(Press-News.org) EMBARGO: THIS CONTENT IS UNDER EMBARGO UNTIL 11 A.M. U.S. EASTERN STANDARD TIME ON FEBRUARY 12. INTERESTED MEDIA MAY RECIVE A PREVIEW COPY OF THE JOURNAL ARTICLE IN ADVANCE OF THAT DATE OR CONDUCT INTERVIEWS, BUT THE INFORMATION MAY NOT BE PUBLISHED, BROADCAST, OR POSTED ONLINE UNTIL AFTER THE RELEASE WINDOW.
For the first time, researchers have identified what appears to be a network of approximately 20 microbes that universally drive the decomposition of animal flesh. The findings have significant implications for the future of forensic science, including the potential to provide crime scene investigators with a more precise way to determine a body’s time of death.
“It’s really cool that there are these microbes that always show up to decompose animal remains,” said Colorado State University Associate Professor Jessica Metcalf, the senior author on the new work published this week in the journal Nature Microbiology. “Hopefully, we’re busting open this whole new area of ecological research.”
Decomposition of dead biological material is one of Earth’s most fundamental processes. Organic plant waste accounts for the vast majority of matter that is decomposed, a process that is relatively well understood. Comparatively little, however, is known about the ecology of vertebrate decomposition, including humans, and better understanding how humans decompose has the potential to advance forensic science.
This new study, a multi-year undertaking funded by the National Institute of Justice, involved decomposing 36 cadavers at three different forensic anthropological facilities — the University of Tennessee, Knoxville; Sam Houston State University; and Colorado Mesa University. The bodies were decomposed in different climates and during all four seasons. The research team then collected skin and soil samples during the first 21 days for each decomposing body.
Metcalf and her colleagues generated a significant amount of molecular and genomic information from the samples. They then used that information to construct an overall picture of the “microbial community,” or microbiome, present at each site. “Essentially,” Metcalf said, “what microbes are there, how did they get there, how does that change over time and what are they doing.”
Surprisingly, she said, regardless of climate or soil type, researchers found the same set of approximately 20 specialist decomposing microbes on all 36 bodies. What’s more, those microbes arrived like clockwork at certain points throughout the 21-day observation period, and insects played a key role in their arrival. “We see similar microbes arrive at similar times during decomposition, regardless of any number of outdoor variables you can think of,” Metcalf said.
A future in forensics
Identifying the decomposing microbiome’s consistent makeup and timing has important implications for forensic science.
Using machine learning techniques and data from the new study, as well as previous work, Metcalf and her collaborators — David Carter, professor of forensic sciences at Chaminade University of Honolulu, and Rob Knight, director of the Center for Microbiome Innovation at the University of California San Diego — built a tool that can accurately predict a body’s time since death, also known as the postmortem interval.
“When you’re talking about investigating death scenes, there are very few types of physical evidence you can guarantee will be present at every scene,” Carter said. “You never know if there will be fingerprints, or bloodstains or camera footage. But the microbes will always be there.”
What’s more, these microbes can be particularly useful, Carter said, under the types of conditions examined in the new study. “We’re talking about outdoor death scenes,” he said. “It can be difficult to gather information in those types of investigations.”
The director of the National Institute of Justice, Nancy La Vigne, views the research as particularly promising. “One of the principal questions of any death investigation is ‘when did this person die?’” La Vigne said. “This continuing line of NIJ-funded research is showing promising results for predicting time of death of human remains, aiding in identification of the decedent, determining potential suspects and confirmation or refutation of alibis.”
In addition to identifying the universal decomposers, the research team also attempted to determine where this microbial community came from. Notably, Metcalf said, they couldn’t find the microbes in soil microbiome databases or catalogs of human skin and gut microbiomes. They did, however, find the universal decomposers on insects. “It seems like the insects are bringing the microbes in,” Metcalf said.
Other research applications
These latest findings build on more than a decade of work by Metcalf, Carter and Knight, including an early study that involved decomposing mice on different soils in a controlled lab setting as well as a follow-up that involved decomposing four cadavers at the Sam Houston State facility. Zach Burcham, a former CSU postdoctoral student in Metcalf’s lab, helped lead the latest work.
“This research was a huge collaborative effort from a diverse team of highly knowledgeable scientists — a shining example of what can be accomplished when interdisciplinary teams join forces towards a common goal,” Burcham said. “This dataset is truly one of a kind, with broad-ranging impacts from microbial ecology to forensic science.”
In addition to the forensic applications, Metcalf sees other opportunities to put this new information to use. “I see a lot of potential applications across agriculture and food industries,” said Metcalf, who is in CSU’s Department of Animal Sciences.
Metcalf also intends to expand her research in this field, including potentially looking at the differences in the microbial ecology of small and large vertebrates. “I feel like we’re opening a whole lot of avenues in basic ecology and nutrient cycling,” Metcalf said.
Peer reviewed: Yes
Type of evidence: Observational study
UNDER STRICT EMBARGO
16.00 hours [UK GMT] Monday 12 February 2024 /
11.00 hours [US EST] Monday 12 February 2024
Risk of death 12% higher for non-White children in England
Twelve percent of infant deaths in England could be avoided if all infants in England had the same risk of death as White infants, a new University of Bristol-led study shows. Such a change, which equates to more than 200 deaths per year, would bring England – which currently has one ...
Have you ever wondered what happens in the brain when we move to the right or left? Most people don’t; they just do it without thinking about it. But this simple movement is actually controlled by a complex process.
In a new study, researchers have discovered the missing piece in the complex nerve-network needed for left-right turns. The discovery was made by a research team consisting of Assistant Professor Jared Cregg, Professor Ole Kiehn, and their colleagues from the Department of Neuroscience at the University of Copenhagen.
In 2020, Ole Kiehn, Jared Cregg and their colleagues identified the ‘brain’s steering wheel’ – a network ...
RIYADH, Saudi Arabia — February 12, 2024 — Hevolution Foundation, a global nonprofit organization that provides grants and early-stage investments to incentivize research and entrepreneurship in healthspan science, is announcing 49 new awards under its pioneering Hevolution Foundation - Geroscience Research Opportunities (HF-GRO) program.
As part of Hevolution’s mission to catalyze the healthspan scientific ecosystem and drive transformative breakthroughs in healthy aging, HF-GRO is funding promising pre-clinical research ...
A study led by the group of Didier Trono at EPFL has revealed a crucial survival tactic employed by cancer cells. The scientists have identified a group of proteins, known as “KRAB zinc finger proteins” (KZFPs), that help cancer cells maintain genetic stability and avoid immune system detection. The study is published in Cancer Research.
KZFPs are like managers inside our cells, helping to control which parts of our DNA are switched on or off. For example, some KZFPs interact with transposable elements, which ...
ATLANTA, Ga. - Dr. Christa Wright of Chemical Insights Research Institute (CIRI) of UL Research Institutes, will receive the Outstanding Technical Contribution in Industry Award at the 2024 Black Engineer of the Year Award (BEYA) STEM (science, technology, engineering and mathematics) Conference on Feb 17, 2024, in Baltimore, Md.
Dr. Wright is the Director of the Center for Toxicology and Human Health at CIRI. She earned a Ph.D. in Environmental Systems and Environmental Toxicology and a Masters in Cancer Biology from North Carolina A&T ...
LOS ANGELES (February 9, 2024)—Up to 5.8 million children and youth in the U.S. have experienced symptoms of COVID-19 that persisted long after initial infection. But diagnosing pediatric post acute sequelae of SARS-CoV-2 (PASC)—known as long COVID—in children remains challenging, as it can affect any organ system in the body, symptoms vary widely by individual, and little is known about its trajectory in patients over time. Children’s Hospital Los Angeles is one of 10 pediatric sites involved in the nationwide Researching COVID to Enhance Recovery (RECOVER) Initiative, sponsored by the National Institutes ...
The Cyber Readiness Institute (CRI) and Cybersecurity Manufacturing Innovation Institute (CyManII) at The University of Texas at San Antonio have launched a pilot program aimed at elevating cyber readiness and security within the energy manufacturing sector. This strategic initiative emphasizes CRI and CyManII’s shared commitment to strengthening their defenses against evolving cyber threats by providing essential support and resources for small and medium-sized manufacturers.
Through this partnership, CyManII will provide up to 200 U.S. manufacturers in the energy sector with access to CRI’s free Cyber Readiness Program. Focused on human behavior, the Cyber Readiness ...
Labeling cancer cells with genetic barcodes
“In ReSisTrace, we label cancer cells uniquely with genetic barcodes and allow them to divide once, so that we get two identical sister cells that share the same barcode. We then analyse single-cell gene expression from half of the cells before the treatment, while treating the other half with chemotherapy, or other anti-cancer treatment. From the surviving cells we can identify the barcodes of resistant cells. Using their sister cells analysed before the treatment, we can discover how the cells that ...
PULLMAN, Wash. – At a time when one viral video can damage a business, some companies are turning to their own commenting platforms rather than letting social media be the main outlet for customer feedback. Only one wrinkle: in this context, customers appear to prefer writing a message rather than leaving a video.
In a recent study, more participants indicated they would likely leave written compliments or complaints about service on a restaurant-provided tablet powered by artificial intelligence. ...
A study by a team at the Champalimaud Foundation (CF) has cast a new light on the superior colliculus (SC), a deep-seated brain structure often overshadowed by its more prominent cortical neighbour. Their discovery uncovers how the SC may play a pivotal role in how animals see the world in motion, and sheds light on the “continuity illusion”, an essential perceptual process integral to many of our daily activities, from driving vehicles to watching movies.
Imagine watching a film. The moving images you see are actually a series of static frames shown rapidly. This is the continuity illusion at work, where our brain perceives ...