> On Sep 10, 2015, at 9:49 AM, Charles Linder <[log in to unmask]> wrote:
> 
> A Virulant mite that continually collapses hives it inhabits is dooming itself. 

I should remind you that the varroa mite is very successful. The strategy of redistributing mites, while leaving colonies to die, has worked out OK for it. Of course, the survival of any organism is never guaranteed. Plenty went extinct because of a strategy that lead to failure. But this is not that. The competition between parasite and host is called a Red Queen Race. JW Chesnut explains this nicely:

The endlessly-repeated common meme in these posts is "Varroa will naturally become benign if left alone". I nick-name this "the peaceable kingdom" faith (the famous painting from 1820 of Hicks). It is based on a conviction that nature is in "perfect balance" and an Eden-like paradise can be achieved in the American wilderness. This belief has spawned an entire sub-culture of advocates.

Host-parasite interaction and co-evolution is a rich and deep academic field. A paper by Troy Day and James Burn, A CONSIDERATION OF PATTERNS OF VIRULENCE ARISING FROM HOST-PARASITE CO-EVOLUTION (2002) is responsive:

"We find that counterintuitive patterns of virulence are often expected to arise as
a result of the interaction between co-evolved host and parasite strategies. In particular,
despite the fact that the parasite imposes only a mortality cost on the host, co-evolution
by the host results in a pattern whereby infected hosts always have the same probability
of death from infection, but they vary in the extent to which their fecundity is reduced."

In bees, this pattern is already observed: Varroa kills (via hyper-infection) honeybees regardless, evolution has pushed honey-bee survivors into high-swarm-frequency life strategy.

Honeybee/Varroa/Virus patterns are evolving systems. The dominant hypothesis in similar systems is called the "Red Queen" hypothesis. The model organism used is pond Daphnia. In short, the Red Queen idea is a rare, resistant genotype will arise.... and will reproduce with greater initial fitness. (this is step one in the "peaceable kingdom" theory of bees).

As the rare, resistant genotype of the Red Queen line becomes dominant --- the parasite will shift genotype to match -- and the level of parasite induced death will return to the initial level. In summary, unbalanced resistance is only temporary and is dependent on rarity of the trait. A review of the Red Queen idea is http://www.evolution.unibas.ch/ebert..._Microbiol.pdf

Varroa (and its attendant virus) has horizontal transmission. This means that the primary mode of infection is from one hive to a genetically unrelated nearby hive.

In this thread, two ideas about Varroa are being mixed. Treating is supposed to be breeding "super-Varroa" with more virulence. This is based on the observation that the rapidly breeding varroa have overcome resistance to the specific miticides they have been exposed to. These are not "super-virulent" bugs, they are bugs that have absorbed the genetic and metabolic cost to resist a single compound. Resistance to Amitraz does not persist -- it is costly to the bug and is discarded unless constantly selected for. 

I maintain the "natural" advocates are the villains breeding the "super-Varroa". Small cell is advocated because it supposedly shortens the gestation time of the bee larvae by a day. Doesn't that argue that Varroa co-evolution will quickly produce a mite with a shorter generation time. Small-cell (in this thought experiment) is creating a monster race of Varroa with a 20% greater reproductive potential.

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