Why 'Sexual Mind Control' Is Rare in Nature | Hacker News Reader

Why 'Sexual Mind Control' Is Rare in Nature

news.sciencemag.org

22 pointsyiedyie20 comments

It's a simulation. In other words, the only conclusions that the scientists can really draw out are those that were hard-coded into the organism behaviour to begin with. For instance, they speculate that perhaps it might be a disadvantage to the parasite to have to generate powerful hormones - yeah, they would have had to have written that particular parameter into their simulation. Alter the parameter slightly, and you change the outcome.

To wildly speculate they as well might have been interested from a technical point of view because they could have grown on animals parasites that grow testosterone this could have had commercial purpose. etc.

Most of the simulation results for things like this are dubious at best. Seems like money better spent to me to focus research energy on more useful endeavors. However, some simulations are extremely useful and really do represent reality well.

The key is if you can match the simulation parameters to the results, so you can say "if the disadvantage of having to produce hormones to control the host becomes less than X, then we see sex mind control appearing - we generally don't see this in nature, so it must be more disadvantageous than X to produce hormones". That's a real result.

I'd say that it is in the host's own interest to maximize sexual activity given all other constraints (long term survival and reproduction).

This is why a parasite won't be able to improve (or optimize) it further since it is fully aligned with the host's incentives.

TLDR: You can't improve what's already optimal

Survival of the offspring is also a factor. Better one that makes it to adulthood than ten who do not.

From a mystic point of view Kundalini cannot be hijacked :D

I agree with that point with respect to the host's fitness. But the conflict here stems from the fact that those other constraints (such as the host's long term survival or reproduction) has little or no value in itself to the parasite, so there's a chance to have a mismatch of fitness objectives between the host and the parasite.

Is there a conflict? It seems probable the only purpose of surviving is to increase the odds of a successful reproduction.

If I understand correctly, you suggest that a parasite would sacrifice "long term survival" or "offspring adulthood probability" to achieve increased reproductive success!?

Hmm, the host could for example go on a "raping spree" but it unsure how this would lead to _significantly_ increased reproduction (I suppose this is an energetically costly enterprise) and why the raping spree wouldn't be already an "integrated" behavior if it were so successful.

In this case 'a parasite would sacrifice host long term survival or host offspring adulthood probability to achieve increase it's own reproductive success'.

The article concerns parasite manipulation of host behaviour, and to the extent that such manipulation can take control the host will act in the parasite's genetic interest rather than it's own.

Why have parasites promoting mating success been observed so rarely?

Paywalled article: https://www.sciencedirect.com/science/article/pii/S002251931...

Abstract:

Host manipulation by sexually transmitted parasites which increases host mating rate and thus parasite transmission rate has long been viewed as a plausible parasite adaptation. However, empirical evidence for it is rare. Here, using an adaptive dynamics approach to evolution, we explore conditions under which such disease-induced mating enhancement is (or is not) likely to occur. We find that increased mating success is less likely to evolve if the host reproduction rate, or the baseline disease transmission rate, is reduced, and the parasite affects just one sex, compared to when it affects both. We also find that it is less likely to evolve if the virulence-transmission trade-off curve is stronger, since we assume that enhanced disease transmission can only be achieved at the cost of increased virulence and as this trade-off is concave. In addition, we demonstrate that if disease-induced mating enhancement is equally acting in both sexes the mating system has no effect on evolutionary outcomes. On the contrary, if disease-induced mating enhancement is acting in just one sex, the potential for its evolution increases with the degree of polygyny in the host population. To study the examined phenomenon in greater detail we encourage further empirical research on this apparently less explored impact of sexually transmitted parasites on host fitness.

This is just what the mind controlling parasites want you to think.

«The researchers speculate that sexual mind control either costs too much energy for the parasite, causes too much harm to the host, or both» Judging by the harm to the host(see Sex and the City) the City has that energy, that if we see the City as a parasite.

Dawkins in "the Extended Phenotype" argues that manipulation such as 'Sexual Mind Control' is very common in nature. One of examples that he gives is a female cricket that is 'programmed' to react to a male song. He writes:

'The object's internal chain of command — sense organs, nervous system, muscles — may be infiltrated and subverted. A male cricket does not physically roll a female along the ground and into his burrow. He sits and sings, and the female comes to him under her own power. From his point of view this communication is energetically more efficient than trying to take her by force.'

Dawkins is just describing the mating habits of a very simple organism. It is not the same as a parasite/virus/whatever causing an increased libido.

I would start with wondering if all STDs have the purpose to be transmitted sexually. Like aids doesn't look to me like it's purpose is sexual transmission. Other exchanges of fluids might also result in infection.

The researchers speculate that sexual mind control either costs too much energy for the parasite, causes too much harm to the host, or both.

Speculate? SPECULATE? How can they not know.

It's a simulation for god's sake! How can they not spit out an average for energy consumed per infected host? How can they not have that data?

Sounds suspiciously like pseudo-science.

So you accept that a simulation is a valid experiment, but feel that refusing to tell science press that natural phenomena fit the exact parameters of the simulation is pseudo science?

You completely misunderstood me. What I'm saying is how on earth can it be valid if they are speculating on the very basic questions.

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