The May 4, 2012, issue of the journal Science includes three briefs from the annual meeting of the American Association of Physical Anthropologists, one of which has a few choice words about telomere lengths. In case you hadn’t heard, studying telomere length is all the rage now as it apparently has some correlation to longevity. I don’t know. The whole thing seems fuzzy to me. Remember when neutrinos were going faster than the speed of light? That didn’t last long now did it?
As these creased and dog-eared magazines get passed back and forth at our family dinner table I had my brilliant wife (a real scientist) on hand for questioning.
“So is this telomere stuff for real?” I asked her.
“Mmm-hmm,” she said with a shrug. “It looks that way.” So there you have it, from the seat of authority.
Let’s refer to the Science journalist here:
Telomeres are repetitive sequences of DNA that prevent the ends of chromosomes from unraveling, much like the plastic tops on the ends of shoelaces. As cells divide and replicate, telomeres get shorter and eventually can no longer prevent the fraying of DNA and the decay of aging. Recent studies have found a link between living to 100 and having a hyperactive version of telomerase, an enyzme that keeps telomeres long.
If you’ve got long telomeres on your chromosomes then genetically speaking this is beneficial and improves your chances at living a long life. But what factors determines telomere length?
The results of some very interesting new research (cf. Science vol.336, pg.539) suggest that telomeres in sperm cells are proportional in length to the age of the man. Thus the older the father is at conception, the longer the telomeres of his offspring. The researchers found that this effect extended to grandfathers as well, passing on their telomeres to their son’s children but not their daughter’s children.
This doesn’t necessarily mean that older dads have great genetic advantages. In fact as we age our gametes are more likely to contain mutations, so there are definitely some benefits to having younger parents. But I couldn’t help but be prompted to reflect how reproductive advantages of older men might have had an impact on the organization of society.
Certainly when it comes to mothers, experience pays serious dividends in terms of reproductive fitness. As Sarah Blaffer Hrdy writes in Mother Nature, among primates first time mothers are generally less successful but since mothering is learned behavior this can improve with time. Thus:
Given a choice between two sexually swollen females, male chimps invariably choose the older one. It is interesting to speculate why men in some societies differ from other primates in this respect, placing so much emphasis on youth. One reason, I suspect is that these men are in a position to monopolize access to their mate and to literally possess her long-term. (186)
So human sexuality, as we can observe it today, is always already in the context of patriarchal relations. This may even extend to the cultural valuation placed the beauty of youth, which is desirable not because young people make better parents but because young women yield long term benefits for older men.
On the theme of “interesting to speculate” we might question whether older men hold some benefits in terms of the reproductive fitness of younger women. There is after all this ubiquitous pattern, seen around the world, of older men shacking up with younger women. This is readily observed in the age difference between spouses, with the male partner typically older than the female partner. What is the basis for this? How far back in human history does this pattern extend?
One outcome of this pattern is that from the beginning of the affinal relationship the male is in a privileged position as the elder. Of course, there are other factors that may be more relevant than the age difference of the spouses when it comes to understanding household micropolitics. For example, there are social and cultural reasons why a woman might choose an older man to be her mate. An older man might have command of more economic resources, or he might have more clout and authority in the community — things that can make a big difference when it comes to raising offspring to reproductive maturity.
Now perhaps we can count another “pro” in the advantages of older male spouses: longer telomeres. Because men and women have different reproductive strategies, a man who can sire children well into his maturity can have additional opportunities to enhance his fitness unavailable to his shorter lived peers. And this trait of longevity may be passed down to his offspring, and his son’s offspring.
Really? Do we really have to leap from older men having one specific genetic advantage to offer his offspring to “So human sexuality, as we can observe it today, is always already in the context of patriarchal relations.”? Give me a break.
I’d recommend a book by Bernard Chapais for answers to this. It’s called Primeval Kinship, Harvard University Press, 2008. Really excellent book – probably the best book on kinship that I have ever read – and it has realistic answers to a lot of questions people have about kinship, while leaving a lot of room for studies of cultural variation. I think it’s superior to Hrdy’s work, and that’s saying something.
I don’t think longevity can be much of a factor here. Until about 1800, in almost every country on earth life expectancy hovered around 40 years for both men and women. Only in the wake of the industrial revolution in Britain and the Netherlands did the number start to creep up. (Incidentally, hard as it is to believe now, in 1900 as a result of this increase in life expectancy and population the UK had one of the top 10 largest populations on earth.) So longevity has never been all that important, I don’t think.
As for the link between telomeres and the apparently universal trend for men to be older than women at marriage, I’m not so sure. It would need thinking about. I don’t think it’s all that viable, honestly, given that longevity has never been important as a variable (due to the general shortness of human life until the past two centuries) and given that longer-lived males would only end up competing with males of other generations for mates, a situation which seems untenable. But there are other sides to it, I expect.
Thanks for the tip, Al. I’ll be sure to look for Chapais — sounds very interesting!
By “mothering” she seems to mean ‘child-rearing.’ Yes, older females (and males!) tend to get better at it with practice. That doesn’t change the fact that all other things being equal, a fifteen–year–old is going to be a better choice as a baby factory than is a thirty–year–old. The modal evolutionary psychologist seems to suffer from such an overfixation on pair bonding that s/he does not recognize that there are plenty of societies where teens do a lot of the baby-having and greyhairs do a lot of the baby-raising.
An English translation (by Nora Scott) of Godelier’s Métamorphoses de la parenté has now been published (as The metamorphoses of kinship) and should be of interest to everyone. This article should be of particular interest to you, Matt.
All things being equal a younger body is better than an old one for a first pregnancy, but subsequent pregnancies may lead to easier births for mature women. The question here is if this also holds true for males as it does for females, or whether something else is going on.
In the continued spirit of trying to gently suggest that there are a lot of things that need to be unpacked here, I don’t see how that could be the question. Because men do not get pregnant or give birth. The deleterious effects of advancing age upon both human sperm telomeres and ova does suggest some interesting analogies between males and females vis-à-vis conception. What I am trying to say is that the analysis of human biological and social reproduction needs to take care to distinguish conception, gestation, partus, and child rearing. Individual researchers also need to look closely at some of the assumptions they may be making about the relations amongst the four.
I mentioned the pair bond concept because it seems to me that while pair bonding may well be of central importance to post-Fordist human reproduction, the pride of place afforded it by researchers pretending to study a time scale equal to the whole of human evolution is questionable at best if the entirety of logical and ethnographically demonstrated conception/gestation/partus/child rearing combinations are taken into account. Plenty of other concepts could use the same treatment, fitness and unit of selection being amongst them.
I was wondering if one’s telemore length is correlated to the age of your father at your conception and the age of your grandfather at your father’s conception, then what kind of social and cultural practices might allow such a trait to spread through a population?
Well, someone had better inform the Yale administration of these findings so they can reverse their ban on all faculty-student sexual relations! Given the potential ‘evolutionary benefits’ of older man/younger woman pairings, let us (as anthropologists especially!) not stand in the way of naturalizing patriarchy or legitimating the exploitation of gender inequalities/power asymmetries.
Sarcasm aside, given the ways in which gender inequalities often play out on this site, especially in relation to the comment streams following posts, I too have to raise the proverbial eyebrow in relation to the anemic discussion of patriarchy and (abuse of) power involved in this discussion and the frequency–and desirability–of younger woman/older man pairings.
Long time lurker, first time commenter, and I really enjoy reading your blog; I love anthropology; people are a fascinating species to study!
Hm. There also is research showing that kids born to older fathers have a higher tendency to autism and/or schizophrenia, on the other hand. Could we say it’s a wash? Perhaps in some eras and societies, having an older father was an advantage (for instance, in stratified societies where men control most of the wealth and get richer as they get older) and other times and places where there was more of an advantage to having parents close in age (say unstratified foraging societies where women contribute quite a lot to subsistence and it matters more if a father is kind than rich).
It strikes me that whenever some new discovery can be interpreted as “a-ha! this is evidence for patriarchy” or “pair bonding” or, in short, what fulfills the status quo or some idealized 1950’s era gender roles, people are on it like white on rice. Evidence for polyamory or female dominance tends to get challenged or dismissed. This i s just how I see it.
No, I’m not a trained anthropologist or a trained scientific anything – just an interested and nerdy member of the lay public – but it seems quite a leap to me from “telomeres” to “older man/younger woman pairings are inherent to the species.” It confirms the beliefs of a lot of people, including, dare I say it, older men doing the studies and who might have some wishful thinking going on (wishful thinking is NOT confined to feminists, believe it or not).