[{"command":"openDialog","selector":"#drupal-modal","settings":null,"data":"\u003Cdiv id=\u0022republish_modal_form\u0022\u003E\u003Cform class=\u0022modal-form-example-modal-form ecl-form\u0022 data-drupal-selector=\u0022modal-form-example-modal-form\u0022 action=\u0022\/en\/article\/modal\/6229\u0022 method=\u0022post\u0022 id=\u0022modal-form-example-modal-form\u0022 accept-charset=\u0022UTF-8\u0022\u003E\u003Cp\u003EHorizon articles can be republished for free under the Creative Commons Attribution 4.0 International (CC BY 4.0) licence.\u003C\/p\u003E\n \u003Cp\u003EYou must give appropriate credit. We ask you to do this by:\u003Cbr \/\u003E\n 1) Using the original journalist\u0027s byline\u003Cbr \/\u003E\n 2) Linking back to our original story\u003Cbr \/\u003E\n 3) Using the following text in the footer: This article was originally published in \u003Ca href=\u0027#\u0027\u003EHorizon, the EU Research and Innovation magazine\u003C\/a\u003E\u003C\/p\u003E\n \u003Cp\u003ESee our full republication guidelines \u003Ca href=\u0027\/horizon-magazine\/republish-our-stories\u0027\u003Ehere\u003C\/a\u003E\u003C\/p\u003E\n \u003Cp\u003EHTML for this article, including the attribution and page view counter, is below:\u003C\/p\u003E\u003Cdiv class=\u0022js-form-item form-item js-form-type-textarea form-item-body-content js-form-item-body-content ecl-form-group ecl-form-group--text-area form-no-label ecl-u-mv-m\u0022\u003E\n \n\u003Cdiv\u003E\n \u003Ctextarea data-drupal-selector=\u0022edit-body-content\u0022 aria-describedby=\u0022edit-body-content--description\u0022 id=\u0022edit-body-content\u0022 name=\u0022body_content\u0022 rows=\u00225\u0022 cols=\u002260\u0022 class=\u0022form-textarea ecl-text-area\u0022\u003E\u003Ch2\u003ECrime fighting with microbes - how bacteria are helping figure out whodunnit\u003C\/h2\u003E\u003Cp\u003EFrom Sherlock Holmes to \u003Cem\u003ECSI: Miami\u003C\/em\u003E, crime scene investigators have long relied on scientific methods to turn routine observations into case-cracking evidence. Today, developments in the biomedical sciences could double the precision with which police estimate the time of death of victims, and help them follow the movements of suspects back in time.\u003C\/p\u003E\u003Cp\u003EA group of researchers across Europe is unravelling clues locked in one of nature\u2019s most ubiquitous location trackers: soil stains. \u2018Soil is all over the place,\u2019 said project coordinator, Professor Edouard Jurkevitch, at the Hebrew University of Jerusalem, Israel. \u2018You step on it, drive through it, carry particles of it on your clothes.\u2019\u003C\/p\u003E\u003Cp\u003EIf soil gathered from a suspect could be matched to its point of origin, the smallest stain might offer prosecutors insight into their past whereabouts.\u0026nbsp;\u003Cblockquote class=\u0022tw-text-center tw-text-blue tw-font-bold tw-text-2xl lg:tw-w-1\/2 tw-border-2 tw-border-blue tw-p-12 tw-my-8 lg:tw-m-12 lg:tw--ml-16 tw-float-left\u0022\u003E\n \u003Cspan class=\u0022tw-text-5xl tw-rotate-180\u0022\u003E\u201c\u003C\/span\u003E\n \u003Cp class=\u0022tw-font-serif tw-italic\u0022\u003E\u2018Each teaspoon of soil contains more bacteria than there are people on the planet,\u2019\u0026amp;nbsp;\u003C\/p\u003E\n \u003Cfooter\u003E\n \u003Ccite class=\u0022tw-not-italic tw-font-normal tw-text-sm tw-text-black\u0022\u003EProfessor Edouard Jurkevitch, Hebrew University of Jerusalem, Israel\u003C\/cite\u003E\n \u003C\/footer\u003E\n\u003C\/blockquote\u003E\n\u003C\/p\u003E\u003Cp\u003EAppraising the provenance of soil samples currently requires expensive case-by-case studies. Prof. Jurkevitch is working on an idea that could standardise the practice and make it compatible with equipment already available in forensic laboratories today. Rather than look at the minerals within each sample, he focuses on the life forms teeming between them.\u003C\/p\u003E\u003Cp\u003E\u2018Each teaspoon of soil contains more bacteria than there are people on the planet,\u2019 said Prof. Jurkevitch. Because different geographic regions foster distinct bacterial species, a census of microbes in a soil sample could, in principle, locate its place of orgin.\u003C\/p\u003E\u003Cp\u003EIn practice, however, it is impossible to manually sort through the thousands of bacterial species constituting each local population.\u003C\/p\u003E\u003Cp\u003EThe research project, known as MISAFE and funded by the EU, is working around this problem by using rapid genetic sequencing techniques. Tools for studying DNA have leapt forwards over the past decade and consortium partners are field-testing off-the-shelf kits capable of cataloguing the microorganisms present in a given environment.\u003C\/p\u003E\u003Cp\u003EInstead of sequencing entire genomes, the researchers save time by only sequencing one set gene in each of the microbes. This sequence provides enough of a unique identifier for each microbe to allow scientists to determine the ecological diversity of each soil sample.\u003C\/p\u003E\u003Cp\u003E\u003Cstrong\u003E25-metre range\u003C\/strong\u003E\u003C\/p\u003E\u003Cp\u003EDr Zohar Pasternak, a bioinformatician working in Prof. Jurkevitch\u0027s group, said that initial results identified significant differences in soils within a 25-metre precision range.\u003C\/p\u003E\u003Cp\u003E\u2018The technique cannot yet rule out coincidences when matching soil samples to crime scenes,\u2019 he said. \u2018But it can state with 99 % confidence that two soils do not come from the same place.\u2019 In this way, soil tracing is already providing supportive evidence to disprove false alibis in court.\u003C\/p\u003E\u003Cp\u003EHowever, soil is not the only sleuth provided by nature. Crime scene investigators also rely on partners in the animal kingdom to estimate the time of death of victims.\u003C\/p\u003E\u003Cp\u003E\u2018Within a day of most murders,\u2019 said forensic entomologist Dr Daniel Mart\u00edn-Vega, \u2018insects will have begun to lay eggs in the body of the deceased.\u2019 Police routinely estimate the minimum post-mortem interval of bodies by measuring the length of the maggots growing inside them.\u003C\/p\u003E\u003Cp\u003EOne limitation of the technique is that, for older crime scenes, the first generation of maggots may have turned into pupae, the intermediary development stage between a maggot and a fly.\u003C\/p\u003E\u003Cp\u003EThese pupae are surrounded by a hard, opaque shell and comparatively little is known about what is going on inside them. Opening them up to investigate the development stage of the fly interrupts the life-cycle experiment and, in the case of forensic studies, destroys irreplaceable crime scene evidence.\u003C\/p\u003E\u003Cp\u003EUnder a Marie Sk\u0142odowska-Curie fellowship, Dr Mart\u00edn-Vega\u0026nbsp;has joined the team of Dr Martin Hall at the Natural History Museum in London, UK. He is using a 3D imaging technique called microcomputed tomography to scan pupae with X-rays and record how much radiation is absorbed at each angle of measurement.\u003C\/p\u003E\u003Cp\u003E\u003Cfigure role=\u0022group\u0022 class=\u0022@alignleft-width100@\u0022\u003E\n\u003Cimg alt=\u0022Scans revealing details of the metamorphosis from maggot to fly help crime scene investigators date the crime scene. Credit: Dr Daniel Mart\u00edn-Vega\u0022 height=\u0022720\u0022 src=\u0022\/research-and-innovation\/sites\/default\/files\/hm\/MORPHIC_Presentation.jpg\u0022 title=\u0022Scans revealing details of the metamorphosis from maggot to fly help crime scene investigators date the crime scene. Credit: Dr Daniel Mart\u00edn-Vega\u0022 width=\u0022960\u0022\u003E\n\u003Cfigcaption class=\u0022tw-italic tw-mb-4\u0022\u003EScans revealing details of the metamorphosis from maggot to fly help crime scene investigators date the crime scene. Credit: Dr Daniel Mart\u00edn-Vega\u003C\/figcaption\u003E\n\u003C\/figure\u003E\n\u003C\/p\u003E\u003Cp\u003EA computer algorithm then works backwards from these results, like a Sudoku player, to reconstruct the density at each point in space inside the pupae shell, providing a 3D map of the developing fly and clues as to its age.\u003C\/p\u003E\u003Cp\u003E\u2018The technique is revealing how and when separate organs metamorphose,\u2019 said Dr Mart\u00edn-Vega. He is still investigating how external conditions, such as temperature, impact the development process in order to apply it to forensics. \u2018If the investigation method proves scientifically robust, it could double the precision of post-mortem interval estimates from pupae.\u2019\u003C\/p\u003E\u003Cp\u003EIn spite of these crime-fighting objectives and the occasional call for help from police investigators, Dr Mart\u00edn-Vega\u0026nbsp;describes his work as basic science. \u2018I am interested in the biology of these insects,\u2019 he said. \u2018My work is no different from that in any other scientific discipline.\u2019\u003C\/p\u003E\u003Cp\u003EProf. Jurkevitch agrees that the societal dimension does not affect how interesting he finds his research, but it does bear down on the burden of responsibility. \u2018Scientists have high standards for the integrity of the results that we publish,\u2019 he said. \u2018This is all the more important in forensics, as the methods that we are developing ultimately affect people\u2019s fates.\u2019\u003C\/p\u003E\u003C\/textarea\u003E\n\u003C\/div\u003E\n\n \u003Cdiv id=\u0022edit-body-content--description\u0022 class=\u0022ecl-help-block description\u0022\u003E\n Please copy the above code and embed it onto your website to republish.\n \u003C\/div\u003E\n \u003C\/div\u003E\n\u003Cinput autocomplete=\u0022off\u0022 data-drupal-selector=\u0022form-0cg6l-fnqotnwbbkkdvnv1oulelhdbzyukfxabqgovy\u0022 type=\u0022hidden\u0022 name=\u0022form_build_id\u0022 value=\u0022form-0CG6L-FNQotnwbBkKDVNV1OUlElhDbZYUkfXABqgovY\u0022 \/\u003E\n\u003Cinput data-drupal-selector=\u0022edit-modal-form-example-modal-form\u0022 type=\u0022hidden\u0022 name=\u0022form_id\u0022 value=\u0022modal_form_example_modal_form\u0022 \/\u003E\n\u003C\/form\u003E\n\u003C\/div\u003E","dialogOptions":{"width":"800","modal":true,"title":"Republish this content"}}]