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Sunday, August 30, 2015

Sagittal crests, Part II

Dr. Timothy Jorden --


-- killed his girlfriend Jacqueline Wisniewski and then committed suicide in Buffalo in 2012. Jorden had been a very accomplished man, too: before he became a trauma surgeon he'd been in the Special Forces.

At the time, one of the things that struck me was his sagittal crest. As explained in the previous post, sagittal crests evolved to allow easier anchor for the jaw muscles, resulting in a more powerful bite. Sure enough, both Jorden and Shannon Miles, the fellow in the previous post, have wide jaws -- indicative of strong jaw muscles.

Both men were physically powerful as well, though I'm not sure those two things are related. Jorden stood 6' 2" and weighed 250 pounds. And here is the surveillance photo of Miles taken around the time he shot that sheriff's deputy two days ago:


Miles looks as if he could have been a good football player had he been so inclined.

Here is a picture of Markale Deandra Hart, a murderer who was featured on this blog this past December:


He, too, has wide jaws -- and an evidently powerful build -- to go along with his sagittal crest.

Michael Clarke Duncan, the actor, was evidently a nice guy. But he has the powerful jaw muscles to accompany his crest, and he, too, had an extremely powerful build:


Four guys aren't much of a sample. And if you Google-image "human sagittal crests," all you get are photos of ancient skulls. But, I'm going to keep an eye peeled for further evidence of correlation.

6 comments:

Quartermain said...

Just a brief comment on the first example. It takes more than just physical fitness, passing AirBourne Ranger training but the candidate has to have a high enough score in their Army entrance exam.

John Craig said...

Allan --
Yes, and getting through Special Forces selection camp takes even more fitness. It's a grueling three week test of strength, coordination, and most of all endurance. You have to be able to think clearly when exhausted, march forever, and also have no phobias, since the SF tests you on virtually every single major fear. The group of guys who try out for that are already a set-selected bunch of tough, fit guys, and out of that group, roughly 30% make it through the camp.

Runner Katy said...

I'm so glad you have pointed this out, as I've been thinking about this for years now, but thought it was just a strange coincidence in killers, people shown involved in crimes and such on the news, and other "off" people that I have noticed over the last few years. I assumed it was a silly notion since I've never read anything to suggest that this obvious Sagittal crest had any correlation to crimes or sociopaths. Wouldn't it be nice if we had a physical trait that gave us a kind of "heads up" on people that could commit such heinous crimes?

John Craig said...

Runner Katy --
I'm glad I'm not the only one who's noticed this. As I said, four people isn't a significant sample size, but I was struck in each case by the correlation between the crest and the jaw muscles and the overall build. I'm not sure how much of a heads up it'd be; I'm sure there are plenty of decent people -- like Michael Clarke Duncan -- with that trait. But the idea that it is an atavistic trait, correlated with strength and the potential for violence, is one I find interesting.

prpa said...

I've already commented on the previous post with this topic, I'd just like to add that it seems the keel(not crest) is more prevalent in black populations because of their genetics, but the violence is widespread due to the sociological factors of American society so it's not a direct correlation, there are just a lot of violent blacks and a lot of them with sagittal keels, so it would be strange if there were no criminal blacks with keels...then it would mean something, you can't have a scientific evaluation on just the examples that already fit your preconceived theories, there are a lot of blacks who are murderers without having any apparent physical atavistic traits, so no, unfortunately, you can't tell if someone is a murdering maniac just by looking at them..most of the timeX), and it also depends on the eye of the beholder, no?

John Craig said...

prpa --
As I said in this post, four guys isn't much of a sample, but in each of these cases the crests (or keels, if you prefer) and the muscularity and the violence were all striking. There's absolutely no question that muscularity correlates with male hormones, and that male hormones correlate with a propensity towards violence. The purpose of the keel is to anchor the chewing muscles (as well as to provide protection against blows to the head). If the chewing muscles are larger, you'd think this would correlate with overall greater muscularity, which, as I've said, correlates with a tendency toward violence. I didn't draw any conclusions from this post, since four guys isn't a big sample; but I was struck by these four, one of whom, as I pointed out, was evidently a nice guy.

Nobody questions that sociological factors feed into people's behavior. But to totally ignore the crime statistics, which remain consistent year after year, and to turn a blind eye to all sorts of racial differences -- like IQ, and testosterone levels -- which feed into behavior, and which have little to do with socioeconomic background, it to be willfully blind. As far as my "preconceived theories," they weren't "preconceived," but have followed a lifelong observation of these differences.