving retrotransposition into the Honeybee genome went 'dark' around this time.

I have found active retrotransposon activity in the R2 region of the 28s rDNA of A. mellifera however.

It's going to take some time for this field to open up again though.

[Adam Foster Collins]

Bill, Who is Andrew?

[WLC]

Adam:

We know that KBV and DWV were found integrated into the Honeybee genome here in the U.S., just as IAPV was found in Isreal.

They're not giving anymore details since.

WLC.

[Adam Foster Collins]

...
"Traditional PCR along with gel electrophoresis for each of these bee viruses showed that DWV and KBV have integrated into a segment of the A. mellifera genome."...Let me explain that the whole field of research involving retrotransposition into the Honeybee genome went 'dark' around this time...

So they realized the honeybee is naturally transgenic, so it seems likley that it wouldn't be too hard to make artificial genetic modifications which would make bees that are immune to certain viruses. Which is where Beeologics became very interested. You could make "namebrand" bees.

You go on to say "I have found active retrotransposon activity in the R2 region of the 28s rDNA of A. mellifera however." I have no idea what this means.

It's like you're sharing and not sharing at the same time. I'm glad to have what you offer, but one can easily get the sense - and perhaps it is your intention to communicate - that you have much more information than you're actually sharing.

It's a bit frustrating, but as i say, I'm thankful for what what you do contribute.

Adam

[WLC]

Adam:

It simply means that there's an active jumping gene in our Honeybees.

It's also very well characterized in other insects.

I think that it's always better to look for jumping genes in a place (the R2 site) that has a great deal of research behind it.

I also think that Beeologics blundered badly when it tried to market their technology to beekeepers.

It's a mistake that shouldn't be repeated.

But, it's a viable 'natural' option for treatment-free beekeepers.

Those genes jump during splitting, etc. .

[sqkcrk]

Those genes jump during splitting, etc. .

Gene splitting? Or colony splitting?

[WLC]

During reproduction. Those genes naturally jump in germline cells.

Thus, you split into an infected colony.

It's a modern genetics interpretation of how resistance can occur 'instantly' in Honeybees.

You heard it from me first.

WLC.

[Adam Foster Collins]

It simply means that there's an active jumping gene in our Honeybees...
...it's a viable 'natural' option for treatment-free beekeepers. Those genes jump during splitting, etc. .

So when, they talk about 30% showing a segment of a dicistrovirus in their genome, is that 30% of the bees within a colony, or 30% of colonies? Is this something that is going to show itself in a queen, and be necessary in a queen in order to appear in the workers? Or can it come from a drone? I guess I'm stuck on the question of how I can work to increase those percentages.

For the beekeeper, does it come down to splitting colonies under pressure, and observing how well subsequent colonies handle that pressure?

Adam

[Adam Foster Collins]

WLC says: "It's a modern genetics interpretation of how resistance can occur 'instantly' in Honeybees. You heard it from me first."

Adam says: Holy crap. And would that 30% translate roughly to the general population?

You say "during reproduction" with bees, that can be a variety of places. If I split an infected colony, and introduce a queen, does this kill the process? Do I have to let the split produce its own queen to get the potential benefit? I'm having trouble locating where the 'jump occurs' and how I work to assist it as a beekeeper.

You say "split into an infected colony" - what does "split into" mean? I can split, but then there is a portion with a queen and one without. The one without has to raise a new one using eggs from the old one, and then gets the genetic input from a random drone. OR I can introduce a mated queen from another source. Where does the jumping gene come into play? Is it simply the pressure that causes it to jump?

And consider this article "Published honey bee genome shows paucity of “jumping genes” "

A couple of quotes:

"Compared to other sequenced insect genomes, the sequence also clearly reveals that the honey bee genome has evolved more slowly and lacks major transposon or “jumping gene” families... "The honey bee genome is unusual in the sense that it appears to have very few transposons or retrotransposons in the assembled sequence, almost all of which are members of one family known as the mariner family.”... Transposons and retrotransposons in the honey bee constitute only about 1% of the assembled genome... it is unclear what the significance of this low incidence of mobile genetic elements in the honey bee genome may mean. It may reflect some evolutionary pressure to prevent detrimental damage to the organism’s genetic make-up over many generations."

This seems to suggest that the honeybee has far fewer "jumping genes" than a lot of other organisms.

[mike bispham]

Hi JB (Does that work?)

I obviously can't respond to a post of that length on a point by point basis, so I've just selected parts that might allow me to address some of the most important issues.

[Previously]

jbeshearse: In reality, treatments are an effective way to insure overall populations do not severely decline before the species rebounds on it's own.

Mike Bispham: There is absolutely no evidence that this is the case, and it flies in the face of fundamental evolutionary biology. It directly contradicts the clear statements, made by the authors. Bees have a natural defence mechanism - shared by all living things: die-back to resistant strains: rebuild from resistant strains. This process carries no cost in terms of diversity. Treatments frustrate that process entirely, and on an ongoing basis. Treating corrodes diversity by preventing the re-emergence of feral bees around apiaries.

jbeshearse (reply): What clear statements are you referring to? Please elaborate. Also tell me how this “flies in the face of fundamental biology.

I will elaborate. I'm going over familiar aground again, but I'm doing so to try to make a couple of points as clearly as I can. The first is about the nature and forcefulness of the principle of natural selection. The second is about the way that principle unifies many different explanations.

Here is the clear statement from the abstract:

"Coevolution by natural selection in this system has been hindered for European honey bee hosts since apicultural practices remove the mite and consequently the selective pressures required for such a process."

To those familiar with evolutionary biology or breeding sciences that statement needs no elaboration. Its a straightforward consequence of the general principle of natural selection for the fittests strains.

This is very very simple, but a clear understanding is essential!

Nature tends to breed more from the stongest individuals than from the weak. Since qualities are inherited, this passes more of the better qualities to the next generation than the less-good qualities.

There are many different mechanisms that press toward this outcome, perhaps the most obvious being that the weakest (most unfit) die before they are able to mate. The strongest reproduce the most, the weakest reproduce not at all, the middling ones reproduce in middling numbers.

Another powerful mechanism; the strongest males tend to win mating competitons. Again this contributes to each new generation tending to be made from genes supplied by the strongest parents. In these and other ways, generation after generation, weakness and vulnerabilities are winnowed out, on an ongoing basis.

Can you see how neat that is? If not, read it again, and think about it some more. When you feel some kind of shock at the sheer elegance of what goes on, a billion times a day, always, and how that is able to maintain life itself, please, hold on to that and don't let go! Come back to it whenever you feel wobbly! That is the underlying, fundamental principle of the organic sciences! Nothing less. You cannot argue with it, or twist it. It is simply a (rough) description of a fundamental reality.

In animal husbandry this process is copied. Now, instead of natural selection, artificial selection is used. The husbandryman chooses those parents that s/he thinks will make the best offspring, and uses those, and only those, as breeding pairs. ('Pairs' is misleading since often one male will sire many females - but they're all 'pairs')

The art of raising good breeding pairs is fundamental to the success or failure of the husbandry. Allowing weakly, slow-growing, or disease-prone stock to enter the breeding pool carries the probablity that those weakness will be reproduced in the offspring. And so any animal showing any deficiency is quickly removed as a contender for future breeding stock. Only the very best are allowed through.

Do you see how nature has been copied? How animal husbandry and natural selection are using the very same means to maintain health and vitality, and quickly take out weakness?

This is the golden rule of husbandry. Both nature and husbandry work with the fact that traits are heritable, that mother and father pass down parts of their make-up to their children. It isn't precise nor predictable in individual cases - but as things average out, it works.

Now lets marry to the above the following:

"Breeding is by no means a human invention. Nature, which in millions of years
has bought forth this immense diversity of wonderfully adapted creatures, is the
greatest breeder. It is from her that the present day breeder learnt how it must
be done, excessive production and then ruthless selection, permitting only the
most suitable to survive and eliminating the inferior." Friedrich Ruttner,
Breeding Techniques and Selection for Breeding of the Honeybee, pg 45

Now: Can you see how what Ruttner, one of the all-time great bee breeders, says is in complete agreement with my outline? Can you point to any strains or contradictions between what I've said and what he's saying?

I've sketched the evolutionary biology that underpins the statement made by the authors, and outlined the most basic animal-raising principle, and shown how Ruttner works from the same understanding. And there is complete concordance between them all. Complete agreement between scientists, animal husbandry principles, beekeeper. That concordance is that all are united by an understanding of this most basic principle of organic life - Natural Selection for the Fittest Strains.

There is complete concordance too between this web of interrelated understanding and the medieval dictum 'Put Best to Best.'

Can you see this? Can you see: this is the music of animal science, the tune that life dances to?

Stay with this. This is Golden.

Now: This process is - essential - to the maintainance of health. There is, we've heard, a sort of constant 'arms race' between every host and their many predators. The predators are constantly seeking to gain more food (for that's what its all about - everything needs food to live at all), the hosts must equally constantly seek to prevent that. The two populations therefore are locked in a sort of race, each seeking the upper hand. Constantly. And each uses the same tool, adaptation, evolution by natural selection.

And so... if you stop evolution in the host, you allow the predator to gain an advantage. In each generation.

Selection, by nature or by husbandryman, is then essential to prevent the predators gaining advantage.

Selection, by nature or husbandryman, is what allows - or creates - the necessary adaptation

So (last part): by logic: what happens when we prevent - or seriously inhibit - adaptation in the host by frustrating selection?

Something - anything - is essential. We remove it. What happens?

What does treatment do? It removes the natural selection that would otherwise occur. What happens when we stop the selection processes?

I can't do more than this. You have to be able to understand the dance, to hear the music, apply the understanding with simple logic. Then it all makes perfect sense, and you breath a sigh of relief, and sit in wonder at the magnificent elegance of nature's wonderful basic health-maintenance mechanism.

And the questions you ask me answer themselves, easily and naturally.

I've said far too much: the thing is beautifully simple and elegant. And what you have to do, as a husbandryman, is obey the dictum. Put Best to Best. Only.

Is that so hard?

If you keep looking until that is all properly clear and firm, you will be able to see that your next statement simply is not in accordance with the web of understanding that flows from the simple fact of inherited traits. I'll show you why:

jbeshearse (reply): We are not treating the bees for varroa, we are poisoning varroa and to a degree bees. This in no way removes the effects of fundamental evolutionary biology. Frustrate it yes, prevent it, no. As humans we interfere in the process, but we cannot overcome it. A die off is the last line of defense. Fundamental evolution demands that defenses that do not result in death will be favored over those that do result in death.

First, 'a die off' is not the last line of defence - the death of the weakest (without reproducing) is an important part of the _first_ line of defence!

Second: back to the paper: "Coevolution by natural selection in this system has been hindered for European honey bee hosts since apicultural practices remove the mite and consequently the selective pressures required for such a process."

Don't misread that 'hindered' - it doesn't signal a time issue as you think. Note the second part; the selective pressure is removed. Without selective pressure there will be no adaptation. Ever. Without sdelective 'pressure' on a population there is nothing to drive any change, nothing to adapt to.

jbeshearse (reply): It is never easy to make a convincing case to entrenched positions. I never said that evolutionary biology is going wrong. I don’t even know where that came from. What I did say was that treatments are only a stopgap measure until natural selection takes over.

The 'entrenched position' is the inarguable fundamental principle at the root of evolutionary biology. And what that tells us is: your 'stopgap measure' prevents natural selection from occurring. Natural selection, where it is given free rein works just fine. Where treatments are made it cannot work - and there is no adaptation. And that is the crux of the problem. That's why treatments are described as 'addictive'. The more you treat the more you need to treat. (Actually its worse that that: treating only a bit creates a downward spiral as resistance is progressively lost). Where treatments are removed, and husbandry is done properly, things work fine.

Can you see now how all the evidence fits together, and is united with the great web of understanding that is founded upon the recognition of inherited traits, and natural selection of the fittest?

Again: find that music. Dead animals don't reproduce; the strongest reproduce most, health is passed on down.... this _process_ is essential to life. Understanding it essential to successful husbandry.

You cannot treat and expect any adaptation to occur. Indeed, if you start treating adapted bees they will, over the course of a few generations, adapt to the new environment, and lose their resistance.

Best wishes,

Mike