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Posts Tagged forensic anthropology

On vein patterns and dead pythons – outdoor body recovery course Anna Sandiford Jul 10

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The Outdoor Body Recovery Course was fun.  It’s a difficult thing to say to people because how can it be fun collecting samples from unfortunate individuals who have died and whose remains are found outdoors?  It’s one of those uncomfortable  definitions of ‘fun’ that would probably be more appropriately labelled ‘rewarding’ or ‘fulfilling’.  However, on this occasion it was fun because there was no real corpse and the idea behind the course is to educate police officers, crime scene examiners and other crime scene attendees on how to collect samples from any crime scene found outdoors (including vehicles).

It was fun because the weather was great, the attendees were interesting, interested and motivated and I left the course feeling that I had really added something to their arsenal of tools for investigating crimes. As I indicated last week though, the course was not without its problems when our training grave was robbed.

I always think that a good course is one where not only have you taught someone something but you also come away with more knowledge than you had at the start. This is a selection of bite-sized knowledge nuggets that I learnt:

  • Burying a human ornamental skull with your dead pet python in the woods can cause unnecessary police hassle when the skull is exposed through loss of top soil and freaks out passers-by who call in a full police excavation team.
  • When only a torso is recovered, examination of the lymph nodes can help determine if the deceased had tattoos because the ink collects in the nodes.
  • There is a vast database of penis vein patterns – these can be used for including or excluding men who choose not to show their faces but rather their genitalia in pornographic and abuse videos.
  • Vein pattern analysis in other body areas can be used in the same way – facial features are not the only way to identify a person in video footage and photographs.
  • Archaeologists really should be the people excavating graves – without them there is a real risk of loss of stratigraphic information (i.e. the order in which events occurred), which can help with, amongst other things, determining the age of the grave. There are apparently several classic examples where archaeologists were not fully involved including the Yorkshire Moors searches and digging up the patio of serial killer Fred West’s house in Cromwell Street.
  • Freshly boiled water is how to properly preserve a maggot; if the water’s not hot enough then the maggot is preserved in a curled fashion, rather than straight which is what is required for proper examination.
  • Birds’ nests really can contain hair and fibres – I found one on the ground near my body recovery site. A valuable if rare source of trace material when trying to locate human remains in difficult terrain.

Bones: animal or human? Anna Sandiford Apr 11

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Although this isn’t really my area, some of my colleagues work with interesting ‘things’ that are found at crime scenes or what turn out to be crime scenes, namely bones.

A huge amount of police time can be taken up in tackling the problems of ‘stray’ bones found by members of the public or unearthed during building works.  The first question is usually, ‘are they animal or human?’  While this is being resolved, the scene needs to be made secure, someone deployed to sort it out and all the paperwork completed.  The best (and fastest) way forward is to photograph any bones with a scale and email the image to someone who knows: a forensic anthropologist such as Professor Sue Black and the team at bones@dundee.ac.uk where they provide a 7-day service with a rapid turnaround time — and an answer!  To-date, the fact that some 90% of the images they have received have been animal shows how much police time has already been saved.   Perhaps our very own Dirt Digger can help with New Zealand finds?!

For best results, all photos should be taken on a clear background with a legible scale. These photos show examples of:

what not to do….

what should be done….

One of the most frustrating problems that can arise is the casual discovery of bone, often handed in by dog walkers, gardeners or building contractors. Once the bone is identified as human the question is ‘how old is it?’ Human remains can often be seen to occupy specific places in the ground or on building sites and an archaeologist can usually give a reasonable answer as to whether the remains are of ‘forensic interest’.

However, when there is no obvious buried or concealed context the problem becomes much harder.  Sometimes, bones can be traced back to a source such as a scavenged burial and the archaeologist can be brought in again but, if not, what’s the next step?  Visual examination of whether or not the bone(s) ‘look’ old or not is unreliable and usually inaccurate and most of the scientific techniques available are unlikely to be very helpful in establishing forensic relevance.

Radiocarbon dating is one of the better ways forward, not because it can necessarily produce a precise date, but because it can sometimes determine whether the body predates or postdates the 1950s.  The reason for this is the so-called ‘bomb effect’, caused by the atomic bomb detonations, which significantly affected atmospheric radiation at that time and can be detected in organic material that incorporated the radioactive material.  Because this peak of radiation tailed off, it may be possible to calculate where on the ‘tail’ the sample sits, thus helping to give it a more accurate date (allowing, of course, for analytical error, sample type, etc.).

Radiocarbon dating is a complex process and there is a limited number of laboratories offering this service; New Zealand is, of course, the proud owner of a cutting-edge instrument.

If the bones prove to be within forensic timescales there may be dermestids present (a type of skin beetle most commonly encountered by humans as pests in stored products and carpets, although several species will also consume decaying carrion). They are therefore found with regularity by the forensic entomologist (such as Dr John Manlove at MFL in Oxford) in larger numbers where bodies have been decaying for longer as they have a distinct preference for drier feeding material.  Dermestids will feed on the fibrous tissue which remains after the bulk of the biomass of a carcass has been consumed by other insects.  They will clean all of the tissue from bones leaving only the skeleton remaining.

Dermestids can be introduced artificially in the laboratory to clean soft tissue from bones.  This has the advantage of resolving fine damage in situations where a more aggressive technique may cause damage to the bone itself. The process is a natural one which, for example, will clean the tissue from human vertebrae within a few days.  MFL has one of the two breeding colonies of dermestids in the UK (now that would be one of those ’more interesting work stories’ and it definitely sounds like something you’d see on Bones…).

All in all, discovery of a single bone can lead down roads to all sorts of interesting endings….

[written with great assistance from Dr John Manlove]

Finding new 9/11 victims Anna Sandiford Apr 22

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Forensic anthropologists and archaeologists have been sifting through 611 cubic metres (21,600 cubic feet) of material from the World Trade Centre bombings and have found twenty potential remains from humans. This is not, of course, the same as saying the remains of twenty people have been found. These remains were not discovered at the actual site of the WTC towers but at the unfortunately named Fresh Kills Landfill. I really think they should have changed the name a looong time ago. The location was used to sort through rubble from the attack sites and the current investigation is planned to last three months.

Many of the victims of the disaster were, unfortunately, vapourised or crushed beyond recognition, which is why DNA scrapings were taken from the surfaces of buildings that survived the blasts but still many hundreds of people remain “missing”, i.e. no evidence of them has been identified.  Bone fragments were still being found around the site in 2007, six years after the initial event.

As I’ve said before, this kind of work is not pretty, it’s something that people forget has to be done and it’s done by people who don’t often receive any recognition for it, they just do it. “Unsung heroes” is corny and maybe it’s not directly applicable because it’s not dangerous work in the sense that they’re not present at the time of physical danger but forensic specialists like these can help bring an end to the event for the families of those who are still missing – and that has to make it all worthwhile.

For people considering a career in forensic anthropology and archaeology, these are exactly the sorts of situations where your skills would be applied. Perhaps not on something so high profile, but victims of mass disaster or even murder are everywhere and they all have a story to tell. It’s about finding them and then telling the story for them. Fascinating, but draining work.

Excellent book: Death’s Acre — Beyond the Body Farm Anna Sandiford Nov 19

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What happens to the human body after it dies? Well, after the TV program two nights ago about what happens to bodies when they are gifted to research, it’s been possible to get a visual insight into the ‘after life’. If your stomach’s not up to it or you can’t stand the smell, “Death’s Acre, Beyond the Legendary Body Farm” by Bill Bass & Jon Jefferson is an excellent read. It’s largely autobiographical in that it’s written by the man who founded the Body Farm (to whom and to which I have referred in an earlier post) and it’s an extremely insight book into the world of forensic anthropology.
Dr Bill Bass established the Body Farm in 1980 – it’s now a major research facility dealing with how the human body decomposes under different circumstances after death (locked in the boot of a car in hot weather or cold weather; how long bodies stay submerged in water; what happens if a body lies on a coin for twelve days…the possibilities are endless because the circumstances of casework are endless) – it’s the only facility of it’s kind in the world – probably because no-one else wants rotting corpses lying around in the open air. Fascinating reading and not gory at all (well, not my most forensic science book standards….).
He provides interesting case examples and hasn’t been afraid to admit where his knowledge was lacking in the early days and why, therefore, considerable research was required to bring the subject to the high level it now enjoys.
Dr Bass writes in a clear and enjoyable way – he’s one of those writers who can convey a difficult and somewhat morbid day job into a fascinating learning experience for the reader. I love reading books like this because I always come away having learnt something new – and doing that without having to read a dry text book is a plus as far as I’m concerned. Plus his story about being told off by his wife for boiling up bodies on the kitchen stove makes me feel less guilty about wrecking expensive household items during a recent research project…

The Body Farm Anna Sandiford Nov 02

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After having spoken with some friends and colleagues recently, it became apparent that the field of forensic anthropology was not well known. This surprised me because I assumed that everyone had heard of the Body Farm – not just the book by Patricia Cornwell, but the place for which the book was named.

For those who don’t know or who are interested in a career in forensic anthropology or other related fields (forensic entomology and such like) the Body Farm is the informal name for the Anthropological Research Facility at the Forensic Anthropology Centre, Department of Anthropology, University of Tennessee, USA. It was founded by William Bass in 1980 in order to answer some of the many questions about how the human body decomposes in different environmental conditions after death.

At that time, even very basic questions about forensic anthropology had not been answered, so Dr Bass started by just lying a corpse out on the ground and, with the help of students, observed and recorded what happened to the corpse over time.  It takes a very special sort of person to handle this kind of research….

Over the years, the Body Farm has answered many basic questions, such as how a body decomposes in the boot of a car in mid summer – which they tested by putting a body in the boot of a car and watching what happened. Or how a body decomposes when submerged in water or at what stage after death bodies float in water (apparently, some float like a cork from the get-go, others sink like a stone).  They also buried bodies and then exhumed them to see what happened, and also set fire to them.  They did have problems at the start with people not realising that real human cadavers were strewn about an area of (fenced) wasteland to rot at their leisure but it seems that things have sorted themselves out now.  The research facility receives quite a lot of donated bodies (a kind of full menu of organ donation), which is the ultimate recycling program as far as I can see.

The answers to the questions that the Body Farm has answered seem to be something we all assume have always been known, but the research coming out of the Body Farm is constantly answering new questions that arise in case work. As I always say, no two cases are ever the same, no matter how similar they appear.  If you’re interested in reading more about it, I recommend Death’s Acre: Inside the Legendary ‘Body Farm’ by Bill Bass and Jon Jefferson, 2003.  Fascinating – and, for those of a more sensitive disposition, hardly any gore at all.

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