May 30, 2014

Roman Bioarchaeology Carnival XLI

It's still pretty quiet in the world of Roman bioarchaeology, but I keep thinking this'll change as soon as summer excavations start trumpeting their findings to the news media, maybe around August or September.  Until then, I'm stretching the time-period of "Roman" bioarchaeology a bit to bring you some interesting news...

New Finds and Theories
  • 13 May - "Mummified fetus found in tiny ancient Egyptian sarcophagus" (Discovery News). A tiny sarcophagus from about 600 B.C. was long thought to be some sort of fake, but a new CT scan has revealed a fetus of about 12 to 16 weeks' gestation. Iconography is consistent with male individuals, but DNA analysis of the fetus hasn't been done to confirm.
Worsley Man (credit: Manchester Evening News)
  • 16 May - "Groundbreaking scan reveals evidence of ritual human sacrifice... in Salford [UK]" (Manchester Evening News). So-called Worsley Man's head was found in a bog in the 1950s.  He's thought to date to about 100 AD.  A recent 3D CT scan found a sharp, pointy object in his neck, which archaeologists seem to think was a ceremonial spear.  His injuries also included lots of blunt trauma to his head, and he was strangled and decapitated.  Not sure why this is "ritual human sacrifice" and not "someone did some nasty things to this man." 
  • 27 May - "2,300-year-old false tooth removed in northern France" (The Guardian). The headline is kind of nonsensical if you read it too many times, but it seems a burial of a woman was found in which she had an iron post placed into a tooth socket after her death. Kind of cool to see some postmortem dentistry, though, in pre-Roman times.

Articles (New and Newly Online)

Blog Posts

May 29, 2014

An Ancient Roman in Pre-K

This is the last week of school for the kiddos in Pensacola.  My daughter Cecilia's pre-Kindergarten class put on a little show last night for their end-of-year International Day, complete with parade, songs, and a potluck for the families.  When the announcement was circulated last month, we were asked to pick a country, make a flag, and help our kids dress up as someone from that place.  Rather than selecting one of the many ethnicities that make up our family (primarily Russian on my side, and Greek/English on my husband's), I convinced her to be from my adopted culture -- Ancient Rome. Besides, we already had a little gladiator-esque costume that I picked up from Caesar's Palace (of course) in Las Vegas a couple years back (I got the "boy" costume because the "girl" costume was a really boring white sheath), and my kid already has Latin-inspired praenomina (Caecilia Livia) and cognomen ("Chickpea," which is where the name Cicero comes from and is also based on the Italian nickname Cece).  We even printed out the SPQR standard for her flag.

Eat like the Romans eat!
The potluck snuck up on me, though, and I realized that I was supposed to bring a culturally-appropriate food item.  So, how to make the Mediterranean triad appropriate and appealing to kids who are probably not as adventurous about food as Cecilia?  Here's what I came up with:
  • Homemade focaccia
  • Olives (I only had Spanish olives in the pantry)
  • Simple chickpea salad (toss with diced onions, parsley, olive oil, vinegar, salt and pepper to taste)
  • Grapes
  • Provolone (figured the kids wouldn't eat parmigiano reggiano, which is probably the closest to ancient Roman cheese we have today  
A hearty enough meal for even the most exhausted miles or gladiator! Other than the grapes, I had all the ingredients as staples in my kitchen.  Clearly, my tastes are influenced by Mediterranean cooking.

The kiddos had a great time showing off for their parents and siblings, and we all got to try delicious food inspired by other countries and cultures.  And the Mediterranean triad?  Almost all of it was gone by the end of the evening.

May 28, 2014

Are Osteologists’ Demographic Assessments Biased by Outside Context?

A Powered by Osteons reader, Judy Barr, alerted Kristina Killgrove to a new article in the journal Science and Justice called “Cognitive bias in forensic anthropology: Visual assessment of skeletal remains is susceptible to conformation bias” by Nakhaeizadeha, Dror & Morgan. Kristina then posted it to BioAnthropology News (if you’re not a member, click on the link and join!), and got into a back-and-forth with fellow bioarchaeologist Alison Atkin, who also writes the Deathsplanation blog.  We decided to try something new: opening up our ideas by cross-posting our conversation on our respective blogs.
The article is open for anyone to read (click link above), but boils down to the idea of priming: that a person’s response to a stimulus can be affected by another stimulus. An example from marketing: if you go to the grocery store and see that breakfast cereal was originally $2.99 but is now marked down to $2.49, you’re more likely to buy it than if the store simply labeled it as $2.49 to begin with.  In this article, the authors “prime” a subject pool by giving them true, false, and no additional context about a skeleton to see if the extraneous context biases their forensic opinion about the demographics (age, sex, and ancestry).

Kristina Killgrove: I’ll kick this off with my initial interest in the article, prior to fully reading it.  This is not a journal I regularly read, let alone was even aware of, but my first impression was that the article is overly critical of osteological methods of assessing sex. Given a complete, well-preserved skeleton, we can be about 95-99% confident of our sex assessment, but given incomplete remains, particularly from an archaeological context, that accuracy drops. Due to the article’s placement in this journal, though, it is clear that the authors want to raise awareness of the shortcomings of osteological demographic analysis because of its relevance to forensic cases and possible (in)admissibility in court.  There is a lot of misunderstanding about forensic anthropology, due to factors like TV portrayal of the field in Bones or CSI and due to the widespread ignorance of science in the U.S., so my interest was piqued by the article’s title and the abstract.  What was your first reaction to the article, Alison?

Alison Atkin: I think my first reaction of the article was quite similar to yours - although perhaps a bit more unprofessional. If I recall correctly, it was something along the lines of, "How dare 'they' question the reliability of this science to which I dedicate my life." The osteology and biological/forensic anthropology community over here (in the UK) isn’t enormous. So, given the topic of this study, I was surprised that I wasn’t familiar with the authors of the study - however after fully reading the paper, it became clear why non-(osteology)-specialists were interested in this area of research.

My initial skim-read of the article produced a lot of questions on various aspects of the study. While I feel very strongly about osteology being a fantastic scientific discipline, I am aware that it has its fair share of methodological problems. However, this paper felt really unbalanced (and not in our favour). Although my initial reactions were probably in defence of my discipline, after looking more in-depth into the issues I had with this study, I think most of them were justified.

Nakhaeizadeha et al. 2014, Fig. 1 -- The skeleton used in the study
KK: Well, I’ll admit that I also had some knee-jerk reactions upon skimming. But I moved on to the methodology section, because I was genuinely curious about the way the authors set up their study. Unfortunately, I can’t fairly assess the methodology because the authors don’t give enough relevant information.  My main issues/questions about the study are:
  • They don’t fully discuss which portions of the skeleton were available for study. Was the pubic symphysis -- by far the best portion of the skeleton for accurately estimating both age and sex -- present or did the participants rely on less accurate techniques?
  • The skeleton was archaeological, not forensic, and the participants didn’t know this. This context -- bioarchaeological or forensic -- is very relevant for completing a full demographic profile because some methods may be affected by secular or cross-cultural differences in populations.
  • The participants were largely students. Students outnumbered professionals (using the terms of the authors) 2 to 1.  In the control group C, the students outnumbered the professionals 3 to 1.  This makes it impossible to control for experience in assessing bias. (I have nothing against students, of course, since I was one just a few short years ago. But I am also certain that I am better at my job now than I was then.)

This is not to say that the topic of the paper is bad; in fact, I am actually worried that context may bias osteological analysis. This isn’t a big deal with archaeological remains generally (if you use grave goods to bias your opinion about sex, it’s not the end of the world), but it gets more complicated when you are talking about forensic evidence admissible in a court of law. I’ve worked a few forensic cases as an assistant, and for most of them, I knew the context of the remains; that is, I knew the demographic details of the person the police thought they’d found. I do worry about cognitive bias, as the authors call it, but they did not design a robust study to test for it because it’s impossible to separate correlation and causation in their methodology.

Did you have similar concerns?

AA: I did. I was really surprised that the exacts methods used weren't stated in the paper. As someone who is used to controlling for bias in my own research I am all too aware that certain methodologies are either more or less reliable than others and some can be difficult to apply if you are unfamiliar with them (even if you have handouts - such as those provided to participants in this study). If you tried published a similar paper in a more bioarchaeology-related journal, without stating which methods you used, I am pretty sure it wouldn't pass review. It would be very difficult to replicate this study without knowing this information (although you could of course conduct a similar one).

In addition to the points you've mentioned there were some other aspects of the study methodology I am curious about:
  • Participants were from different fields. In the UK, osteology and forensic anthropology are different disciplines. We learn the same information, but the aims of our investigations are very different. I wonder if all of the participants would have been considered qualified to stand as an expert-witness in court, given the main aim of this study?
  • DNA analysis of sex is a unique biasing factor. I was curious about the decision to include DNA results with sex-specific markers (the authors used the word gender, but we won't get into that here). It is very rare that you see DNA used to determine sex in archaeological material - and it would always be done after the skeletal assessment. Using both precise methods (like DNA analysis) and less precise methods (like skeletal markers) to form the false contexts would likely have provided different levels of bias for different aspects of this study.
  • Could participants answer probable male/female? The archaeological skeleton in this study was recorded in the database as 'probable female'. The authors stated they are especially concerned about bias in ambiguous cases - however as far as I can tell, participants only had the option to state at the end of their assessment whether the individual was: male, female, undermined - and not probable male/female.

Given the issues I had with the methodology of this study, I really wasn't surprised to see many of the results. But, like you, I'm not sure the interpretations drawn from them are necessarily that robust. Is it worrying that papers like this which, while interesting appear to be flawed, may have an impact on the admissibility of biological anthropology in court cases?

Speaking of the results, shall we give a quick run-down of what they found?

KK: There’s a whole mess of chi-squaring and some terrible bar graphs going on, but sure. Here goes, keeping in mind the skeleton is archaeological (from England, so most like today’s Caucasian population), probably female, and late 30s to early 40s:
  • Sex (Probably Female)
    • Group A (male context) - 71% said male, while 29% said female
    • Group B (female context) - 100% said female
    • Group C (no context) - 30% said male, while 70% said female
  • Age-at-Death (36-45)
    • Group A (25-30 context) - 0 at 18-25, 11 at 26-35, 3 at 36-45, 0 at over 46
    • Group B (50-55 context) - 0 at 18-25, 1 at 26-35, 7 at 36-45, and 5 at over 46
    • Group C (no context) - 1 assessed 18-25, 6 at 26-35, 5 at 36-45, and 1 at over 46
  • Ancestry (Caucasian)
    • Group A (Caucasian context) - 100% got it right
    • Group B (Asian context) - 50% got it right, 29% said Asian, and 21% didn’t know
    • Group C (no context) - 100% got it right

On my initial read, I wondered why ancestry had such high numbers; the vast majority of the people in the fake-context Group B either got the ancestry right or said it was indeterminable. But when Alison pointed out that the fake sex context included DNA, it started to make more sense. As for the age-at-death, the authors kind of punt on explaining this, choosing instead to refer the reader to a terrible graph (people: if you’re going to do color graphs, pleeeeease change the texture of each color so that people who print them out or who are colorblind can tell them apart! Also, spell-check your axes...).  I think the weirdness here may have to do with the non-standard (for the US anyway) age ranges, the odd precision of the ranges, and the context given.  But I’m more interested in hearing what you have to say, Alison, since you know way more about age-at-death methodologies and their biases than I do.

AA: Ha, so I’m not the only one with an editing hat who caught that graph-error. Blatant.

With regards to ageing, it’s really difficult to say much without knowing which methods were actually applied (have I said that enough yet?). The paper says that the participants were given access to visual aids for ‘the majority of all non-metric assessments available for each stage [meaning age, sex, ancestry]’, which were taken from Museum of London (MOL) documents - however, does this mean the participants were ageing using the pubic symphysis, cranial sutures, the auricular surface, tooth wear, maybe rib ends…? Many of these methods are accurate (and many are not), but they all have their issues.

When it comes to the age categories, the ones presented are pretty narrow (at 10-year intervals) but this is not unusual. There are no standard age categories - different institutions will use different age categories. This study says theirs were ‘adapted’ from the MOL ones. Personally, I’d be okay with using narrower categories if they were divided a bit differently, like: 15-19, 20-24 (because younger adults can be aged a bit more accurately) and then maybe 25-34, 35-49, 50+. But sometimes you see it as broad as: Young Adult (20-34), Middle Adult (35-49), Old Adult (50+).

That older individuals are consistently under-aged in osteology is a well known fact and it has been something that osteologists have been trying to solve a very long time, so I’m not surprised this paper found results indicating this was the case.

I have to stop and ask at this point - am I the only one wishing they’d published the results of how confident the participants were with their final assessments? I mean they bothered to ask this as a part of their ‘ruse’ (perhaps not the most fair word, but I’m using it), so why not share the results?

KK: No, you’re not alone. I was especially interested because the authors gave a forensic scenario but didn’t specifically note if this was a “court of law” type of scenario.  If I were assessing demographics for an archaeological case, I actually think I would consider myself more confident than if I were assessing a forensic case for a murder trial. The methods and their shortcomings are the same, but forensic anthropology is a much more practical, applied use of the techniques--and can literally be a matter of life and death.

And that makes me wonder about the broader implications of this article.  If osteologists can be biased by (false) context, will we see a change in the admissibility of forensic evidence in court?  In the U.S., we already have the Daubert Standard (and facial reconstruction is one of the forensic techniques that does not meet it), but I think the interpretation of “scientific knowledge” and “scientific method” could be open to interpretation, especially if osteological techniques can be biased by external factors.  Thoughts?

AA: I definitely think that it is something that needs to be considered - especially in forensic cases. The authors’ final conclusions, that context can bias results, is almost certainly true (at least in part). But, I do think that there are steps professionals can take to mitigate these effects - first and foremost of course, is being aware of this risk (something students are routinely taught). The authors state that more research is needed before recommendations can be made - but surely they could have at least made some suggestions.* Without them the study appears to have very damning conclusions for the use of osteology in courts.

I am worried that this study and others like it could potentially be used in a legal scenario to throw doubt on to the results of a skeletal assessment - when as we’ve just discussed, there are some pretty big issues with the study. Provided the expert witness in court gives details of the methods they use in their assessment, evidence to support their reliability, and present their results to the degree that their confidence allows then I can’t see a problem with continuing to use them.** Every science has its issues, but being aware of them can make all the difference.

I think if more studies of this kind are conducted and recommendations put in place to account for that dreaded ‘cognitive bias’ then it will only make our discipline stronger. It will also benefit archaeology as well - imagine no more females with swords being mistaken for their male relatives!

KK: My final thoughts on this study are similar: the authors seem to think they’re the first to have considered this.  And perhaps they are, from the specific angle of cognitive bias, but osteological specialists have been doing replicability studies for decades.  To cite but one recent example, Ashley Smith and Amelia Boaks have a forthcoming article in the Journal of Forensic Sciences about validating postcranial landmark locations. Why something as seemingly mundane as the locations from which we measure bone?  Because measurements are used in stature estimations, sex estimations (e.g., femoral head diameter), and ancestry estimations (e.g., FORDISC). Smith and Boaks found high consistency in some measurements, but those percentages still ranged only from 55-62.3%, with differences of tens of millimeters!  They discuss these findings in light of Daubert and the need for better standardization.  

There are dozens of other references like these, which all lead to osteologists creating better handbooks and better standardization.  The revolution in digitization, I think, should obviate some of the inter-observer errors, but this is slow in coming to anthropology.  My point is that osteologists themselves are doing this kind of analysis, and it’s odd for outsiders to devise a poorly-created study to do it.  Not that there isn’t a reason for outsiders to try, especially when it’s related to cognitive bias, but these just didn’t succeed.

Alison, any final comments?  I’ll leave the last word to you.

AA: Well, I was going to sum up with this: We absolutely need address biases in the application of various methodologies in skeletal assessments. In order to do this, we must first understand these biases - and determine the factors that impact their effect on results. While I am not convinced this paper has done a great deal to assist us in doing either - understanding or addressing these biases - I will be very interested in future studies that do. So let’s hop to it osteologists…

But instead I think I’ll go with: Please make sure you include all of the details of your study methodology in your published papers. Sincerely, an academic osteologist.

Buikstra, J. and D. Ubelaker. 1994. Standards for Data Collection from Human Skeletal Remains. Arkansas Archeological Society.
Nakhaeizadeh S, Dror IE, & Morgan RM (2014). Cognitive bias in forensic anthropology: Visual assessment of skeletal remains is susceptible to confirmation bias. Science & Justice : Journal of the Forensic Science Society, 54 (3), 208-14 PMID: 24796950.

Smith, A.C. and A. Boaks. In press. How “standardized” is standardized? A validation of postcranial landmark locations.  Journal of Forensic Sciences.

Thanks to Ashley Smith for sharing a pre-publication version of the JFS article.

*For example: Conducting skeletal assessments ‘blind’ (not being provided with any contextual information apart from the period the remains date from - as this can influence the reliability of certain methods).

**For example: Based on the non-metric analysis of the os coxae, which showed good preservation allowing for a full assessment, these methods were used of scoring these skeletal indicators (sub-pubic angle, sciatic notch, etc). Peer-reviewed studies have shown these methods to be accurate up to 98% in correctly identifying the biological sex of an individual (provide relevant citations). I estimate, based on the results of these methods that this individual is a probable female. This suggests, given the different categories of classification of biological sex within an osteological framework that it is most likely these skeletal remains are from an female individual. BAM!

May 19, 2014

Bones - Season 9, Episode 24 (Review)

The Recluse in the Recliner
Episode Summary
Booth gets a call on his secure line from someone who wants to meet, who has information about the MacNamaras. When he gets the call traced, he finds out the fire department is already there -- the person exploded in a mobile home, and parts of the body are fused to the vinyl. At first glance, it looks like the person drank heavily and then passed out while smoking, combusting. Brennan finds a zygomatic process and concludes the person was Caucasian; she doesn't ever determine sex, but she refers to the person with male pronouns. Booth notices that the circuit breaker is fused in the off position, making him think it was not an accident. Someone knew the man had something to tell Booth and didn't want him to.

At the Jeffersonian, Fisher estimates from the pubic symphysis that the victim was in his mid-30s. A facial reconstruction done using Angela's magic software on shattered bone gets her a hit: Wesley Foster. Saroyan looks at Foster's lung tissue and concludes he did not die of smoke inhalation. Foster was a journalist but then got all conspiracy-theory-nutty, lost his job and his wife, and started working as a janitor at Cryus Security, which was owned by the MacNamaras. Brennan, meanwhile, finds perimortem chipping to Foster's teeth which she thinks happened when he had a tube or funnel forced into his mouth. Fisher thinks he may be able to swab and get epithelial cells from the killer. 

Angela is upset that the killer took Foster's hard drive, but Hodgins reminds her that conspiracy-nutters would have a backup somewhere. While picking through body debris in the trailer, which has been installed at the Jeffersonian, Fisher finds Foster's nipple and Hodgins notes that the material the nipple ring is made out of is not normal: it's a memory chip. Perimortem fractures to Foster's 8th and 9th ribs and sternum suggest someone aggressively tried CPR; Brennan thinks that Foster was being tortured for information. Angela gets much of the data off the chip, and it includes bank records, confidential email, photographs, and all manner of compromising information. Booth recognizes a photo as one he took; Angela finds out that the girl in the photo, who was shooting up, was the daughter of a senator. Booth had been lied to about the reason he needed to take the photo. 

Saroyan finds epithelial cells from three different men on Foster's body.  While she can tell their sex and their race, she does not get a hit in a DNA database. Brennan notes that there are no ligature marks on Foster's body, which means two of the men held him down while the other tortured him. Fisher thinks that the fracture to the third cervical vertebra feels odd; Brennan recognizes it as a take-down strangle-hold used by Delta Force operatives. Although their DNA is erased from the system, Saroyan thinks she can work backward to find out which operatives' information was erased. Hodgins finds a fragment of Delta Force watch band in the vertebra.

Booth, meanwhile, is in front of the congressional hearing to appoint him as head of the German branch office. Everything is going smoothly until Congressman Hadley, with whom Booth had had lunch the other day, turned on him and asked about his killing of a U.S. citizen in Pakistan in 2006. Booth is caught off guard because that was highly classified information and he is not allowed to even respond to the charge. He and Brennan run past the press, and Stark puts him on administrative leave. Booth packs up his office, but he also approaches Hadley, who he found out is gay from pictures Angela found on the nipple-ring-memory-chip. Hadley then calls a burner phone to relay Booth's assertion that he won't give up.  Angela traces the call and realizes they're sending the team out to dispatch Booth. Brennan takes Christine to Max's while Booth puts explosives around the house. Fisher finds out from Foster's wounds that two of the Delta Force guys are right-handed and one is a leftie.  He tells Brennan this, but she realizes she can't call Booth.  There's a giant shoot-out at Casa de Booth & Brennan, and Hodgins manages to get the rest of the goo off the nipple-ring-memory-chip and the team finds out that the three judges who prevented Miss Julian from getting a warrant are on the chip. 

Booth manages to kill two of the Delta Force operatives but gets shot so is struggling with the third because of his injuries. Brennan shows up, since she thought the handedness information might be relevant, and shoots the third.  He doesn't die and comes for Brennan; Booth gets him down and breaks his neck, though. Booth codes on the table in the OR, but the medical team brings him back. Brennan sneaks in to see him in recovery and notices he is handcuffed to the bed.  Stark asserts it is because Booth killed three FBI agents for no good reason.  And that, folks, is the Season 9 cliffhanger!

  • Forensic/Plot
    • Yeah yeah, didn't figure out sex from the bones, got race from a teeny fragment of one bone, but at least the pubic symphysis seemed right.  Oh, and Angela's facial reconstruction match was beyond crazy.
    • I thought Foster died of a heart attack?  (Hence the failed attempt at CPR.)  Why did one of the Delta Force guys also break his neck?  Seems unnecessary. (If the guy's watch band was embedded in the bone, I can't imagine it's not fatal.)
    • If the Delta Force guys' DNA was erased, wouldn't all of their info be erased?  So unless Saroyan has printed records of all the Delta Force names, I don't see how she can work backward to find them. (Could be moot; seems Stark may know who the agents are.)
    • Why weren't any of the three Delta Force operatives wearing gloves to torture and kill Foster?  That's, like, Bad Guy 101. I mean, they were fully suited up to get Booth.
    • Sooooo, how long does it take for the police to get called to a shoot-out in a nice neighborhood?
    • But hey, kudos to the writers for making me write "nipple-ring-memory-chip" repeatedly.

Forensic Mystery - B. There was a lot going on, and the mystery is still mysterious, but the plot definitely seemed overwrought. 

Forensic Solution - I. (Well, I give students who don't finish all of their work for my classes an incomplete for a grade.)

Drama - B+. You knew Booth wouldn't die, but the handcuffs at the end were a nice touch. I might actually be interested to see how this resolves next season.

Well, thanks for sticking around for Season 9, dear readers.  I think Season 10 is supposed to be the last, so I might as well see this through to the end.  As with this season, though, I may post late because of work and life and such.  But I'll be back in the fall when Bones comes on again.  Have a good summer!

May 16, 2014

Bones - Season 9, Episode 23 (Review)

The Drama in the Queen
Episode Summary
A candidate for mom-of-the-year tries to convince her 6-year-old to hang out in a well so they can get famous when she's rescued.  The mom goes down instead and finds a skeletonized body.  The well is in Ellicott City, Maryland, but there's no indication as to why the FBI needs to get involved.  Still, Sweets is leading the investigation because apparently that's what he does now in addition to being a wunderkind psychological profiler.

I could have picked a number of different pictures of
this episode, but... hot swimmer bod. You're welcome.
Hodgins finds blowflies and flesh flies, suggesting time of death was about 5 days prior. The size of the femoral head tells Brennan the victim was male, and the lack of marked lipping on the dorsal border of the pubic symphysis leads her to estimate he was in his early 40s. The bones are encrusted with coins from having come into contact with the bottom of the limestone well.

Back at the Jeffersonian, Brennan complains that she cannot tell perimortem from postmortem injuries because of all the coins adhering to the skeleton. The new intern, Jessica Warren, notes that the greater and lesser tubercles of the humeri are enlarged, as are the heads of both femora. Irregularity in the coracoid processes of both scapulae suggest a strain in his upper arm muscles, so Warren and Brennan think he may have been a swimmer. Saroyan doesn't find any drugs on the tox screen.

Angela gets a hit off the missing persons database: Brian Thomas, 43, a swim coach at fictional Knox Community College in Maryland. His wife, Lila, reported him missing but isn't sure when she saw him last because she works nights and he spent long hours at the pool. Brian reported some of his students for hazing, so Brennan and Sweets head to the pool to question Avery Parish. Parish has asymmetrical posture from limited mobility in his glenohumeral joint, or swimmer's shoulder. His friend, Quentin Marks, has poor hearing, which Brennan thinks is from prolonged exposure to pool water. Both are getting scholarships to four-year universities because of swim team.  Another female swimmer suggests that Coach Gabby Morrell may have been sleeping with Brian Thomas. She denies the affair but thought that Brian may have been having one since she smelled perfume and found a gaudy earring in his car when he drove her home. 

At the lab, Warren is working on removing the coins and staining from the bones so that she and Brennan can assess the injuries. Warren uses pineapple juice, which contains bromelain, to break down the proteins and remove the flesh. After doing that, she finds a fracture to the superior aspect of the acetabulum and another to the ilium suggestive of a fall down the well.  She also finds perimortem fracturing to the left humerus and to the posterior surfaces of the 9th, 10th, and 11th left ribs. Lumbar vertebrae 4 and 5 are also shattered, which would have caused paralysis. Further, the calcaneus seems to have been driven backward, causing chipping to the cuboid, suggesting a feet-first fall down the well. Bony enlargement at the end of the left 1st metatarsal shows a hallux abducto valgus deformity: a bunion. And a hairline Lisfranc fracture in the midfoot is often the result of someone stumbling over plantarflexed feet, as women can while wearing high heels. Osteophytes on the anterosuperior edges of vertebrae T1-3 show continued stress to the upper back.

Angela finds that Brian bought dinner every Friday night at the same place. No one there recognizes a picture of him, but Brennan and Booth realize what's across from the restaurant: a drag club called Madam's Apple. Brian was dressing as a drag queen every week; the osteophytes apparently resulted from the weight of his fake breasts. Brennan and Booth talk to the owner, Destiny Childs, who suggests Kimmy Moore was upset at Brian, who went by Jenny while in drag, for taking her spot. Kimmy denies it and shows that she wasn't in a fight; Brian's 3rd and 4th metacarpals show he had gotten a "fight bite" (NB: do not click that link unless you're ok with pus!) two to three weeks prior. An alloy of copper and zinc plus plastic in the wound lead the team to think Brian was hit with a pipe. Fortunately, Angela finds footage of the fight from the convenience store camera.  Brian, in drag, got into a fight with plumber Joe Rizzo.  Joe admits to the fight, which occurred when he accused Brian/Jenny of stealing his credit card information. Hodgins and Warren test their pipe theory with meat-and-gelatin puppets but get nowhere. Madam's Apple, Angela finds out, has free wifi, and when Sweets brings him in, the club owner Destiny Childs admits to stealing from his customers. But he had stopped several weeks ago.

Brennan and Warren continue to search for the murder weapon and cause of death. They realize that the injuries sustained were not blunt force but rather projectile trauma mimicking blunt force trauma because it occurred while Brian was in the pool. Bullets will slow and deform enough to mimic blunt force trauma at a depth of about 8 feet. He was likely shot with a hollow-point bullet from a .45.  At the pool, the team finds a nick in one of the lane dividers, which accounts for the plastic in the trace swab Hodgins did. Brennan finds traces of blood in a towel hamper that was likely used to move the body. They question Gabby Morrell again; she does own a .45 and has a key to the pool but insists she only uses the gun for target practice. When Hodgins finds a bullet fragment in the drain, it all comes together for Warren. She realizes that the killer had to have been in the pool with Brian. Water transmits more pressure than air, which means Brian should have a fractured ear ossicle; they fish out the stapes, and it has a hairline fracture. But this also means that the killer would have an ear injury and concomitant hearing loss.  Quentin Marks admits to the murder. His gun, a .45 he got after he was in the military, tested positive for gunshot residue and chlorine.  He apparently cheated on a midterm because his grades were slipping due to the time he was spending in the pool. Brian caught him and was going to turn him in, so he killed him because he really wanted to go to a four-year college.  

  • Forensic
    • This episode was, oddly enough, a decent one forensic-wise.  I mean, Brennan figured out sex based solely on the femoral head and age-at-death based on only a small part of the technique of assessing the pubic symphysis.  But at least it was based more in reality than the size of the C2 or other oddities they have used this season.
    • What did Angela get a hit on in the missing persons database?  There wasn't anything particularly identifying about the middle-aged male skeleton with developed upper arm muscles.
    • Osteophytes from fake breasts worn for a few hours once a week?  Nope.
  • Plot
    • Uh, so Sweets is a psychologist.  Not an FBI agent. Why exactly does he get his own murder investigation, other than plot contrivance?
    • Hodgins was pouring HCl from one giant beaker to another in mid-effing-air?  While not under a fume hood?  And was the HCl green for some reason?  Science!
    • (Why is everyone wearing sweaters in this episode and the upcoming one?  It's late spring in D.C.)
    • Wait, what's Booth testifying about to a congressional subcommittee?  I guess it'll tie into his getting shot next episode.
    • Is it just me, or did the writers do weird things with the pronouns for all the drag stars?
    • Can a non-traditionally-aged student be on a sports team in college?  I don't think you can with high-interest sports like basketball, although I guess technically Quentin would have preserved his eligibility by being in the military. Still, I can't imagine you can be on a college sports team at any old age.
  • Dialogue
    • "What does it mean 'to Brennan' someone?  Is that a compliment?"
    • Brennan: "You're finally using evidence to reach conclusions; I appreciate that." Sweets: "As opposed to my usual psycho-babble?" Brennan: "Exactly!"
    • "Anthropologically speaking, homosexuality is not a prerequisite for cross-dressing... it's an expression of personality."

Forensic Mystery - B. It wasn't at all telegraphed who did it. But maybe that was because they basically never mentioned the killer until he was the one who did it, for a reason that was only explained at the very end.

Forensic Solution - A-. Demerits for the hand-waving about IDing the victim through missing persons.

Drama - C-. I literally did not even catch the killer's name when he was first introduced.  I had to look it up at the end, and it took me several webpages to find out.  Lame.

May 14, 2014

Thanatourism in San Antonio, TX

I haven't done a "thanatourism" post in a couple years, but I just returned from giving a lecture on Roman health and diet in San Antonio, Texas, and wanted to post some pictures of my two-day journey, which was led primarily by AIA SW Texas Society treasurer, Joe Lamm, and president, Laura Childs.

Crockett in a Tub
San Antonio (the 7th largest city in the U.S., did you know that?) is famous for the Alamo, of course, and I learned that the word alamo in Spanish means cottonwood, a type of tree common to the area.  The story goes that the defenders of the Alamo, who included Davy Crockett and Jim Bowie, were killed and cremated by Santa Anna, the Mexican general and so-called Napoleon of the west, shortly after the battle in March 1836.  This account has been disputed, however, with some suggesting that Crockett surrendered or even that he lived.  Still, even if we buy that a bunch of Alamo defenders were killed and cremated, there is major discussion about where the remains were buried and whether remains found some time later were indeed those of Crockett, Bowie, and others.

I snapped this picture at the San Fernando Cathedral, the oldest cathedral in Texas.  The commemorative plaque claims that the remains of these men were excavated in 1938, on view for a year, and then entombed in the marble coffin that has become a kind of shrine.  I think it's more likely that whatever cremains still exist (if any) are a jumble of people from a variety of time periods. [Here's more from TAMU.] It's still a good story, of course, of local heroes martyred for defending their home.

Laura took me to the San Antonio Museum of Art (SAMA) to see the Greco-Roman collection, although we also peeked into most of the galleries.  SAMA's ancient collection has nice breadth, owing primarily to a wealthy collector who donated his massive collection to the museum.  So there are two Roman mummy portraits, red- and black-figure pottery, grave stele, marble statues of Roman emperors, etc.  I took a picture of the lead sarcophagus they have on display, which is probably from Tyre (Lebanon) and dates to about the 2nd-3rd centuries AD. I'm not familiar with lead sarcophagi from this area of the world and thought most of them were from areas like Roman Britain.  It's a nice piece, but there wasn't a whole lot of information on the card about it.  I also took a picture of these Roman marble boxes that held cremains. They are lovely, and their inscriptions have been translated for the information card.  But there is little additional context for them, or for the other funerary artifacts.

People often ask me why I got into Roman bioarchaeology, as Laura did when we were walking around SAMA.  I had originally wanted to do Greek bioarchaeology (which is another story entirely), but the underlying reason was the same: as a kid who voraciously read books on Greek and Roman archaeology and who stared at these kinds of funerary artifacts on display at museums, I really wanted to know where the actual dead people were.  These things are all well and good, and we can learn a lot about fashions and food and other aspects of daily life by looking at them, but I wanted to see the bones.  Now, since collectors have bought and sold Greco-Roman antiquities for centuries, it's not really surprising that cremation boxes and lead sarcophagi don't have people in them anymore nor that many of them have poor contextual information that can't be easily conveyed in a museum display or textbook.  But these sorts of objects are precisely what piqued my interest in the bioarchaeology of the ancient world.  SAMA is a lovely museum, but I wished there had been more contextual information and displays to really show off how various artifacts were used in daily life.

Finally, I don't usually buy myself souvenirs when I go on trips, preferring to get trinkets for the girls (or weirdly flavored salty snacks for my husband), but I couldn't resist this t-shirt I picked up in a gift shop in the San Antonio airport.  All in all, an excellent way to spend a couple days!

Thanks to the SW Texas AIA society for inviting me to come out and showing me around, and to the attendees at my talk, who made for a very lively question-and-answer session during which I learned a lot!

May 9, 2014

Lead Poisoning in Rome - The Geoarchaeological Evidence

In March, a new study came out in PNAS discussing "Lead in ancient Rome's city waters" (Delile et al. 2014).  It was quickly covered by major science news outlets, largely because of a mention of lead poisoning in Rome on the new Neil deGrasse Tyson-helmed Cosmos, with venues like TIME stating, "Lead didn't bring down ancient Rome," but others like Discover inaccurately commenting that "Lead in ancient Rome's water was 100 times natural level."  Now that I've gotten through the SAA conference and submitted final semester grades, I wanted to take a close look at the paper in advance of talking about lead poisoning in a talk I'm giving in San Antonio on Monday.

Lead pipe from Ostia Antica.
(photo credit: Chris 73 CC BY-SA 3.0)
The Delile et al. study is very well designed. The authors used sand and silt from a 9m-long core drilled into a channel between the Claudian and Trajanic basins at Portus Romae, the port city of Rome that lay about 25 km west on the Tyrrhenian Sea.  They also used soil from a 13m-long core drilled into what used to be a man-made branch of the Tiber River, now called the Canale Romano. Based on sedimentology, the authors were able to identify several time periods when the soil was accumulating. They tested several dozen samples from each of these soil cores, and they also took samples from five Roman fistulae (water pipes) dating to the 1st-2nd centuries AD.

This project involves Pb isotope values (not concentrations) to test whether the Pb present in the cores was naturally occurring or the result of anthropogenic (man-made) Pb use.  Pb isotopes, like Sr, O, and S, can actually be used to investigate mobility and migration of humans and animals.  We all ingest at least trace amounts of these elements because they occur normally and naturally in our environment.  Different ratios of these elements give us information, therefore, into the kind of environment in which a person grew up, allowing us to see if people or animals changed locations after they were born.  But testing the soil for Pb isotopes gave these researchers information into whether the soil's Pb was from the local environment or from imported Pb (and therefore anthropogenically-caused introduction of Pb).

Using the Pb isotopes, the authors found two major components when they tested the soil: first, there was naturally-occurring Pb likely from the Alban Hills (volcanic rock) and from Mediterranean seawater as a result of erosion of Apenninic limestone.  But second, there was a component that could not be explained using the local geology. Specifically, the Pb component they found is called Hercynian Pb, which is not found in the Italian peninsula.  It's normally found in SW Spain, parts of France, Germany, England, Greece, and the Alps. This anthropogenic or human-introduced Pb component is also, they say, consistent with four of the five fistulae they tested.

So what does this mean for the levels of Pb pollution in the Roman water system?  Here's where some of the news coverage gets some of the interpretations wrong.  Delile and colleagues (2014:4, emphasis mine) calculate that, given an estimate of Tiber River water running through fistulae at the height of the Roman Empire:
It can therefore be deduced that fistulae increased Pb in the water distributed in Rome over the natural level by a factor of about 40, 14, and 105 for the Early Empire, Late Empire, and High Middle Ages, respectively. [...] These levels are maximum values because they characterize the final output of the water system to the Tiber, while most Roman citizens would have used drinking water that was tapped, whether legally or illegally, all along the water distribution system. The inferred increases of Pb in the water of the Roman distribution system unquestionably attest to general lead pollution of Roman drinking water, but the Pb concentrations at issue are unlikely to have represented a major health risk.
Now, go back and read the Discover story if you're so inclined.  I'll wait.   Did you notice how the author cherry-picked the largest number, which represents the High Middle Ages (whereas "ancient Rome" generally means the Roman Empire when talking about lead poisoning)?  See how the author cherry-picks a quote about lead being a major public health issue, only to admit at the end that the authors of the study don't discuss health problems (except that they do in the sentence I've highlighted above)?  Lead is present in our environment, of course, and although 14 and 40 times sound scary, those numbers may not mean much if the natural level of lead is very low.  That's basic math.  Definitely the worst coverage of this article I've seen.

Getting back to the elegant study, though, the authors further show (Delile et al. 2014:5) using the chronology of the sediment cores and the fluctuating Pb isotope values that their data line up with written history:
The isotopic contrast between the fractions rapidly diminishes, although quite smoothly, from the Early to the Late Roman Imperial periods. This change is largely accounted for by the dramatically smaller contribution of anthropogenic Pb to leachates and therefore by a lesser pollution of Tiber water. One interpretation of this may be a redirection of spring water away from the lead pipes of Rome, in some way related to the controversial decline of the population or to a poorly documented deterioration of the water distribution system. 
The later fifth and sixth century transition is coevel with Belisarius' fixing of the decommissioned aqueducts of Rome at the end of the Gothic Wars (535-554 AD).  Byzantine repairs of the water distribution system may have remobilized massive amounts of corrosion products from abandoned lead pipes in which water may have stagnated for protracted lengths of time.  Although a causal relationship cannot be formally demonstrated, the discontinuities in the cores at Portus seem contemporaneous with historically documented events such as the struggle for the control of the port between Gothic and Byzantine forces (536-552 AD) and the damages inflicted to the water distribution system during the Arab sack of Rome in the mid-ninth century.
Really, really good stuff!

This paper, of course, makes me think of the Pb concentration (and isotope) data from my Romans buried at Casal Bertone and Castellaccio Europarco, just outside of Rome, in the 1st-3rd centuries.  Here's a chart of Pb concentration data from Britain and Rome, with data coming from Montgomery et al. 2010:

Lead concentration from skeletons from Britain and Rome.
(Raw data from Montgomery et al. 2010, Tables 11.2, 11.3, 11.4.)

If we could take the pre-Roman Britain lead level (0.08 median) as possibly analogous to pre-anthropogenic-Pb Rome, then you could have a 40-fold increase and not have widespread lead poisoning.  105 times (the possible level above natural Pb levels in the High Middle Ages for the Tiber basin), however, is pretty darned high.  Medieval Europe clearly liked their lead.

The most fascinating thing to come out of the Delile et al. paper for me is the idea that the Tiber was the source of the Pb pollution.  This isn't particularly surprising, since waste from the various industries within the urbs and the suburbium would flow into the Tiber.  And the Romans knew not to drink Tiber water or eat fish out of it; they were well aware of pollution, even if they didn't quite understand the mechanisms.  But these results give me pause because they could indicate that Romans whose skeletons held high levels of lead grew up playing and possibly drinking and eating close to the Tiber.  Since we have little information that links dead bodies buried in the suburbium with living quarters in the urbs, knowing that proximity to Tiber waters could result in high Pb values is a good bit of data to store away for when Sr/O analysis can give me a finer resolution for residence and mobility in the Empire.  That is, I hope that someday I can figure out where in Rome people lived by looking at their skeletons, historical information, geological data, and other contextual factors.  Skeletons are all well and good, but being able to understand living communities in Rome has always been my goal.

The Delile et al. article represents a massive step forward in helping all of us who research the ancient world understand more about the variation in environment and health in the Roman Empire.


Delile H, Blichert-Toft J, Goiran JP, Keay S, & Albar├Ęde F (2014). Lead in ancient Rome's city waters. Proceedings of the National Academy of Sciences of the United States of America, 111 (18), 6594-9. PMID: 24753588.

Killgrove K (2012). Lead poisoning in Rome - the skeletal evidence. Powered by Osteons. 

Montgomery J, Evans J,  Chenery S, Pashley V, & Killgrove K (2010). 'Gleaming, white, and deadly': using lead to track human exposure and geographic origins in the Roman period in Britain. Roman Diasporas, Journal of Roman Archaeology, Suppl 78, 199-226.

May 5, 2014

Who needs an osteologist? (Installment 14)

PBS needs an osteologist.  This isn't subtitled, unfortunately, so I'll transcribe it and you can click through at this link (it'll jump to the relevant spot after a skippable ad) to see for yourself.  Immediately before the picture you see below, the narrator says:
"... in particular, from this seventh cervical vertebra, part of the king's backbone."
Cervical, thoracic... same difference, right? (Credit: PBS.)
Here is the cervical spine, with C7 being the bottom-most:

Thanks to eagle-eyed PbO reader Rachelle Brydon for the link!

Previous installments of Who needs an osteologist?

May 2, 2014

Roman Bioarchaeology Carnival XL

This is a wee bit late owing to the massive, history-making flooding we had in Pensacola this week.  And it's a little short owing to the fact that today's the last day of the semester and I'm buried in grading.  So without further ado...


Credit: Photo courtesy Nicolas Morin (Discovery News)
Elsewhere in the Empire

  • 6 April. Ancient Egyptian mummy found with brain, no heart. (LiveScience)  During the Roman/Christian era in Egypt, some people were still being mummified after death, in the old style as it were.  The method of mummification of this woman seems to be anomalous, perhaps related to the fact that mummification was nearly out of style.
  • 18 April.  This piece on a site preservation grant from the AIA came through my news feed.  The award was given to a project called Adopting Narce, headed by Dr. Jacopo Tabolli. Narce (Italy) has numerous necropoleis dating to the 8th-3rd centuries BC.  This grant will help them preserve the site and do some public outreach too.

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