It’s that time of the year again where we start to think about holidays and annual leave. Maybe you fancy a little city break, or a spot of camping (although God knows why, it’s the worst). Maybe you fancy a trip to the beach, kicking back in the sand and letting the warm waves wash over your feet. If you do, you’re a fool. The only people who can relax at the beach are those who haven’t seen Jaws. Or Jaws 2. Or Jaws 3D. Or Jaws: The Revenge. Or The Shallows. The Meg. Sharktopus. Mega Shark vs Crocosaurus. Mega Shark vs Giant Octopus. 2-Headed Shark Attack. 6-Headed Shark Attack. Sand Sharks. Bermuda Tentacles. Or indeed the recent trailer for The Meg 2: The Trench. Yet despite this extensive and compelling body of work, the volume of research that has been undertaken on what happens to bodies in the sea and the implications for forensic investigation is surprisingly small.
But this is changing. Recently a new article in The Conversation highlighted the specific challenges that are faced when a crime scene is underwater noting the importance of multidisciplinary teamwork, the use of water-based organisms (like diatoms) and adapting existing methodologies. This has been followed up by a paper in Forensic Science International: Synergy which optimised visual recording for underwater contexts. I would like to add here that the lead author, Rossella Paba (who I have known and worked with for years) once tried to get me to start diving with the argument that I’d see sharks. Which was a bold, and entirely misjudged, gambit.
Although I had nothing to do with the content of this excellent article, I did bring two of the trio of authors together in a sort of “Oh! You need to talk to Paula/Rossella” sort of way. But this is an area that I have some history in. Back in the day (the early noughties), when I was up in Dundee, we had some case work come in. A vertebra had been found on the beach, and the police wanted to know where it came from and who it belonged to. Turns out, we could answer neither. The latter because it was a single vertebra and beyond saying it was from an adult human, there was little else to say. But the former was more interesting. We couldn’t say whether the bone had washed up on the shore, had flowed down the adjacent river, or been exposed as the sands were eroded away. This seemed like a really simple question, and yet it had stumped us. And as is ever the way, our casework led to a new research question.
Frequent readers of these posts will know that I have a sister who lives down in Southampton and does stuff with sand and mud. Something to do with being Director of the Channel Coastal Observatory. I don’t know, I don’t really listen. Anyway, we had been talking for a while about doing some research together, and all of a sudden we had the perfect project. Could we look at the damage to bone caused by sediment to infer whether a bone had been washed down a river or had come from the sea? It was a fantastic project, where we did a preliminary study and then followed it up with a PhD project (you can read one of the key outputs here). Perhaps most rewardingly, it finally gave my sister’s career some meaning. The results were positive – you can indeed detect river flow on bone from abrasions left by the sediment. But that just gave us more questions – like, could the abrasions be mistaken for natural pores in the bone? Well, one MRes project (and paper) later and we could confidently say ‘probably not’.
In 2015, James T. Pokines and Nicholas Higgs published their review of cases recovered from the shoreline around Massachusetts noting the general macroscopic alterations resulting from submersion. But that paper came out a year before our last one. We then have a bit of a gap. 2021 brings us a couple of papers looking at post-mortem submersion interval (PSMI) estimation using the microbiome – one from a freshwater lake and one from a freshwater river. Despite being very similar studies, they did demonstrate that microbial communities could be used to estimate PMSI. Which is neat. A later study undertook a review of PMSI from the perspective of bony change, and detailed a suite of techniques that can be used. And if you like sponges, you’re in luck. In 2023, Guareschi et al analysed patterns of bioerosion from marine sponges to add to our understanding of aquatic taphonomic/diagenetic pathways. This year also gave us a paper on the effects of fluvial transport in water on saw mark evidence (they’re mild, in case you were wondering). In the burned bone literature, this marks almost a second wave of research which starts to explore the impact of the taphonomic factor not on bone generally, but on anthropological methods.
More recent publications have started to focus on large-scale aquatic casework. For example, there’s a 2022 paper from Italian colleagues examining the impact of submersion on genetic analysis specifically in relation to the tragedies occurring to migrants crossing the Mediterranean Sea.
And we can bring this right back to where we started – with the examination of bones on beaches. This year, an excellent paper by Maria Ktori came out discussing the strategies used by the Committee on Missing Persons in Cyprus to exhume remains from coastal regions. It’s well worth a read, not just for the science but also the wider context. There’s still much more work to be done in this area, but at least we are starting to see an increasing interest in this particularly challenging context of forensic work.
Footnotes:
- Given that I have just discovered the existence of the octopus settlements, Octopolis and Octlantis, I think you should too. Discovered as in just read about them, not discovered as in stumbled across them while swimming.
- I would very much recommend the book Kraken: The curious, exciting and slightly disturbing science of squid.
- Here’s why you don’t use the word Octopi…