by Sue Black
The patella, which is named for the Latin word for a small, shallow dish or pan, is located in the tendon of the quadriceps femoris muscle on the front of the thigh, where it starts to form in the third year of life. Its purpose is to increase biomechanical efficiency of the knee. Its prominent position puts it at risk of fracture, usually from direct impact to the knee or as a result of falling on to the bone from a height. If the kneecap is shattered into too many pieces it can be removed, but these days surgeons are more likely to opt for reconstructive operations, generally involving wiring and tension-banding parts of the bone together. So forensic anthropologists are always on the look-out for bits of wire that might indicate orthopaedic intervention here.
As kneecaps are sensitive places with lots of nerve endings, they are a popular site for inflicting pain. Kneecapping is a deliberate injury meted out as a form of torture or punishment, usually by a bullet from a handgun and sometimes with an over-enthusiastic swing of a baseball bat or similar weapon. In fact, in many cases the impact misses the kneecap entirely, either by accident or design, and instead fractures the lower end of the femur or the upper end of the tibia or fibula.
Kneecapping was used in Italy in the 1970s and 1980s by the Brigate Rosse guerrilla group, and during the Troubles in Northern Ireland, by both Loyalist and Republican paramilitaries, as a punishment for a variety of transgressions. In the course of the conflict in Northern Ireland, around 2,500 cases are said to have been recorded. The ultimate punishment was the “six-pack”: a gunshot to each of the elbows, knees and ankles. More recently its use has been reported by the Islamic fundamentalist organization Hamas and by police in Bangladesh.
Accidental fractures of the tibia and the fibula are mostly seen in sports-related contact injuries or in collisions with moving vehicles, sometimes referred to as “bumper” fractures.
Fractures to the long bones of the limbs, and of the lower limbs in particular, need to be set in such a way that the length of both limbs remains more or less equal. If a patient is left with one shorter than the other, it sets up all manner of compensatory anatomical changes throughout the rest of the body. If your legs are of different lengths there will be effects on the pelvis and the vertebral column as well as on the limb itself. When we find evidence of a poorly set lower-limb fracture, we can say with some confidence that the person is likely to have walked with a limp, or at least an uneven gait, during their lifetime.
We will all have variations in the symmetry of our long bones and this can offer evidence of our “laterality”—the preference we show for one side of our body over the other. This is generally judged in everyday life by whether we naturally opt to write with our right hand or our left, but of course it relates also to which foot we choose to kick a ball, and to a predominance of one side over the other in general. And being a left-handed writer does not necessarily mean you will favour the left hand in every activity. For example, the right hand may be preferred when eating or playing a musical instrument or a sport. Plenty of cricketers bat or bowl with their non-writing hand.
However, about 90 per cent of humans are right-handed, and if your dominant side is the right, it is highly likely that your dominant foot will also be your right one. The degree of laterality varies between individuals, but it is highly unusual for someone to be truly ambidextrous, that is, to have exactly the same level of capability in both hands. Right-handedness seems to be supported by the intensity of motor and sensory cortex on the left side of the brain. Those who are right-limb dominant are therefore left-brain dominant for motor and sensory functions as the nerves are contralateral, crossing between their origin and their destination. Lateralization is not restricted to humans: it is widespread throughout the animal kingdom and has been identified in most primates, dogs, birds and rodents.
While right-handedness might have some genetic origin, it is likely that forcing small children to use the right hand, which was common practice in the past, and the fact that almost all the implements we use in everyday life are designed for right-handers, results in pressure to conform to right-side dominance.
Historically, the right side of the body was considered to be the “correct” one, and those who chose to write with their left hand were viewed as untrustworthy or even downright evil. This belief had its roots in the founding myths of many ancient cultures and religions and is reflected in the etymology of the words “right” and “left” in most languages. Right equates with proper, correct or straight; left with sinister, clumsy or weak.
There has been a considerable amount of scientific research on right- and left-handedness, including its genetic influences, indicators in the fetus and effects on birth weight, intelligence, income and many other matters besides. Results suggest that even at birth, there is evidence of dominance in the dimensions of the limb bones, with the right tending to be longer and more robust than the left. As an individual develops, dependence on one side causes a corresponding increase in muscle mass, and the difference in size between corresponding bones, right and left, increases.
The right humerus, for example, is frequently longer, wider and stronger than the left due to enhanced blood supply and muscle development. We can see this in our fingers: a ring will often be tighter on a right-hand finger than it is on the same finger of the left hand. In those who become left-side dominant, the bones on the right side of the body still tend to remain slightly longer, wider and more robust, but the difference between the two sides is reduced.
While we usually describe dominance in terms of our hands and feet, the real muscles of power that operate the upper and lower limbs are in the arm and thigh and the forearm and leg. So the differences in bone dimensions are more likely to be influenced by muscle mass in the long bones of the limbs than in the shorter bones of the hand or foot, where the tendons attach.
Although we can measure variations in the size of the long bones, it would be dangerous to claim that we can determine right- or left-handedness from bones alone, though that has not stopped some less than scrupulous anthropologists from doing so in the past. In the postmortem rooms of bygone days, we might have looked for callouses on the fingers as an indication of which might be the dominant writing hand but in today’s world of keyboards and keypads, those signs are rapidly becoming irrelevant or obsolete.
Of course, the odds are in our favour if we suggest that an individual is likely to have been right-handed. In practice it is recognizing the more unusual left-handers that is more valuable for identification purposes. But offering such opinions is risky.
When dealing with decomposing or disrupted remains, tracing the story of bones, of what has happened to them and when, can, as we have seen, be a challenge. Long bones are a terrific source of calcium for scavengers and the marrow in the cavities is appetizing and nutritious. As a result, they are very likely to be gnawed at when exposed to wildlife. We can sometimes suggest the type of animal that has been preying on them, whether it be small rodent or larger carnivore, by the marks left by their teeth on the surface of the bones.
But not all bodies will be predated, and sometimes the absence of carnivore activity can be as confusing for investigators as its presence, especially if they are not well versed in animal behaviour. To understand animal activity, you need to look at their life cycle holistically.
Foxes, for example, are not indiscriminate feeders. At certain times of year, they may totally ignore a large carcass such as a human body in favour of smaller, bite-sized meals that are more abundant, easier to manage and perhaps fresher, if they can make a kill.
They can be fussy eaters and human remains in the mid-liquefaction stage of decomposition are generally unpalatable to them. We might think that the more putrefied the remains become, the more attractive they will be to all predators, but this is simply not true. Foxes will happily feast on a relatively fresh body and crack into the bones to reach the calorie-rich marrow. And once decomposition has passed the mid-liquefaction point, they will return to gnaw at the
bones for the calcium benefits. But in between, they will often leave it alone unless food is in short supply.
One body, found on the edge of some farmland in the central belt of Scotland, showed surprisingly little indication of animal predation, given the proliferation of foxes in the area and its advanced stage of decomposition. The police speculated that perhaps the body had been stored elsewhere prior to being dumped at the edge of the field. But there was no evidence of foul play.
We knew that the attention of foxes would be influenced by when the body was deposited. Was it at a time of year when food was plentiful, or when there were no cubs to be fed? So when asked by the police to give our opinion, we were able to persuade them, backed up by the views of vulpine experts and gamekeepers, that, like other carcasses, human remains left out in the open do not always bear the signs of carnivore scavenging activities, and that the absence of these marks in this case did not necessarily point to the remains having been recently placed at the site.
The hands were missing, but this could be explained by the foxes’ food-storing habits. As they don’t know when they will next be able to eat, they conserve their food and will remove portable body parts such as hands first, for later consumption, and bury them elsewhere. This activity is called caching.
Missing body parts can often be tracked down by following the foxes’ trails and looking for disturbed ground. Foxes can be very protective of their larders and tend to “scatter cache” as a bit of an insurance policy rather than bury all their food in one place, where it will be at risk of discovery by other predators. But other animals do, of course, find and pilfer from the cache, with badgers being the main culprits.
The body was eventually identified as that of an elderly itinerant man. It was quite possible that he had crawled under the bushes to sleep for the night and simply died there. And the missing hands? They were subsequently recovered some distance away from the body, each buried in its own little cache. The bones showed the telltale puncture wounds of vulpine canine teeth.
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The skin and soft tissue covering the limbs, as well as the bones beneath, can aid with identification. The most common part of the body chosen for tattoos is the forearms in men and the shoulder or hip in women. As for the designs themselves, we like to think our inkings are unique but in reality most people go into a tattoo parlour and either pick one from a catalogue or ask the artist to copy something they’ve seen on someone else.
One young man, who wished to prove that he had what it took to become a member of a paramilitary organization, decided to make a video of himself dismantling and rebuilding a handgun to demonstrate his prowess with firearms. Adept as he may have been at stripping down and reconstructing a gun, he was evidently not the sharpest tool in the box in other respects, as he filmed the video in his own kitchen, which was a bit of a giveaway when the police became involved.
It seemed that he had at least watched enough forensic programmes on the TV to know that he shouldn’t let his face, or any distinctive clothing, be seen, or leave his fingerprints on any part of the firearm. So he wore nothing above the waist, shot the video from an angle where he was visible only from the neck down and donned a fetching pair of yellow washing-up gloves. But with the area between the top of his gloves and his shoulders bare, his film featured enough glimpses of the tattoos on his forearms for them to be identifiable.
I compared the tattoos in the video with those sported by the accused. The ever-popular “Madonna with a rose” on his left forearm could be seen above the top of his Marigolds. On his right forearm, his Celtic cross tattoo had been inked right next to a very prominent nevus (birthmark), and both the top of the cross and the birthmark were visible above the right glove. So we could match not only the tattoos to our bold hero but his birthmark, too, which led to him being detained at Her Majesty’s pleasure.
Many of us have a susceptibility to the formation of moles, freckles or liver spots, collectively known as punctate pigmentation. These are manifestations of areas of increased melanin, the pigment that gives our eyes, skin and hair their colour, found in the stratum basale layer of our skin. As melanin absorbs ultraviolet light, these areas darken in the sun. They also increase with age. Because these marks appear at random, they are specific to each individual, which makes them useful when comparing the anatomy of a suspect or victim with images captured on film of a person alleged to be the same suspect or victim.
Most of the cases we take on that require matching of anatomical features in photographs or videos relate to sexual abuse, frequently involving children. Two young girls accused a primary school caretaker, Peter Ryal, of sending them indecent messages by phone and touching them inappropriately. The police arrested him and obtained his phones and computer. Among the many images he possessed they found a short video taken on his mobile phone that showed another female asleep in bed. Her bra was raised and her exposed breast had been filmed.
The police investigated further and interviewed a teenage girl who was friendly with Ryal and his wife Gayle. She confirmed that she had stayed at the couple’s home, sleeping in the spare room, after having too much to drink one evening. She had been unaware of being filmed but said that the female in the video was her. Her face was not visible but she recognized her bra.
Gayle Ryal told the police that she was shocked by the images. However, when the case went to court, she changed her evidence and testified that she was the woman in the video filmed by her husband, claiming that they had been role-playing.
The court found itself at an impasse and the judge ordered a retrial, instructing the police, in the meantime, to seek an expert who could tell the difference between the anatomy of the teenage girl and that of Gayle Ryal.
They asked me to examine the video. It was of reasonable quality and, by breaking it down into individual stills, my team were able to map the pattern of moles across the shoulders and arms of the female subject. Then we did the same with photographs taken of both Gayle Ryal and the teenager and compared them with the map we had created from the material retrieved from the mobile phone.
The specific question put to us in this instance was clear-cut. We were not being asked to assess how likely it was that there was a match with either of the alleged subjects but, more straightforwardly, was the female in the video Gayle Ryal or was it the young girl? Gayle had a lot of freckles but no moles, and we could not match her to the photographic evidence. The teenager had moles (and no freckles), and in a formation perfectly replicated by those in the images. The answer to the question posed by the court was plain.
I was called to testify at the retrial. The judge became increasingly frustrated with Peter Ryal’s lawyer, whose only line of defence, it seemed, was to attempt to prove that I was not qualified to establish the difference between a freckle and a mole because I was not a dermatologist. Eventually the judge shut him down. The point was, of course, that for forensic purposes, it didn’t matter what you called it: it was a random pattern of punctate pigmentation that matched the skin of one individual and not the other.
After a short deliberation by the jury, Ryal was found guilty of sexual assault on a minor and making indecent images of a child. Whether or not Gayle Ryal was subsequently charged with perjury I do not know, but as for her husband, he was sentenced to eighteen months in prison and placed on the sex offenders register for ten years. In prison he was considered unsuitable for sex offender treatment because he continued to maintain his innocence.
I remember sitting in the witness room when the young victim came in with her family. She had already given evidence at one trial, and she was utterly distraught, shaking, crying and insisting that she just couldn’t go back into the courtroom again. It is hard for anyone, but especially someone so young, to have to relive their trauma in front of strangers, some of whom are intent on proving them to be a liar. It is no wonder that so many cases of rape or sexual assault are never reported or don’t reach the courtroom.
But in those t
hat do, forensic anthropology can help in many ways to bring the offenders to justice. I have often been asked if the work we do makes offenders more careful, and the answer is that it doesn’t seem to. I firmly believe there is no part of the human anatomy that cannot be of some value to the identification of the victim, the prosecution of the guilty or the exoneration of the innocent. Our work is not restricted to what we can read in the bones. And as techniques and technologies continue to advance, so the evidence our bodies become capable of revealing will increase.
9
The Hand
“We find only one tool, neither created nor invented, but perfect: the hand of man”
Julio Ramón Ribeyro
Writer, 1929–94
When I look at my hands, I see my father’s very large and capable shovels, not, unfortunately, my mother’s more delicate and feminine version. Probably best described as robust, they would never be chosen for a hand-cream commercial or to grace the front cover of Vogue. But they are mine, and they have done everything I have ever asked of them. They have dissected hundreds of human bodies, typed my thoughts, held my babies, wiped tears and bottoms and dug corpses out of a septic tank on a freezing cold day in January. Only now are these trusted and valued servants starting to complain, just with a twinge now and again.
The human hand is a miracle of evolution working in harmony with engineering. The American palaeontologist and biologist Stephen J. Gould was right when he admonished his fellow scientists for paying too much attention to changes in the human skull when analysing and presenting evidence for evolution. He believed they were looking in the wrong place: they should have been looking at the hands. Was it intelligence and big brains that allowed us to become such expert manipulators of our world, or was it when we stood up on two legs and freed our hands that we were finally able to challenge our brain to live up to its potential and keep pace with our dexterity?