A second argument is that a lot of our behavior is governed by memes these days, not genes. It’s certain that the memes that survive are the ones which best reproduce themselves; it’s also pretty plausible that exposure to memes can tip us from one fitness-maximizing behavioral strategy to another. But memes forcing us to adopt a highly suboptimal strategy? I’m sceptical.
There are memes to die for—as Dennett loves to point out in his many lectures on the topic.
However, memes are more likely to sterilise than kill. Memes are widely blamed for the demographic transition. They are why there are so few kids in Japan.
It seems like there would be strong selection pressure against it; to pass the memes on but not let them affect our behavior significantly. Memes existed in our ancestral environments too.
Sure, but the memes coevolve with the genes—and they evolve faster. Today they are much more dense and numerous and potent than they were for our ancestors. We do have an evolved memetic immune system—but it is having a hard time keeping up. DNA-evolution can’t just magic defenses against computer games and interactive pornography into existence.
The memetic model is of apes with infected brains—infections that dramatically alter their behaviour. Memes are what make us different from the most primitive cave-men.
There’s strong selection pressure on us to develop immunity to harmful memes. There’s no selection pressure on the meme to be harmful to us. So we win, don’t we?
(It’s different with parasites; there’s no selection pressure for them to harm us as such, but they are competing with us for resources, which will ultimately harm us. The only resource that memes require is talking time).
Of course memes can flip us from one adaptive (or nearly adaptive) behavior to another. I think it’s pretty clear they do at least that much. So I’m left trying to explain why committing suicide and having fewer children might be adaptive behavior.
Suicide may be regarded as failed parasuicide. Self harm and attempted suicide is seen as a cry for help, but what if the person is in a society where help actually gets provided? They may end up more likely to reproduce. (But it’s a very costly signal so that person would have to be pretty desperate).
The demographic transition is easier to explain. Societies that are peaceful, highly wealthy and with high population density are not stable; they are prone to collapse due to invasion or using up a resource. And if you’re faced with possible societal collapse, you’re probably better off producing fewer children and investing more in each one.
There’s strong selection pressure on us to develop immunity to harmful memes. There’s no selection pressure on the meme to be harmful to us. So we win, don’t we?
(It’s different with parasites; there’s no selection pressure for them to harm us as such, but they are competing with us for resources, which will ultimately harm us. The only resource that memes require is talking time).
Memes require resources too. Harmful memes are just like other pathogens—so they are selected for increased virulence, increased ability to compromise host immunity, increased ability to divert host resources into the production and distribution of memes—and so on.
So I’m left trying to explain why committing suicide and having fewer children might be adaptive behavior.
Not a very promising approach. Suicide is very unlikely to be adaptive—and it is pretty well established that the demographic transition is also maladaptive:
The continuing decline of fertility to below replacement levels in many parts of Europe (both richer and poorer parts) is unlikely ever to find an adaptive explanation.
I’m updating: I concede I was likely talking nonsense regarding suicide memes. Memes are sort of like viruses in that they really want to spread themselves but don’t necessarily require that much in way of resources from the host. Yet deadly viruses exist.
So I think I’d expect deadly memes to spread in “outbreaks” and “epidemics”, like viruses do, but not to hang around a population for generations gradually sapping everybody’s reproductive ability.
I’ll try and dig up Boyd and Richerson. Do you know if they address my particular hypothesis (collapse precursor?) I couldn’t see any mention of it with a quick googling—are such hypotheses so easy to generate that there are dozens of them out there and people only address the leading ones?
So I think I’d expect deadly memes to spread in “outbreaks” and “epidemics”, like viruses do, but not to hang around a population for generations gradually sapping everybody’s reproductive ability.
The memes that gradually sap the reproductive ability.of many are not “deadlly”. They are more like cold viruses, and persistent viral infections.
Boyd and Richerson don’t look at your collapse hypothesis. They argue that the number of kids is so small in many cases that it can’t possibly be adaptive.
There are memes to die for—as Dennett loves to point out in his many lectures on the topic.
However, memes are more likely to sterilise than kill. Memes are widely blamed for the demographic transition. They are why there are so few kids in Japan.
Sure, but the memes coevolve with the genes—and they evolve faster. Today they are much more dense and numerous and potent than they were for our ancestors. We do have an evolved memetic immune system—but it is having a hard time keeping up. DNA-evolution can’t just magic defenses against computer games and interactive pornography into existence.
The memetic model is of apes with infected brains—infections that dramatically alter their behaviour. Memes are what make us different from the most primitive cave-men.
There’s strong selection pressure on us to develop immunity to harmful memes. There’s no selection pressure on the meme to be harmful to us. So we win, don’t we?
(It’s different with parasites; there’s no selection pressure for them to harm us as such, but they are competing with us for resources, which will ultimately harm us. The only resource that memes require is talking time).
Of course memes can flip us from one adaptive (or nearly adaptive) behavior to another. I think it’s pretty clear they do at least that much. So I’m left trying to explain why committing suicide and having fewer children might be adaptive behavior.
Suicide may be regarded as failed parasuicide. Self harm and attempted suicide is seen as a cry for help, but what if the person is in a society where help actually gets provided? They may end up more likely to reproduce. (But it’s a very costly signal so that person would have to be pretty desperate).
The demographic transition is easier to explain. Societies that are peaceful, highly wealthy and with high population density are not stable; they are prone to collapse due to invasion or using up a resource. And if you’re faced with possible societal collapse, you’re probably better off producing fewer children and investing more in each one.
Memes require resources too. Harmful memes are just like other pathogens—so they are selected for increased virulence, increased ability to compromise host immunity, increased ability to divert host resources into the production and distribution of memes—and so on.
Not a very promising approach. Suicide is very unlikely to be adaptive—and it is pretty well established that the demographic transition is also maladaptive:
Boyd and Richerson 2005, p.173.
I’m updating: I concede I was likely talking nonsense regarding suicide memes. Memes are sort of like viruses in that they really want to spread themselves but don’t necessarily require that much in way of resources from the host. Yet deadly viruses exist.
So I think I’d expect deadly memes to spread in “outbreaks” and “epidemics”, like viruses do, but not to hang around a population for generations gradually sapping everybody’s reproductive ability.
I’ll try and dig up Boyd and Richerson. Do you know if they address my particular hypothesis (collapse precursor?) I couldn’t see any mention of it with a quick googling—are such hypotheses so easy to generate that there are dozens of them out there and people only address the leading ones?
The memes that gradually sap the reproductive ability.of many are not “deadlly”. They are more like cold viruses, and persistent viral infections.
Boyd and Richerson don’t look at your collapse hypothesis. They argue that the number of kids is so small in many cases that it can’t possibly be adaptive.