I am wondering if it's true that there are, or were, inbred families or communities that live(d) in the Ozark Mountains. Was it just the movie Deliverance that led people to believe that? --Josh from Montreal
I hope not, because the Ozarks and the setting of James Dickey's 1970 novel Deliverance, source of the 1972 movie, are two different places. Much of the action in Deliverance takes place along the fictional Cahulawassee River, generally thought to be based in large part on the Chattooga River, which forms a length of the hilly border between Georgia and South Carolina. The Ozark Mountains are located mainly in southern Missouri and northern Arkansas. Though united by the wide belief that the south + hill country = inbred degenerates, the Ozarks and the Chattooga are separated by roughly 500 miles, several states, and the Mississippi River.
What you're thinking of is the Appalachian Mountains, which extend nearly 2,000 miles from Alabama to Newfoundland and encompass the Chattooga watershed. Northerners, evidently including Canadians, figure the southern end of the range is crammed with mental defectives, an assumption worth examining. If you don't mind, therefore, we'll restructure your question along slightly more scientific lines: Is southern Appalachia characterized by an unusually high incidence of (a) inbreeding and (b) mental retardation and genetic defects, and if so, has (a) led to (b)? For reasons to become apparent, we'll start not at the beginning or end of this question, but in the middle.
1. Does Appalachia have more mental retardation, etc? In a 1974 paper tactfully entitled "The Geography of Stupidity in the U.S.A.," researcher Nathaniel Weyl notes that the three states having the highest white failure rate on the Armed Forces Qualification Test in 1968 were Kentucky (14.8 percent), Tennessee (14.2 percent), and West Virginia (13.4 percent). Weyl attributes the "abnormally large proportion of white mental defectives in the Appalachian region" to, among other things, "the notoriously high rates of inbreeding among the Appalachian population." Lest you think Weyl has it in for Scotch-Irish hillbillies, he blames Maine's high failure rate (8.8 percent, 11th worst) on "the fact that a large proportion of her population descend from French Canadian immigrants"--and surely, Josh, you know what trash they are. Weyl's article, incidentally, appeared in Mankind Quarterly, which publishes a lot of research by the biology-is-destiny crowd.
2. Does inbreeding lead to genetic abnormalities? Time to waffle. Last year I wrote a column saying cousin marriage wasn't guaranteed to produce genetic defects. It's not, strictly speaking. However, defects may be more common than I let on. The problem is "inbreeding depression," the emergence of undesirable traits when closely related parents each contribute a normally dormant gene. According to one paper (Jaber et al, Community Genetics, 1998), congenital malformations are 2.5 times more common among offspring of inbred couples than of unrelated parents. A famous example is the "blue Fugates," members of an inbred Kentucky hill clan who suffered from a rare genetic blood disorder that made their skin look blue.
3. Is inbreeding unusually common in Appalachia? Here's where things get murky. Although the public and many social scientists have long assumed that isolated hill folk often marry their cousins, and some certainly do (ask the Fugates), research on the subject is pretty thin. The most comprehensive look I've found is a 1980 paper ("Night Comes to the Chromosomes [etc]," Central Issues in Anthropology) by Robert Tincher, who at the time was a grad student at the University of Kentucky. No matter; young Tincher was a bright and energetic lad. Having dug through 140 years' worth of marriage records in a remote four-county region of eastern Kentucky, he argues that (a) yeah, cousin marriage happens in the hill country, but (b) rates vary widely from place to place and even among families in a given district, and (c) it isn't conspicuously more prevalent than in a lot of other places. Point (c) isn't all that persuasive; Tincher's numbers show that as late as 1950 inbreeding was well above what could be accounted for by chance--married couples on average were approximately third cousins. However, the rate had dropped sharply since the peak after the Civil War, when the average couple were somewhere between second cousins and second cousins once removed. What's more, the rate fell quickly after 1950--no doubt due to postwar prosperity, urbanization, and so on--and by 1970 was no higher than you'd likely find in the general population.
4. So? So whatever may have been true 50 years ago isn't necessarily true now. In the recent indicators of national intelligence I can find--eighth-grade math scores and what all--southern Appalachian states aren't conspicuously clustered at the bottom. On the contrary, notwithstanding the blue-state-smart-red-state-dumb malarkey you sometimes hear, I'd say stupidity in our society is pretty uniformly spread around.
Art accompanying story in printed newspaper (not available in this archive): illustration/Slug Signorino.