Nowadays, everything seems to have a forensic element: forensic psychology, forensic nursing, forensic pathology. So you may not be surprised to know that mycology is no different. What you may be surprised to know is that it’s a field of study that has been around since the 1950s and has helped to solve a large number of crimes around the world.
So, how can mushrooms help solve a crime?
Of course, one of the main ways that forensic mycology can help to solve a murder is when the mushroom is the cause of death. Cases that are often brought up are the case of an Indiana woman who murdered her husband with toxic mushrooms; and an Australian woman who murdered four of her ex-husband’s relatives by using toxic mushrooms in a Beef Wellington. Both cases are often brought up in the True Crime world, being featured on podcasts and YouTube Channels worldwide.
But what about when the cause of death has nothing to do with mushrooms?
Well, in murder cases, it’s common to find corpses hidden in clandestine places, either in urban or rural areas or even out in the wilderness. But how do you know if that is where said person died or if they were moved there after death? If they were moved after death, it points towards the death being a murder rather than a suicide (although it isn’t always the case!). How do you know how long the body has been there? Stages of decomposition can help, but it isn’t always a perfect science with a high number of variables that can affect it.
Putting people in places they claim not to have been
Mushrooms can link people and objects to places they claim they have not been. For example, in a shooting in Essex in the UK, spores from a specific fungus – Pestalotiopsis funerea – that infected trees from a certain area were found on the back of a suspect from where he had leaned up against the trunk. Whereas these could have been acquired elsewhere, this evidence was used alongside others to provide a full picture of what happened that day. In another case, where the body of a woman was found in a patch of stinging nettles, two fungi that were commonly found on dead stinging nettles – Periconia sp. and Torula herbarum – were found both on and under the body and in the suspect’s car.
As each species of fungi have a specific environment where they grow and thrive, by analyzing each species of fungi on an object or person can narrow down where that person has been. This is compounded by the presence of rare fungi which have been introduced into environments by humans.
Telling how long someone has been dead
Many fungi can be found in decomposing tissues, including some that cannot be found in any living tissue. This can, therefore, be used to estimate the time of death by observing the age of certain fungi species on a body. If that species can only grow on dead tissue, then it stands to reason that the corpse cannot have been alive any time shorter than it took for those fungi to grow.
The first case where such a technique was used was in the murder of a Belgian Baroness. The body had been kept at a constant temperature in her bedroom, and experts used the growth of a group of fungi – notably Cladosporium sp., Fusarium sp., Geotrichum candidum, Hormodendron sp., Mortierella sp., and Penicillium hypogeum – to estimate that the body must have been dead for eighteen days. This was later confirmed when the murderer confessed, and the use of such techniques has been solidified in forensic mycology ever since.
In another case, where fungi proved vital in finding the correct time scale, a medical examiner had predicted that the body had been in situ for less than 48 hours. However, by studying the growth of fungi on and around the body, forensic botanists (who oftentimes also have expertise on fungi) predicted that it would have been in place for between three and five weeks. It was later discovered that the body had, in fact, been there for four weeks and three days.
Finding how long something, or someone, has been in the same place
Sometimes the method of detecting the length of time a body has lain in a particular place is due to the unique nature of specific species of fungi. For example, scientists were able to find how long a plastic-wrapped body that was laid on top of a colony of Xanthoria parietina, otherwise known as Yellow Scales, had been in situ. Xanthoria parietina, when grown in plenty of light, is a bright yellow-orange (which lends to its name!). However, when growing naturally in shade, the lichen grows as a gray color. However, the lichen will turn green if it is moved to a too dark and moist environment. This happens over a known period of time, and as the lichen found under the body had not yet turned green, it could be determined that the body had been moved to the area less than 5 days before.
More non-traditional uses for mushrooms
Are you interested in other nontraditional ways that mushrooms are being used? Check out our other guides on how fungi are being used to clean up oil spills and monitor environmental changes.
