May 21, 2010

Student Fan Mail

That was the title of the email I got from my current contact at W.W. Norton, where I've been a contract writer creating online content for physical anthropology textbooks for the last few years. She said she was passing along an email from a student who used Our Origins, the first Norton book I worked on, and that the student had "high praise" for the online quiz material I wrote. I was pretty excited to open the document to see what the student had written, since I haven't really gotten a lot of feedback on my writing over the years. The sole mention of the quiz material was, "I also monitored my mastery of the material by taking the online quizzes." I'm sure there's high praise somewhere in that declarative sentence! I'm not complaining, though. I'm working on my fourth book (the second edition of Our Origins), so Norton's turned into a pretty lucrative and surprisingly steady summer paycheck. Yay for publishing houses turning out endless editions of textbooks!

May 19, 2010

That's Odd

I was talking to the isotope geochemist on my committee after we hashed out how to fix the strontium equation in my diss. He said, "I liked reading your dissertation. It's different than what we see in the hard sciences. But I get the feeling that it's odd." Odd? "Yeah, from the two committee members on the phone [Nic and Carole], it seemed like what you did was odd." Again, what was odd? That I wrote and defended a dissertation while also a new mother to an infant? That I finished my degree in 7 years, well under the standard for anthropology? "No, it's like it was odd that you did isotope analysis. Or that you studied skeletons. Or something. I was confused because it seems to me that archaeologists around the world are doing isotope analysis - we get dozens of requests a month."

Ah. The light went off. I explained that the combination of factors in my dissertation - the difficulty getting access to Roman skeletons, the need to be trained in both classics and anthropology, having to get by as best I could in my broken Italian, having to write and rewrite grant proposals for tens of thousands of dollars in grant money, and learning a crapload about archaeochemistry in a very short time - is what is odd. This approach, specifically chemical analysis of human skeletal remains from Rome itself, is new and different. It remains to be seen how my work will be received by the classics community, who are generally a bit suspicious about scientific approaches to the ancient world (and even more so if historical, cultural, and/or epigraphical data are not also engaged).

For better or for worse, though, I've taken on the incredibly broad topic of movement to Rome (voluntary and compulsory) and am trying to say something about the lives of those immigrants. I come down strongly on the side of "osteology can tell us more about a person than a tombstone can," but many, many classicists are not on the same side. So I'm trying my best to get this dissertation out before the end of the month, because I'm curious to see what life my ideas will have outside of my brain and my dissertation.

May 18, 2010

Just when I thought the Sr was done...

It seems my Sr mixing model equation for Rome was wrong. I didn't take into account the Sr concentration of the two sources (aqueduct water from the Monti Simbruini in the east and aqueduct water from the Colli Albani), just the relative abundance of water in the mixture. So I hung out with an isotope geochemist for the better part of an hour today and got a better equation. What it showed was that, even though two-thirds of the aqueduct water was coming from outside of Rome, because it has a very low strontium concentration, its contribution was being dwarfed by the local water, which is strontium-rich. Basically, if a person was drinking more than 10% of their water from sources in the Colli Albani, their strontium isotope ratio will be indistinguishable from someone who drank 100% of their water from the Colli Albani.

What this means to me is that, in all likelihood, the strontium range of Rome is much narrower than I thought, perhaps .7090 to .7100 as suggested by my other mixing model. However, I cannot rule out the possibility that there were people living in Rome or the suburbium who got all of their water from the eastern aqueducts. It seems that aqueduct water was not generally mixed at Rome; that is, public fountains, castella, baths, and private houses were fed by one aqueduct. We know a lot about which aqueduct fed which part of the city or which fountain/bath/castellum. As the strontium ratios I measured are from first molars, they reflect an average over the first 3 years of a person's life - the time when a Roman was least likely to be independently mobile. So, if a person grew up in Rome near a castellum (a reservoir that his/her parents drew water from) or lived in a villa that was supplied by the eastern aqueducts (Anio Vetus, Anio Novus, Claudia, and Marcia), that person could easily have gotten over 90% of his water from the lower-Sr sources. Similarly, if a person grew up in the suburbium in a villa that illegally tapped the aqueduct (which was quite common), that person might have a lower Sr signature.

Since I can't rule out the possibility that people living in Rome could have obtained significant amounts of lower-Sr water, this doesn't change my identification of immigrants or my dissertation conclusions. I still need to posit a very conservative Sr range for Rome. Should I ever get more Sr ppm data, I might be able to narrow down the local range at Rome, thereby identifying people who probably came from Campania, which has slightly lower Sr isotope ratios than Rome but similar oxygen ratios.

May 12, 2010

Roman Volcanoes

A colleague in Iceland told me that the recent eruption of the Eyjafjallajokull volcano created a problem for livestock farmers. Their animals were eating plants and drinking water covered by the fine ash, which was high in fluoride. Excessive ingestion of fluoride leads to dental fluorosis as well as skeletal fluorosis. Fluoride is a regular byproduct of volcanic activity, so it stands to reason that fluorosis was actually a common problem particularly in the late 1st century Italy, following the eruption of Vesuvius. I don't actually know how soon people began farming the land around Pompeii and Herculaneum or how far the ash cloud spread. But fluorosis should be a relatively easy thing to spot in ancient skeletal remains, even if it can get confused with DISH (diffuse idiopathic skeletal hyperostosis). As far as I can tell, there is one publication on dental fluorosis in ancient Italy, on some skeletons from Herculaneum, in a letter to the editor of the Lancet in 1995 (Torino et al., vol. 345, p. 1306). Excluding the table, the entire thing reads:

Dental fluorosis in ancient Herculaneum

"Sir - Excavations of the arches surrounding the beach of Herculaneum (the ancient Roman town buried with Pompeii by the eruption of Vesuvius in AD 79) revealed whole skeletons of some hundreds of victims. The ancient Herculaneans enjoyed an excellent and very cariogenic alimentation, chiefly based on fish and meat with large amounts of honey. However, only 49 (3-8%) of 1275 teeth from 41 adults and 12 children were carious. This percentage is very low for both modern and ancient populations, in which values were between 8-5%, as in classic Magna Graecia/ and 11 -4%, as in Roman Britain. In fact, in the Herculaneum skeletons we showed in a high proportion of individuals (14 of 48, 29.2%) enamel hypoplasia due to alterated amelogenesis, which is often caused by starvation or other types of stress but is also common in well nourished people subject to chronic fluorosis. These data strongly suggested the presence of some cases of dental fluorosis. To elucidate this hypothesis, we examined thin sections of permanent teeth enamel (first molar) from 8 individuals found in the Herculaneum arches site and from a present-day patient from Pisa without evidence of fluorosis, as control. Enamel was analysed by energy dispersion system (EDS) with an SEM (Jeol) 6400 connected to a microanalysis system (EDS) (Noran-Tracor) with a detection of Z-MAX 30. The following results were obtained (table). Enamel fluorine concentrations were greater than 10-fold higher than normal (1500-3600 parts per million [ppm]) were recorded in 6 individuals (table). However, in an adolescent girl and an adult woman, fluorine was not detectable. Furthermore, the absence of fluorine in the soil excluded any contamination.

Together with the finding of very few caries and the high frequency of enamel hypoplasia, these results clearly demonstrate the presence of endemic dental fluorosis. These findings are lent support by the strong concentration of fluorine in the water-bearing stratum of Herculaneum (3-8 mg/mL), with a calculated intake of 11-4-19-0 mg a day per person at the time of the volcanic eruption. Members of the Roman aristocracy had villas in Herculaneum, so perhaps some of our subjects were visitors to the region."

I stumbled upon this idea while brainstorming ways that immigrants to Rome might be less healthy than locals (other than lack of immunity to endemic diseases). If people stuck around after the eruption of Vesuvius in 79 AD, then decided to journey north to Rome, they might have come with skeletal or dental fluorosis from ingesting too much fluoride. I doubt dental fluorosis results in poor health outcomes, but I suspect skeletal fluorosis would at the very least make someone more susceptible to development of osteoarthritis. If only I had graduate students, I could make one of them research fluorosis in late 1st century AD Italy for a thesis or dissertation!

And this is why I had to stop myself from following up every citation that piqued my interest while dissertating... what should have been a simple clarification of how immigrants tie into the epidemiology of the Roman population has turned into two hours' worth of reading about fluorosis.

The Other Dr. K

When I was in 6th grade, my math teacher, Mr. Roberts, had this poster in his classroom. It was of a sports figure that I had never heard of and read, "Dr. K says: Get an A - make it a Major League year!" The phrase stuck with me all these years, perhaps because I never knew who Dr. K was or perhaps because 6th grade math was interminably boring because it was so easy. (That said, that was the year I realized that I was a very haptic learner, as I'd failed spectacularly in my zeal to create my own method to use in multiplying and dividing fractions. It was also the year that a certain someone kept beating me on the Mad Minutes, for which I would not forgive her until high school.)

Because I have a ton of work to do, I found myself googling this morning for the phrase that's been popping in and out of my head often since I became Dr. K. I cannot for the life of me find evidence that this poster ever existed. However, I did learn that Dr. K is the nickname of the former baseball player Dwight Gooden. He was an impressive pitcher for the Mets for a decade, earning the nickname because K is the standard abbreviation for strikeout (and on analogy with basketball's Dr. J). At some point, Dr. K must have been famous enough to convince kids that hard work at school was important. By the time I was in 6th grade, the year was 1988-89 (unless my math is wrong, and Mr. Roberts can correct me). In early 1987, Dr. K got into trouble with police, and that eventually led to the Tampa Riots of 1987. At spring training the same year, he tested positive for cocaine.

Dr. K did return to baseball to play until 2000. But I wonder if Mr. Roberts didn't know about Dr. K's drug problem. After all, there wasn't the 24-hour news cycle that there is today, nor were athletes the super celebrities they are today. Or maybe after years of being in the same classroom, the poster just escaped my math teacher's notice. It seems odd to me that a motivational poster would stay on the wall after its subject was found to be the wrong kind of role model for kids. But I could be applying today's "moral" standards (e.g., an athlete's losing endorsements simply because he had sex) to the athletes of decades past.

At any rate, if anyone can confirm for me - with an image or with random recollections from 20 years ago - that this poster existed with this phrase on it, the brain cells that are being wasted on this memory would be most grateful.

UPDATE: And the grand prize of one million googles goes to Lynn Heath, who quickly found an eBay auction of the poster. Unfortunately, the auction has ended, or I might just buy it and put my own mug on it to terrify future osteology students.

May 9, 2010

Darwin's Tubercle (or Happy Mother's Day)

I learn new things every day, not just as a researcher but also as a mother. I'm especially geeked out when those two worlds collide. After Chickpea was born, I would joke that the only thing this blonde, blue-eyed kid inherited from me was one ear. We both have a little bump on the outer ring of cartilage on the right ear. I'd never noticed, but when I told my mom, she mentioned that she had it too. It was pretty cool to find such an obviously inherited trait, but I thought it was just random ear morphology.

Turns out, there's an even cooler name for it: Darwin's tubercle. At the beginning of Descent of Man, Darwin apparently pointed out this extra bit of flesh on the helix of the ear as a homologous trait between humans and primate ancestors, the remnant of a once-pointed ear. A Spanish anthropologist found in the 1980s that it was present in 10% of the population surveyed in Madrid, but I don't know if the frequency varies based on ancestry. I also don't know if it's usually bilateral or asymmetrical - in my family, it's the latter, although curiously I think my mom has it on her left ear, but Chickpea and I have it on our right (as you can kind of see in the picture above, even though my hair often covers my right ear).

Wikipedia claims that the auricular tubercle has been associated with royalty, both in humans and in other primates. While I doubt the veracity of this claim, Chickpea does seem to think that her sole duties in life are to be fed, clothed, loved, and entertained by her mother. Fortunately, I don't mind treating her like royalty.

May 5, 2010


After 10 years of graduate school (on top of 4 years of undergrad and a bunch of grade school), I guess I'm done. Everyone said it would be anticlimactic, and it was. My talk went fine - no glitches in the conference call, Skype, or Mikogo. There were nerves, of course, but it definitely could have been worse.

Afterwards, I fielded questions from the audience; there wasn't anything that surprised me or hadn't been asked of me before at some point. I should take Mark's suggestion (which Patrick had suggested a few days before) of a mathematical way to weight the differences in disease between locals and immigrants to see if any more statistical differences are there. We moved the closed defense to a smaller conference room, and I broke out the bribes: cake pops and rice krispie cheese crackers that my darling husband had cooked the night before. (Plus a bunch of cans of Kroger's house-brand Dr. Pepper, which is called Dr. K. The joke was appreciated.)

For those of you interested in what goes on behind closed doors in the defense... I mostly just babbled about isotopes and skeletons and slavery, since I'm not terribly good at thinking and answering on my feet (and therefore why I'm glad I'm a good writer).

Carole wanted to know more about my thoughts on slavery in the Roman Empire. It's not something I had given a lot of thought to, at least not in terms of what I could do to move that research stream forward, because I have only just grazed the surface of the primary and secondary literature on the topic.

Nic wanted me to talk more about heterogeneity and the lack of a one-size-fits-all "Roman" experience, particularly in light of the fact that much of our knowledge of Roman culture comes from the elite. This is something I need to think about in terms of what makes someone "local."

Drew picked up on that and wanted me to talk about how isotopes tell us someone is local and how they might be wrong. He also tried to get me to explain the mathematical error with one of my mixing models, which he introduced by saying, "I'm going to pretend this is a geology defense rather than an anthropology one." Eek. Math is, as Patrick can attest, not my strong suit, even though I wanted to be a mathematician when I was in elementary school. So I flubbed that response miserably; but I do now understand where I was wrong and how I can fix it, which should be pretty easy to do.

Margie and Dale pointed out that the fact that 6 immigrants were 11-15 years old is quite interesting and that I shouldn't back away from some of my interpretations as much as I do. Margie also thought I should look further into differences between the immigrant/local populations at the two sites, since I mostly talked about the pooled populations and individuals: so looking at the level in between would be instructive.

Dale further suggested that there might be a specific time post-immigration that is best for finding immigrants. That is, there is some evidence that enamel (or, at the very least, dentine and surface enamel) uptakes Sr in vivo, so immigrants who have lived in Rome for 20 years could very well appear to be Roman from isotopes. Since I found a lot of immigrant kids, it could mean their enamel is "fresher" - that is, more likely to show immigration because of fewer years of possible Sr uptake. Looking into this from a methodological standpoint, though, would likely require an additional research study with some amount of control over the subjects.

Dale and Drew both really liked the dietary data that indicates immigrants changed their diet upon arriving at Rome: Dale, because he pushed me to do diet even though I didn't want to, and Drew because it confirmed for him that at least 4 people I'd identified as immigrants from Sr/O were indeed immigrants. I was happy that my ingenuity in comparing the bone/enamel carbon values was also appreciated by my committee.

I think both Nic and Carole basically asked me how I would push this research if I had unlimited money and 10 years. I probably mumbled something about isotopes and sampling the Empire, but when I told Sara about this after the defense she said, "Unlimited money? I would build a time machine and go back and ASK the slaves what they thought." That was a better answer than mine.

That's pretty much how it went. I got some good ideas from everyone and some compliments on my research. Many of the comments I can deal with during revisions, some I will just have to keep in mind for the next project. I'm taking a few days away from the diss to deal with the things I've been putting off for weeks, but next week it's on to revisions and submission. As soon as I submit it to the Grad School, I'll post the diss online so everyone who wants to read 400 pages about immigration to Rome can do so.

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