infanticide in the u.s.

i came across these stats from the bureau of justice statistics while looking for something else. i thought i’d post them, even though they make me sad. =(

from Homicide Trends in the U.S. (2007) [pdf]:

infanticide rates - u.s. - graph

well that table pretty much speaks for itself.

parents are the perpetrators in most homicides of children under the age of five…

infanticide rates - u.s. - relationship with offender

…but the key thing to remember here is that the bureau includes STEPPARENTS in these figures. then you’re (naturally) gonna get the cinderella effect — mostly men getting rid of the offspring of other men.

and it is mostly men. from page 34 of the report (remember “fathers” includes stepfathers):

“Of all children under age 5 murdered from 1976-2005 —
– 31% were killed by fathers
– 29% were killed by mothers
– 23% were killed by male acquaintances
– 7% were killed by other relatives
– 3% were killed by strangers

“Of those children killed by someone other than their parent, 81% were killed by males.”

and they’re mostly young, reproductive-age men (and women) — again, naturally. on page 23 we learn that 81.3% of the perpetrators of infanticide were between the ages of 18 and 34.

also, a gruesome fact that i posted about before: stepparents, typically, kill their stepkids (when they do kill their stepkids) in a more brutal fashion than biological parents do. =/

and … i didn’t realize … men kill more male children than female. very interesting:

infanticide rates - u.s. - by sex

males getting rid of rival males’ male offspring. fascinating.

also interesting, the younger the child, the greater the risk for infanticide:

infanticide rates - u.s. - by age

i wonder if this has to do with very young children — babies — not really having a “personality” yet? yes, i know that they do when you really know them, but you know what i mean — a five year old kid has a more … observable, noticeable … personality than a five month old. maybe it’s kinda “easier” to kill something without much personality than a little person that talks back to you? dunno.

if i were to give women any advice, i’d say be very, very careful in picking your second husband or next boyfriend/baby daddy if you’ve got a young kid(s). and i’d be extra very, very careful if picking an african american man as a second husband/boyfriend/baby daddy. if i were to give men any advice, i’d say keep a watch on your ex’s choice of any subsequent partners if you’ve had a kid(s) with her.

previously: the cinderella effect, again and more on the cinderella effect and evo psych in need of a little hbd? and killing kids & step-kids, part ii

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more on the cinderella effect

greying wanderer suggested the other day that a murderous person would prolly stab a stranger with a knife up “to the hilt,” but if he went to stab his brother, he might, at the last second, have a change of heart and only stab the blade in an inch or two.

there might be something to that notion. what he said reminded of something i read a while ago now, around the time i had a couple of posts about the cinderella effect, i.e. that step-parents generally don’t treat their step-kids as well as biological parents do. this makes sense, of course, if you keep inclusive fitness in mind, ’cause step-parents are (usually) not related to their step-kids.

what i read was a really interesting, but depressing (esp. for a chick, i think), article entitled “Some Differential Attributes of Lethal Assaults on Small Children by Stepfathers versus Genetic Fathers.” what the researchers found was that, not only do step-parents kill their step-kids at much greater rates on average than biological parents, but that when they do, it’s usually a more violent, brutal affair. when biological parents do kill their own kids, they tend to do it in a rather clean, almost humane way. and they more often kill themselves as well afterwards.

“Killings of children less than five years of age by stepfathers versus (putative) genetic fathers are compared on the basis of Canadian and British national archives of homicides. In addition to previously reported differences in gross rates, the two categories of killings differed in their attributes. Beatings constituted a relatively large proportion of steppaternal homicides, whereas genetic fathers were relatively likely to shoot or asphyxiate their victims. A substantial proportion of killings by genetic fathers, but almost none of those by stepfathers, were accompanied by suicide and/or uxoricide. These contrasts lend support to the hypothesis that the differential risks incurred by children in different household types reflect the differential parental solicitude that is predictable from an evolutionary model of parental motivation.”

here are some charts.

methods of killing of children under five, canadian study — that first category is “beat”:

methods of killing of children under five, uk study — the categories from left to right are “hit, kick, blunt object,” “shoot,” “suffocate, strangle, exhaust fumes,” and “all other”:

relatedness matters. even — or maybe especially — in the most gruesome scenarios.

so, if you’re a parent, and you’re thinking of re-marrying (or re-shacking-up, altho that’s prolly a bad idea anyway), CHOOSE CAREFULLY.

btw — you would think that it would also make a difference if, say, a child was mixed-race or mixed-something. in such a case, the biological parent would clearly be less genetically related to their child than in a family that was 100% swedish or chinese, for example. not to mention all the cousin-marriage scenarios i’ve been talking about (ad nauseum). you would think, all else being equal (like economic circumstances), that there ought to be less child killing by parents in a place like saudi arabia.

and, that’s all i’m going to write about this subject (for now anyway), ’cause it’s just too d*rn sad.

previously: evo psych in need of a little hbd? and killing kids & step-kids, part ii and the cinderella effect, again… and even plants do it and more plants playing favorites

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the cinderella effect, again…

An evolutionary perspective on perceived parental care and closeness in adolescents. How do biological and social kinship play out within families in the U.S.?


“Consistent with inclusive fitness theory, evolutionary biologists predict that individuals care more for their biological than their social children and hence that biological children assess the relationships to their parents better than stepchildren. To test this assumption, we use data from the U.S. National Longitudinal Study of Adolescent Health (Add Health). Unlike many other studies that have been conducted so far, this survey allows us to analyze the consequences of the dynamic between social and biological parent-child relationships within the same families. We use comparisons of sibling pairs and fixed-effects regression to achieve the within-family comparison. Both the descriptive and multivariate regression results confirm that – even after controlling for other relevant influences – biological parenthood matters with regard to children’s relationship assessments (perceived parental care and closeness of the parent-child relationship) and in both the relationships to resident fathers and mothers. In the discussion, we comment on the possible integration of the evolutionary and sociological perspectives and close with some recommendations for future data collection that could allow researchers to analyze the relative influence of biological and social influences on parent-child relationships on a more fine-grained level….


“Starting point of this paper was the assumption that from an evolutionary perspective, parental care should differ between biological and social children in a way that disadvantages the latter, and that this difference should be mostly visible in families in which biological and social parent-child relations coexist…. The conclusion of the analysis is that biological parenthood matters: In all respects stepchildren do provide lower assessments of the relationships to their parents than biological children do.”

previously: evo psych in need of a little hbd? and killing kids & step-kids, part ii

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