In the organic realm, infant mortality is an important observed phenomenon, with an elevated infant mortality rate being observed in a wide range of species. The study of elevated infant mortality from an evolutionary perspective is part of what is known as Life history theory.Several factors account for elevated infant mortality - for example:
- The small size of infants makes them less able to store resources - and thus more vulnerable to resource fluctuations.
- Some infants are widely dispersed but face patchy environments - where not all of them can thrive.
- Infants are often produced in huge numbers - and there aren't enough resources available for them all to survive to adulthood.
In the 1930s, Ronald Fisher proposed a general concept that covers many of these ideas - known as reproductive value. Reproductive value varies over the lifespan of an organism, reflecting their future reproductive potential. Old organisms have low reproductive value (their expected lifespan is lower and their fertility is reduced) and often infants do as well - due to the kinds of factors mentioned above. Fisher proposed that mortality rates could reasonably be expected to be optimised by natural selection to be proportional to the inverse of reproductive value.
Reproductive value is a concept which is closely related to fitness. Like fitness is is quite a general concept. However, as with fitness it is worth distinguishing between actual reproductive value (measured after the fact) and expected reproductive value - which is calculated on the basis of some other predictive theory about how inherited traits and the environment combine to affect the performance of the organism.
Though the concept of reproductive value is very general it is also often vague. For example, it follows that if infants are produced in huge numbers in each generation they will outstrip their resources, their reproductive value will be low - and there will be high levels of infant mortality. However here, high infant mortality follows directly from high birth rates - and invoking the concept of reproductive value didn't really help very much. It also doesn't help to answer the question of why so many offspring are produced in the first place. Isn't mass infant death very wasteful? In the case of widely dispersed seeds facing a patchy environment, some waste seems inevitable. However, in other cases, natural selection between the offspring may play an important role - weeding out those organisms with deleterious mutations or bad gene combinations by making sure that they "fail fast".
This brings us to cultural infant mortality. Culture provides a new domain for life history theorists with many interesting examples. What can be learned? What can life history theory contribute?
First there are some similarities. As with DNA genes, some memes face a patchy environment. Most flyers are trampled into the ground; the street preacher's ranting mostly gets no further than the sidewalk - and so on. Memes are also mass produced in far greater numbers than can ever survive. Radio and TV signals are broadcast in all directions. Some make it into space, where they could survive for a long time, while most others quickly hit dirt and turn into heat. Start-up companies and IT projects also exhibit high rates of infant mortality.
Also as with genes, many memes are end-of-line copies - with a limited lifespan and a low chance of personal reproduction. Most artifacts are like this. They are the equivalent of somatic cells of cultural evolution - their primary purpose is to assist the reproductive memes in the factory that made them - via cultural kin selection. Life history theory treats these end-of-line copies a bit different from germ-line copies.
Unlike DNA genes, the memes in artifacts often don't have very flexible control over their associated life history variables. If your main strategy for persisting is to be hard and strong that doesn't result in very much flexibility regarding senescence rates. DNA has mastered regeneration - and can more flexibly allocate resources to maintenance processes over the course of a lifespan. Artifact regeneration is a thing - as some automobile owners can attest. However, many artifacts are hard for end users to repair and they often get trashed at the end of their natural lifespan.
Another thing that most memes are not very good at yet is growth. Without growth, infants are not small, and so suffer less from predation and mechanical insults. Of course, some cultural forms do grow. Cities, roads networks and telecommunication networks all grow. However, most artifacts don't really grow - and without growth there is much less scope for infant mortality. Many memes aren't good at growing today. However we are still near to the origin of cultural evolution and it seems reasonable to expect that this limitation will disappear once we have easy access to robust molecular manufacturing technology.
High infant mortality is often regarded as a bad thing. However from the perspective of Darwinian processes, high infant mortality has some desirable aspects. If something is going to fail it is often best if it fails fast. Investments in components that are going to fail are often bad investments: it is better to spend the resources on something that is not going to fail. For many long-lived organisms there's a high-intensity selection process around the time of conception: gamete selection. More failures can occur during gestation and around birth. Rather than lamenting these failures, Darwinism suggests that we should regard them more as part of a natural process of weeding out the weak and unfit before they can do more serious damage to a family's resources.
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I question whether we are as close to the origin of memetic evolution as this post asserts.
ReplyDeleteArtifacts are hard for end users to repair--but this is shaped by labor specialization, proprietary information and other economic factors--protective, memetic traits which regulate repair and reproduction for artifacts within their environmental and memetic context.
As for not lamenting the biological failures (failed conception, failed gestation, failed birth, etc)...that lamentation arises from multiple memetic origins in cultural environments...including the joy (personal and communal) of a desired and successful gestation. While a distanced, objective view considering resource expenditures may counterbalance such cultural pressures, let's not forget that such reflection requires a level of privilege and security quite remote from the subsistence struggles which characterize the majority of human experience. Let us also consider that negative emotional outcomes of such an experience may be hard-wired into the human brain as an artifact of our species tenuous foothold on this planet over our emergence. These issues are highly complex. The simplistic sentiment of framing these experiences as "a natural process of weeding out the weak and unfit before they can do more serious damage" is what makes some perceive evolutionary theory and memetic theory as heartless. Observing adaptation demonstrates we cannot fully predict what traits or oddities might (given the right circumstances) prove to be a strength or allow an individual to exploit a previously unaccessible niche or resource--or what knowledge of a variation and that individual's experience might confer to the society which embraces (rather than dismisses) that variation.
FWIW, I regard the proposed depreciation of the rights of fetuses and infants as a women's rights issue. Rights over reproduction assigned to infants are rights that have been subtracted from women. There's a long history of taking these rights away from infants and assigning them to their mothers. There's also a long history of this progress being opposed by religions and fathers. The "right to life", they call it. Unwanted children are bad for women and bad for society. It isn't heartless. It is true that it involves caring about the infants less, but it does so through caring about the mothers more - which makes a lot of sense.
DeleteAnd if a woman wants to have a child with Downs Syndrome...are you going to insist that's an immoral and anti-social desire? If she and her family and community are so privileged they can make that conscious choice that they want to explore what such a long-term commitment might teach them...will you insist that's against the natural order? It's the same fanaticism of the religious right, only in reverse--it's a dogmatism that betrays academic curiosity.
ReplyDeleteFYI--I didn't say anything about the "rights" of a fetus or an infant. I'm about as pro-choice as one can get. But I do believe in dialoging with the 'opposition' and re-considering my own assumptions. I also don't believe in empowering a state or the powers over me to decide if my child is "fit" enough to be born, to be educated, to marry, etc.
Pro-choice to me means 'pro-choice'--I may think a woman is being short-sighted in carrying certain pregnancies to term...but I will defend her right to make that decision over her body--and I will support her socially and materially through that decision--no matter what factors & influences may be impacting that decision. We are all confined and influenced by our memetic melieu.
Her body, her pregnancy, her right, her choice.
People raising downs syndrome kids probably weakens humanity and slightly increases our chances of eternal oblivion - compared to them deciding to do otherwise. The issue is whether something can be done about it. I figure something can fairly easily be done - and that there will be no downs syndrome kids born after a little while.
DeleteTo date, evolution hasn't been too good at recording its mistakes and avoiding them in the future. It keeps making the same mistakes over and over again. However, avoiding past mistakes is one thing that brains are good at. As well as building on past successes, an efficient search often involves avoiding making the same mistakes repeatedly. We will get there, I figure. Mistakes are part of evolutionary progress (as this post argues), but repeated mistakes need not be - at least not when bookkeeping is cheap enough.
Tim, you are so focused on "mistakes" and "improvement" that you miss out on the larger picture. Ever considered you might learn something about common humanity from socializing with some "evolutionary mistakes", and that this might help you flesh out your academic discipline?
ReplyDeleteLast I checked, humanity isn't suffering the threat of extinction at any comparable rate to other species. And if we do, in the future, it will be due to our destruction of the biosphere and other lifeforms--it will have little to do with permitting evolutionary "mistakes" and other such scapegoats. As far as our chances of eternal oblivion--it's gonna happen. Every organism goes extinct eventually--even if they outlast all other organisms. We're too high up on the food chain to avoid it...but even blue-green algae will meet its end when the sun expands. Even if we become star-faring, we won't last forever. The universe is ever-changing and our brevity in it makes our time valuable.
"Avoiding eternal oblivion" isn't intended to imply indefinite survival (that would be "eternally avoiding oblivion"). It just means not going extinct. It's supposed to read like "avoiding dying". Each year, I have avoided dying. That isn't intended to suggest that I will live forever, just that I've managed to survive so far.
DeleteIn fact, practically all of your comments seem to be criticizing things that I didn't say. For example, I didn't claim the chance of our extinction was high relative to other species. Nor did I speculate about the contributions of various negative influences to that chance.
If you think Down syndrome has some redeeming features, presumably there are some birth defects you would be prepared to assign negative value to. Anencephaly perhaps. Anyway, plenty of parents do, in fact, assign strong negative value to rearing offspring with Down syndrome - and they abort fetuses which are diagnosed with it.
I think many modern civilized societies still assign too many rights to fetuses. I regard this as a hangover from their religious and patriarchal histories. History can judge my position on this. If, in the future, women get more rights at the expense of the rights of fetal rights and paternal rights, I will regard my position as having been vindicated. Yes, that will probably mean more abortions and fewer very sick newborns. If you think that would be undesirable, then we probably disagree over values.
I'm not saying that's undesirable, rather saying illness and unpleasant circumstances have potential for scientific understanding and learning. Certain conditions might shed light on memetics.
ReplyDeleteMy apologies for the awkward wording--I see it seems I was saying you commented about the potential for human extinction compared to other species. What I was trying to demonstrate is the quantity of the human population (compared to species facing extinction, especially other top-level consumers) indicates that concern over how genetic anomalies might impact our species survival or extinction is rather null.
Even if we experienced a population crash (common when a species experiences the exponential growth we've enjoyed over the last 500 years) we are spread out over the globe in such a way that the continuation of the species is likely for the foreseeable future. (Not to mention survival instincts tend to trump cultural convictions when an individual experiences severe stress).
This point was crossed with another idea (which on reflection wasn't fully articulated) that we should be more concerned about the extinction of other species, and the potential this has to undermine humanity's survival.
My concern is that you speak as an community educator, a specialist in a discipline (which confers social status if not authority) and instead of saying "abortion has been a common human practice" or "couples may choose abortion, and need not feel negatively about it" you push the issue (at least in the word choice, if not your intent) by saying this is what should be done. That places an expectation, a moral burden, considering the social context (in that many people frame such a decision in a "moral" framework)--even if that is not your intent. Richard Dawkins does the same, and it blows my mind that such rigorous intellects cannot perceive this context, but instead assume that any indignation exhibited by others is due to residual religious or patriarchal ideas. (Or, perceiving this context, they believe turning the tables and roughly dismissing objections is an effective communication strategy).
My objection is to the preservation of the moral absolutism which distracts from memetic investigation.
(Which may result from English being a strongly-typed moralistic language--certainly not your fault.)
My objection is that you haven't moved past a gut response of "that's horrible, we should avoid it" to "well, when it happens, what do we learn from it?". I take slight offense that you may be looking at my gender and demographics and thus making a judgement about my thought processes instead of dialoging to get some accurate data (though this may be an unfounded assumption on my part).
The sentiments of others, present and future, cannot vindicate us.
We must stand on our own feet and own our thoughts, even if we are in the minority or alone.
The majority, the consensus, can be mistaken.
I do not assume genetic testing / effective prenatal diagnosis is available to all in the present, or in the future.
I do not assume to know what is right for every individual in their personal context.
I do not believe one has a right to dismiss the conviction of someone else if it's deemed to be a 'hangover from their religious and patriarchal histories'. Such convictions should be studied, articulated, traced--investigated on an intellectual level, dialogued with--not just for one's own learning and development, but for the learning and development of those who hold the convictions.
Science isn't about the salvation of the few, the chosen, the high IQs, it's about the collective improvement of our common lot. I am indebted to the educators who dialogued with me and empowered critical thinking without undermining my determination when faced with swimming against the current. Such an approach strengthened me.
Darwinian theorists fairly frequently have views that impinge on moral issues. Peter Singer is a classic example of a moral thinker who draws on evolutionary theory. While Peter Singer's utilitarian view seems fairly far out to me, I notice that his views on abortion and infanticide are similar to my own - and have a similar rationale.
ReplyDeleteI think it is OK post such material on my blog. I think that modern society is overly sensitive about squishing fetuses - resulting in children who are unwanted by their mothers. Maybe such material is a bit off-topic but, let's face it, a post on cultural infant mortality is going to be the most on-topic place I have for airing such material for the next decade.
I do know some things about how defects can act as illuminating natural experiments. Leigh Hoyle's "Genes, Memes, Culture, and Mental Illness" is certainly illuminating. On the other hand, scientific illumination doesn't seem like a great reason for encouraging the production of infants with birth defects.
Lastly, I think you might perhaps be underestimating Dawkins. Stirring up a shit-storm of controversy might perhaps be seen as a marketing effort. Notoriously, there's no such thing as bad publicity.