How human remains can inform forensics

Once evidence at the scene has been documented, the body undergoes examination to try to understand who this person was and what happened to them. This involves the work of forensic anthropologists, who use bones and other human remains to tell us more about the individual. Corinne Duhig, an osteoarcheologist at the University of Cambridge, explains to Julia Ravey what processes are undertaken to answer these questions...

Corinne - We start small scale and we are looking to build up a profile of that person, looking at their ethnicity, family relatedness sex, age, stature, and body form. And when we've done that, we've created in a sense, a little description of that person

Julia - And how does this play into forensics? So for example, how can we identify potentially how someone died from the remains that we find?

Corinne - As you can probably guess, it's very uncommon to find a clear cut answer just from the remains themselves. The smoking gun or the smoking bullet; the weapon embedded in the body or the cutoff head or whatever it is; is pretty rare. But what we can do is we can say things like -  I'm looking at this man's spine and he has one crushed vertebra that has not healed, so it's been done relatively recently. Now this looks a bit odd. What can you tell me about this man's story until the time when he disappears for us to work out; was this just an accident he had in the country where he'd moved to or was it something connected with his actual moment of death? So we start binding our information in with what the police have, the coroners have - absolutely combined work.

Tube Tannoy - The next station is South Kensignton. Exit for the museums and Royal Albert Hall...

Julia - Bones are a key component in informing identity. To see this evidence firsthand, I went to the Natural History Museum in London, which holds a selection of human bone replicas. Principle curator in anthropology, Heather Bonney, talked me through some of the characteristics bones can reveal.

Heather - This is a cast of a neonatal skeleton. And you can see that the bones are all really, really tiny. And then as the child ages, these bones begin to fuse and they obviously grow in size. And we can use either measurements of some of these long bones or the stages of the fusion to determine how old that individual was. And we can continue using development changes up until around the age of 30. Some of the very last bones fuse, fuse in your late twenties, but then we start looking at degenerative changes.

Julia - Well, I'm 29 now, I'm 30 in a few months. You're looking for degenerative changes.

Heather - Degenerative changes. And the issue with these are that they're far more impacted by your day-to-day life. This is a cast of a pelvic bone from a 65 year old male, who you can see the changes related to arthritis in the hip here. So what happens is that the cartilage within the joint erodes away and you essentially have bone rubbing on bone, which causes stress on that joint, and you can see the extra bone growth within there. It's not all nice and smooth, it's quite rough and nobbly.

Julia - Can we identify from remains potentially how they died?

Heather - Sure. So I've got some examples here.

Julia - Wow. That skull doesn't look too healthy.

Heather - No, this is the cast of a skull of someone who'd sustained quite a massive head injury during life that had completely penetrated the skull. But you can see how healed it is, it's all completely smooth and rounded at the edges. And the bone has grown over the hole that went through and they survived that. And they've lived for some time afterwards enough so that there's no reaction going on anymore. There's no bone gross happening. That's completely healed up. And then we have an example of a cast of a shotgun injury that did kill this individual. And you can see the very sharp edges and you've even got the outline of some of the shotgun pellets, where you've got these round circular depressions at the edges.

Julia - Whilst leaving the museum, one particular image of a human jaw bone caught my eye. And Heather explained the gruesome story it told.

Heather - This is a prehistoric individual who we suspect was decapitated. And you can see these cut marks here on the back of the mandible. If you're decapitating somebody from the back, you can't see where they're chin is and so it often leaves these cut marks.

Julia - It is a really blunt clear cut.

Heather - This took a few attempts here.

Julia - Oh my goodness. I feel like when you see something like that, you are almost transported back in time. I can like feel that in my jaw, when you said that took a few times and you can see the impact there on that individual.

Heather - Yeah, very much so it's pretty violent.