Science Friday - Climate Risks, Power Grid Security, Necrobiome. March 23, 2018, Part 1

Episode Date: March 23, 2018

A report issued last week by the Department of Homeland Security said that throughout 2016 and 2017, Russian hackers had worked to gain access to control systems at unidentified power plants and were in a position to shut them down. Their actions have finally given Washington the political will to address vulnerabilities in the U.S. power grid. A new bill sponsored by Senator Angus King of Maine will establish a two year pilot program to develop techniques and technologies to better secure the grid. But it might just be too little, too late. After death, your microbiome continues on as the necrobiome—all of the bacteria, insects, fungi, and other organisms that are involved in decomposition. And the types of bacteria that show up on the scene follow a rather predictable pattern. Biologist Jessica Metcalf is studying this bacterial order to create a “microbial stopwatch” that could be used as a forensic tool, and joins Ira to tell him more. In the State of Science: Late last year, one of the world’s largest credit rating agencies announced that climate change would have an economic impact on the U.S. Moody’s suggested that climate risks could become credit risks for some U.S. states, including Alaska. And Popular Science editor Rachel Feltman tells Ira about the top science stories of the week in the News Round-up.   Subscribe to this podcast. Plus, to stay updated on all things science, sign up for Science Friday's newsletters.

This is Science Friday. I'm Ira Flato. We had some sad news from the conservation world this week. Sudan, the last male northern white rhino, died at the age of 45. His death leaves his subspecies teetering on extinction because there are only two females remaining, his daughter and granddaughter. But hope remains because, well, he'd explain why, is Rachel Feldman, Science Editor at Popular Science. Welcome back, Rachel. Thanks for having me.

Give me some hope, Rachel. Yeah, so the good news here is that researchers have already been working for several years, really, to prepare for Sudan's death. The thing is that neither of the two females are capable of carrying calves for various medical reasons, but they do have potentially viable eggs. Sudan was still producing viable sperm up until he died, and they were. collecting that pretty regularly. There's also sperm from several other deceased northern white rhino males. So the plan is to harvest eggs from Sudan's daughter and granddaughter, fertilize them, and then implant the embryos in southern white rhinos, which is the other white rhino subspecies, and they're actually about 20,000 of them. So they're quite abundant.

They're the only, they're arguably the most successful rhinoes, which is the other white rhino. especially in Africa. But they really want to bring back the north. He's a different rhino, right? Yeah. So, you know, subspecies sometimes can feel a little bit like splitting hairs. And if there are 20,000 white rhinos in total, why do we care that the northern is going extinct?

But the southern and northern rhinos have been separated for a really long time. One study estimated up to a million years. So they really are unique animals. You know, they live in very different parts. of Africa. And so most conservationists agree that if we can save the northern right, white, which by the way, is only teetering at the edge of extinction because of things we did, like poaching and habitat destruction. Most people agree that if we can do anything to save the northern white, we should. Yeah. Okay. Let's move on to something about the carbon footprint

of our food. Yeah. So most of us know that eating meat is not great for the environment. It produces a lot of greenhouse gas emissions. Also it takes a lot of water. It does. It does. Cows burp and fart a lot of methane. So just on the whole, not a great source of food from an environmental perspective. So a lot of people, you know, a lot of average Americans try to cut down on their animal product consumption, which is great.

But it hasn't really been clear, you know, what the distribution is in terms of how people are contributing to our carbon. footprint from diet. And this new study, which compared survey diet data with information about food emissions, found that 46% of our food emissions come from just around 20% of us. So they found that there's this group of a fifth of Americans that just eat so much more beef than average that they're producing eight times the emissions as the lowest percentage of people. And 72% of those emissions came directly from beef. Yeah, the difference between lowest and highest is almost entirely due to beef. So on the one hand, it's like a little disparaging for speaking personally,

somebody who eats like a slightly below average amount of animal products and is always trying to eat less because what we really need to do is get these super heavy meat eaters to eat an average diet. You know, it's even the country doesn't have to go vegan. We just need to get the people who are eating the most meat to eat like an average amount. Good luck on that. Yeah, we'll see. Let's also move on. To New Zealand, I understand, has some good news.

They've cleared a tiny, unpopulated island of invasive mice. Yes. It took $3.6 million in several years to kill 200,000 mice, which is very important because there are no native mammals in New Zealand. And this island in particular, the Antipodes, has a bunch of plants and animals that don't exist anywhere else in the world because of its total isolation. That isolation, by the way, meant that researchers had to actually climb up sea cliffs to get to the island. There's no harbor for a boat to bring them into. And then they lived there for several months. They deposited over 140,000 pounds of mouse poison.

And then they had to wait a couple years because even if a couple of mice had escaped the poison, they would have been able to totally repopulate the island. And they actually eat the chicks of these birds that don't exist anywhere else and have no natural predators there so they can just wreak total havoc. But it seems that they were successful. So now there are no mice left. My math is right. That comes to about six bucks a mile.

Yeah. Something like that. Pretty well worth their money. Finally, we're not doing a good thing, bad thing this week, but you have a story that fits that mold perfectly about the Trappist one exoplanet system, right? Yeah. Well, we're so used to hearing scientists talk about water on other planets as being such a cool thing. It's the baseline ingredient for life. So when we say a planet is potentially habitable, it better have water.

A really cool study this week showed that the planets in the Trappist system, which was in the news a lot last year, might have too much water for life, like way too much. You can have too much? We're talking about, so Earth has something like 0.02% of its mass made up by water, and we're a pretty wet planet as they go. these planets have maybe five to ten or even 50% of their mass taken up by water, and we don't even know what that looks like. We're talking about planets where everything down to the very closest bit you can get to the core is water. So physically we don't really understand totally how that would work. And also just the geology would be so different that at least based on our understanding of how life works,

There would be not enough of the molecules that are the building blocks of cells. So, of course, this comes back to the question of, like, how do we know that life on other planets is anything like ours? So maybe there is some kind of crazy life swimming around on these super weird wet trappist planets, but we certainly wouldn't be able to detect it based on what we know about life. Well, that's two hopeful stories. You brought to us this way. Yeah, you know, because you're right. How do we know?

We just assume that life is like ours, and that's how we have to look for it. Yep. Because those are the tools we have. You've got to work with the tools you have. Thank you, Rachel. Thank you. I'm Rachel Feldman Science Editor at Popular Science. Now, it's time to check in on the state of science.

This is KERNNO. St. Louis Public Radio News. Local science stories of national importance, and that's going to take us to Alaska. Let me tell you how that works. The credit rating agency Moody's recently announced that if states don't create what they say, sufficient adaptation and mitigation and mitigation strategies, it's legalese for, you know, how to tackle climate change, they could see their credit rating fall. It was a call to action from most states. You have Texas, Louisiana, and New York, but not to Alaska. Arguably, it's ground zero for climate change in the U.S.

Moody said, here's the reasoning, Alaska's credit rating is not a risk of being downgraded. even though Alaska is warming twice as fast as everywhere else in the country. Why not? Well, I'm not going to tell you. Here to tell you is Rasha McChesney, reporter for Alaska's Energy Desk. Welcome to Science Friday. Hello, Ira. Hi, how are you?

Pretty good. It's nice and warm here. We actually have some sun in Juneau for the first time in weeks. Wow. And that's all part of the story. So Moody's is basically telling states to get a plan for dealing with climate change or else the credit rating will fall, but not for Alaska. Why is that?

Well, the simple answer is that the impacts of climate change can be expensive. Think heat waves, hurricanes, flooding, you mentioned a few of those things. And as we've seen in recent years, it can cost hundreds of billions of dollars to recover from them. And these kinds of extreme weather events are projected to happen more often. And the expense of dealing with them is projected to climb as well. The strain on a state's budget would definitely impact its ability to pay its bills, and that's where the Moody's analysts were coming from. But the report largely ignored Alaska, and I asked our state's debt manager, Devin Mitchell,

why. He says it's all about the state's dependence on oil. Alaska is in this very unique situation where the effects of climate change are very, very obvious, but the impact on the state's credit is vague. In purely economic terms, none of the places in Alaska that are very obvious. are the most impacted by climate change right now, generate much revenue for the state's economy. Alaska is a one resource state.

Oil revenue is over half of the state's total budget, and it's about 90% of our discretionary spending. So unless something were to happen to the pipeline, climate change really just doesn't impact the state's ability to pay its bills, and that's where your credit rating comes from. It's Moody's. It's all about the money, not about the people or the melting tundra or any hat stuff. It's Devin, our state's credit manager, says it's an,

economic perspective. He's very, he very much stressed it wasn't a human perspective. That's quite interesting. But there is economic pressure to put on some of the cities, if not the state. Is that correct? Moody's, is pressuring the cities? So Moody's gives credit ratings to some cities too. And when you look at Alaska from the perspective of individual communities rather than the state as a whole, the story completely changes. in unalaska, which is actually the top fishing port in the country, it's this little town out in the Aleutian chain. A lot of that volume that makes them the top fishing port comes from Pollock that the fishermen bring in from the Bering Sea. And there's evidence that Pollock are sensitive to sea temperatures. The mayor there, Frank Kelty, tells me that their big concern is that if something happens to the fish,

their economy is just going to take a huge hit. And a lot of Alaska's coastal fishing communities would be, hugely impacted. There's millions of dollars that fishermen spend on fuel and groceries, and then there's jobs and property taxes for the cities from these massive fish processing facilities. The state has the most productive fishing industry in the country, and it generates about $6 billion in economic activity each year, just the commercial fishing industry. And so cities like Kodiak and Valdez in Analaska have gotten credit ratings in the past to finance things like big infrastructure projects.

On Alaska, they just had a $40 million port expansion. So it follows that those communities would feel that economic pressure to plan and adjust to climate impacts, even if the state as a whole doesn't. We get it. And that's because of that huge fishing economy, Moody's is interested. Thank you very much for taking time to be with us, Russia. Absolutely.

Thanks for having me. You're welcome. Rasha McChesney, reporter for Alaska's Energy Desk. When we come back after this short break, it's not if, but when? How do we stop the next cyber attack on the U.S. power grid? Stay with us. There are some proposals to actually go retro. Put a human-operated switch back in. Oh, wow, what an idea. We'll talk about it after the break. Stay with us. This is Science Friday. I'm Ira Flato. In late December 2015, a group of hackers carried out a cyber attack on Ukrainian electric utilities and cut off power to hundreds of thousands of people. What we didn't know back then was that that hacker group had connections to the Russian government

and that the attack in Ukraine was a dress rehearsal for what could happen here in the U.S. Because a reporter should last week by the Department of Homeland Security said that throughout 2016 and 2017, Russian hackers had worked to gain access to control systems at American power plants and were in a position to shut them down. The report comes as some Washington lawmakers have seen what happened in the Ukraine, and they are working, hopefully trying to make sure it doesn't happen here. I'm speaking in particular about a new bill sponsored by Senators Angus King of Maine and Jim Rish of Idaho, seeking to develop techniques and technologies to better secure the grid, allowing operators to literally punch controls manually and take the power plants off the Internet if necessary. Back to the future retro strategy. Others have suggested more futuristic approaches to securing the grid, from solar energy to microgrids,

and we're going to talk about all of them with my next guest. And if you want to get in on our conversation, our number is 844-8255-8-4-6-4-Sai Talk. You can also reach us at SciFri. Andy Greenberg is senior writer for Wired. He's here in our New York studios. Welcome to Science Friday. Glad to be here. And Joshua Pierce is Professor of Electrical and Computer Engineering at Mission.

technological institute. Welcome to Science Friday. Thank you. All right, so Andy, what happened in 2015? How did they do that? Well, this is a group that we now call Sandworm, and we believe that they are connected to the Russian government. They started with a kind of traditional fishing attack, and they used that to plant some... With a pH fishing. That's right. A spoofed email that planted malware on the kind of normal IT networks of three... electric utilities across Ukraine. And then that malware stole some credentials that the hackers then used, and this is the part that probably shouldn't have been possible, but there was a VPN on those utilities

networks that allowed them to remotely access not just the IT networks, but the operational networks. That other network that these utilities had that actually connected to the circuit breakers and switches and the things that allow you to turn the power on and off. deal with the electric load of an actual power grid. And from there, they used the actual help desk tools of these utilities to take control of the actual mouse movements of the operators so that these poor engineers were watching as they were locked out of their computers

and the mouse on their screen was hijacked and used to click through circuit breakers one by one to turn off power to hundreds of thousands of people. I couldn't do anything about it. Just sit there and watch the mouse do it. Helplessly. Helplessly. So let's jump back to 2016 and 17 here in the U.S. Did the hackers use the same thing here?

We don't know, to be honest. And we don't know if it's the same group. There are some indications that it's not, actually. So this actually first came to late six months ago when the security firm Symantec put out a report saying that a group they called Dragonfly 2, because it had some connections to another group called Dragonfly from a couple of years ago, had gained, similarly, had gained operational access to these American utilities, a handful of them. And the distinction is that means they didn't just put some malware on the IT network.

Like the Russians in 2015, they had gone that next step. They had crossed over into the operational network where they could have started to flip switches. And that's a scary thing. They were actually taking screenshots, and now the DHS has reconstructed. They've even published some of those screenshots that they took from the hackers of these control panels that included the the kinds of controls that you would use to start to cause a power outage. And so why didn't they take that mouse and do it on our systems also? Well, you know, there's the capability to cause a blackout, and then there's the question of would you actually do it if you could,

even if you're the Russian state, when would you want to cause a blackout? And it's not an easy answer at all. If they had caused the same kind of blackout in the U.S. that they did in Ukraine, And to be clear, the DHS, the news now is that the DHS has pinned that American intrusion on the Russian government. There would certainly be retaliation against Russia, a serious one. It might be seen as an act of war. Now, an active war in Ukraine kind of makes sense because Russia is at war with Ukraine right now, a physical war. So a bit of cyber war thrown in is not that it doesn't necessarily cause any sort of blowback for Russia.

that they can't handle. But the blowback for Russia, if they turn off the power here, would be immense. And they may have been aware of that. That doesn't mean that they won't. We think it might be. We don't know if it might be. Right. That's always a question, especially this administration. But that doesn't mean that Russia won't do this at some point in the future. If they want to send a message of some kind, if they feel like there is a kind of confrontation occurring with the U.S., if they want to, you know, I think most importantly, though, they want to, hold the capability over us so that. There's a little sword there. Something to be afraid of. Right.

Joshua, why is our grid built the way it is if it makes us so vulnerable to these types of attacks? Well, remember, it is like our greatest human achievement in service of technology that we are able to connect this enormously complex system and provide power to everybody, whether from your house, to the government, to the military bases. And it was set up actually to be resilient. Everything's connected. if you do have a power outage or if a particular plant goes down or a power line goes down,

the grid heals itself and you know everybody doesn't lose power. And it's only in these rare occurrences where we're either extremely unlucky, like maybe there's a couple weather-related disasters at the same time or orchestrated terrorist attack or cyber attack that you could actually have an enormous, large part of the grid go down. And so part of like what makes our grid so resilient is also what makes it so susceptible. with this type of attack, where if they do gain control to the SCADA systems, they could have massive blackouts and even possibly over a prolonged period of time.

Andy, you said that there were the two different systems working there, the operation and then sort of the overhead system. Well, there's sort of the IT business, the normal business network. They're sending an email on. Then there's the operational network that shouldn't be connected to the internet at all. So you're saying that should stay off the internet, the operational part? Absolutely, and that is the most fundamental protection for these systems is that they should not be connected to the Internet,

and then they won't be vulnerable to hackers. Unfortunately, it doesn't seem to ever be that simple. We in the U.S., in this recent incident, experienced an operational network penetration also. So that network was also connected to the Internet with the ability for these hackers to start flipping switches. We don't know why it was connected, but it seems that there's always a kind of need for engineers to update their software or connect remotely. And so they tend to create that connection and then hackers exploit it.

Joshua, do you agree we should separate the systems? Take one off. Absolutely, but we have to remember it only takes one infected USB stick stuck in the wrong port, and then the other side can get infected as well. And we've used similar techniques before ourselves so we know that it's certainly possible.

I mentioned there's been some discussion in Washington about whether we need a back-to-the-future approach to the grid infrastructure. I mentioned briefly that there's a bill called the Securing Energy Infrastructure Act currently making its way through the Senate. It's actually out of committee. It was proposed by Senator Angus King of Maine

and Senator Jim Rish of Idaho, sort of a bipartisan bill. And Senator King told us this week it was inspired by what researchers learned from the attacks in the Ukraine. The researchers found that it was old-fashioned, analog switches that had not yet been upgraded to digital equipment that enabled the Ukrainians to bring the grid back in a matter of hours rather than days.

And the bill that Senator Rish and I have introduced would instruct our national laboratories to work with several utilities on a voluntary basis to look for places in the digitized grid architecture where we can put in some old-fashioned analog switches that would require a human being to be there to touch the equipment in order to bring the grid down. Senator Rangis King of Maine. Andy, how did that strike you? Good idea? Well, I definitely, I don't know about going, you know, back to the past, going to

manual control, but I think we need to be able to fall back to manual control. And I think that what the senator maybe was getting at is that in Ukraine and 23, 15, when hackers used automation to turn off the grid, the response of the Ukrainian engineers was to get in trucks and physically drive out to all these substations and physically turn the power back on. That was the easiest way to recover. And as a result, you know, there was a power outage for hundreds of thousands of people, but it only lasted a few hours. Yeah. Joshua, what do you think? Would manual switches? Be good backup. It might be some backup, but I think we might be being a little bit naive, so it's just not a possible cyber attack. If you consider the 2013 sniper attack

in California and the PG&E substation, one person with one gun took out 17 transformers and cost $100 million of damage, and it took roughly 27 days to get it all fixed up. If there was ever a coordinated attack between both cyber and physical, it would be relatively easy to take out a large section of the U.S. graded and possibly for a very long time, because you know, it's not like these are transformers that you just pick up the shelf. Some of the lead times are very long. So it's the, there's, we are both vulnerable

to a cyber-based attack and a physical one without necessarily talking about major resources or extreme amounts of sophistication. Another point there, just to follow the professor's point, is that a cyber attack can be a physical attack. There have been demonstrations of hacker, digital attacks that destroy equipment. In 2007, the DHS actually demonstrated on video.

You can find this on YouTube, an attack called Aurora using this vulnerability that they found where they could physically destroy a generator using a digital attack. So if we imagine that hackers went the next step, and it does seem like the logical next step if you wanted to take down a grid for a long time, they could physically destroy equipment and not just disrupt it. Yeah, we know there are stories about the Israelis destroying centrifuges. with software and in Syria and you know I mean in Iranian nuclear efforts that's right Stuxnet this American Israeli yeah so you can just make as you say you can do physical destruction left let's go to the phone let's go to Al in Minneapolis hi Al good afternoon

quick question we had a similar conversation on the local public radio station here actually yesterday and it brought up something I was wondering about there's a lot of push right now for renewable energy and the one issue with renewable of course it's intermittent. So there has to be the throttling of the grid. And the discussion yesterday was a lot of talk of how things have to become much more automated and things like that, which is kind of ironically, they mentioned it makes a grid actually a little bit less secure. So I guess my question is, how can we build in the security and can we even proceed along the path of renewables, full throttle, you know, if we have to build in this type of a infrastructure to communicate

back and forth, this just appears to be allowing or opening the door for more possible vulnerabilities. Good point. Joshua Pierce? That is a great question. I can definitely answer it. And what we should be doing is what the Pentagon is doing. So the most secure we can make our grid is to create basically a federation of microgrids.

And so if you think about the U.S. military installations now that are dependent upon the civilian grid, which we know is extremely. extremely susceptible to everything we're talking about. One of the ways that they're hardening them is to create a microgrid at the actual base where they put in a large amount of solar. And so these microgrids have a large amount of solar energy, battery backup, and usually something else,

like a co-generator. And what that means is if the entire grid goes down, the microgrid islands itself and is completely functional and you can produce power for long periods of time. And so solar gives you that ability to produce power over long, periods of time for a large disruption, whereas most of the bases now only have generators that have fuel on site for a relatively short amount of time. And so if we want to have a secure grid

and go full throttle on renewable energy, what it means is we need to break up the grid into a bunch of microgrids that still act together as a full grid so that we still have all the benefits that we have today with our kind of giant centralized grid while still having the security. So if a hacker gets in and destroys one of the microgrids, you know, we only lose power for that particular facility or that town. We don't lose it for, you know, say the entire eastern seaborg. This is signed Friday from PRI, Public Radio International. Okay, so just joining us. So we're talking about grid hacking with Andy Greenberg of Wired and Joshua Pierce at Michigan Tech.

So you're basically saying, you know what nature knows is biodiversity works even in the power grid. grid system. And you want to make smaller little pieces that can survive, right? Right? Absolutely. And they all still work together, but they can all handle their, kind of their own problems. I think that the diversity of the U.S. power grid already is kind of a protection that these utilities are, you know, each have their own unique equipment to some degree. And I think that that has made it harder to cause a large outage. I think also, though, that that diversity makes it harder to protect them. That, you know, we do need to think on a utility level.

Each of these utilities needs to review its cybersecurity independently and make sure that power grid is, you know, a true disconnect. Let me get a quick calling from Jerry in Philadelphia. Hi, Jerry. Welcome, Science Friday. Hi, how are you? Hi, go ahead, quickly, please. Yes, I'm a security consultant, and I work in the regulatory area

and I'm familiar with NERCIP. I've seen Ted Cople speak at our sessions on security, and I believe that there is be required because there are several layers to get to the tags and the PLCs and then systems beyond that. And for instance, General Electric is moving toward a more superior cyber-protected PLC, and if it's on its own dedicated network such as a profanet or something like that, I believe that a lot of this is you really need to speak to the electrical industry and get a more even approach than what I'm hearing from the panelists. All right. Joshua, how do you react to that?

Certainly everything that the caller just said is useful and helpful. I think the problem at least that I've been looking at is not just considering one type of attack. So a couple years ago, there was a PhD thesis that found that with a handheld axe, striking seven places in the U.S. grid, you could cause a nationwide blackout. And as soon as that thesis was defended, it was classified and buried somewhere hopefully pretty deep. So we're, in some ways, I think we need to be careful about our sense of security, even if we have all hardened infrastructure. structure on the cyber side because it's not just cyber, it's also physical. And the major blackouts that we've seen so far have mostly been natural in cause. And it's just bad luck. It's like two bad things happening at the same time. And those do occur every once in a while. All right. We're going to have to leave it there and come back and talk more about this, really. Vital. A question, Andy Greenberg, senior writer for Wired and Joshua Pierce, professor of electrical

and Computer Engineering, Michigan Technological Institute. Thank you both for taking time to be with us today. We're going to take a break, and we're going to take a break, and we're going to talk about the necrobiom. Yes, we're going to talk about the bacteria and the bugs that take over after you die. We know you have a microbiome working nicely, hopefully, but after you die, there's the necrobium. We'll talk about it after the break.

Stay with us. This is Science Friday. I'm Ira Plato. This next story is not any old microbiome story. Yes, it's true. We talk a lot about our gut bacteria on this show. And yes, this is one of those discussions. But this is the microbiome in an entirely different realm.

We're talking about the bacteria and the organisms that live on after you're dead. It's called the necrobium, the ecosystem that takes over your body once you're deceased. My next guests are here to talk about the bacteria, the fungi, and other decomposers that are part of the necrobium. Also, how it might be used, the necrobium as a forensic tool to give clues about a person's death and maybe even how they lived. Jessica Metcalfe, assistant professor of animal science at Colorado State University. Welcome to Science Friday. Thank you so much for having me. You're very welcome.

Jennifer Peckle is an assistant professor of entomology at Michigan State University. to Science Friday. Hello, thank you for having me. You're welcome. Jessica, there are lots of bacteria in our body when we're alive. Where does the bacteria come from after we're dead? Is it the same gut microbes or do these bacteria only come after, come around for decomposition? That's a great question.

And it's actually one that was pretty hard to answer. So what we know from our research is that the bacteria that become abundant during decomposures, decomposition are basically in really low abundance in a lot of different places before death. So you can kind of think of them as they're sitting there waiting for something to die and release all these nutritious resources and pounce on it. And so some of the bacteria will come from inside your body. If you die on soil outdoors, for example, there are plenty of microbes that are in the soil that are also there waiting to respond.

And so it kind of depends on the context of your death. Can you actually predict the, is there a scale, a range, a sort of predictable way the bacteria arrive and then multiply and take over? Yeah, so kind of thinking about the big picture, obviously decompositions are really fundamental process on Earth, right? So we have lots of vertebrate organisms, and when they die, those resources are really valuable. And so over hundreds of millions of years, there's been this co-evolution of animals and microbes that have become really good at utilizing these resources.

So as a result of this, there is now this really predictable kind of like lockstep succession of organisms that take advantage of decomposing vertebrous. And so what that means. What happens is first? Who comes in first? so right so what's going to what's going to sort of bloom first or are the for example bacteria that are really good at utilizing resources quickly right and so they become really abundant and these are things like pseudomonas very opportunistic and then you have other microbes that's not all bacteria such as nematodes who then they really want to feast on all this bacterial biomass and so then they bloom and they become really abundant and so there's just There's thousands of different types of microorganisms that are taking advantage of different parts of this succession. Some of it's directly the resources that are becoming available from the cadaver. And then others, it's the food chain, right?

And so, you know, yeah, it's pretty fascinating. How far could you use these microbes to determine a time of death? You know, is it, can you days, months, years? Yeah, so let me put this in perspective. So when a person dies, often what happens if it's an unattended death scene, so where there's no witness, the medical examiner's office can use a number of tools within, say, the first 24 or 48 hours to estimate the last time of death. And there's also things like last text message. When was this person last scene? Where we're really focusing our research are kind of the less common unattended death scenes, but the ones that are harder to solve.

There's just not that many clues. And so our idea is to figure out what in the biology can we use. So one familiar concept that people might recognize is forensic entomology. So this is where scientists who study insects can use information about, say, the development of blowfly larvae to estimate that window of how long we think this person's been dead. And so my hypothesis was that, well, there's all this other biodiversity, most of its microscopy. we can't see it. But now we have the genetic tools to be able to quickly profile it.

And so what we found is that we've mostly focused on the first sort of three weeks post-mortem and that we can use this microbial succession over time to build this kind of stopwatch of microbial stopwatch, where if we have an unknown sample, we say, okay, here are all the organisms

that we profiled in it, where does it match on this stopwatch that we have developed based on, you know, experiments and what's our accuracy? Jennifer Peckle, I know that you're putting together something called the Human Postmortem Microbiome Database. That's correct. You need a good acronym for that, right? What information are you collecting? So this is a collaborative project that we have ongoing with various scientists around the U.S. and medical examiner. offices. And essentially what we're doing is expanding on the ideas that Jess has previously

talked about. We're really interested in how the community dynamics of the microbial organisms are occurring after death. So if an individual dies and you have a medical examiner office or an individual working there goes and swabs a body because that's how we collect most of our data is we swab different areas on the body. We process them using the genomic tools that are currently available. And what we're basically creating is a database to understand what bacteria are present when certain individuals die under specific circumstances, how these communities are changing after death. So if you're not discovered until maybe three or four days after you were last seen alive, your microbial profiles are going to be much different than if you were

discovered in the first couple of days after death. So we're interested in identifying which bacteria or microbes are present on the body when they're abundant on the body. And then also if the circumstances of death are altering what microbes are, or what microbes, excuse me, are present during the decomposition process. Do you include not just bacteria, but all sorts of the insects and other things in your profile? We do if insects are present. So I live in Michigan now, and it's cold most of the year, as many of you know. There is not a tremendous amount of insects that are available or present on bodies during most cases. So the microbes are a good alternative tool to identify in forensic applications if you don't have

insects that are present. Now, in warmer climates such as Texas, they actually have a full-time forensic entomologist on staff at one of the medical examiner's office there because there is, there are a lot of cases that do have insects present on the body after death. So what we're trying to do is use or develop biological signatures in the presence of insects and then also in the absence of insects that we can reliably use in forensic applications. 844-8255 is our number. 844-Sy Talk.

It can also tweet us at SciFri. You're not at any – I'll just throw this out to both of you. You're not at the point, though, where we're going to see this showing up on TV and CSI yet as a tool in forensics, or are we? Well, I think showing up on TV is different than it being actually implemented in a criminal investigation. But, yes, I think so. We'd probably see it.

You just press a button and boom, you have your time of death. And Jennifer can probably speak more to this because she has more of a forensic background. But, you know, there are certain hurdles that we have to overcome before you can use science in a court. case. And so we've been working towards some of those, some of those are peer review publication, trying to establish really good error rates and things like that. And Jennifer, some of these, the microbiome, the insects, do they go to a specific, they have a favorite part of your body to lunch on when they attack? So for the insects, when they arrive to a body, they really enjoy the areas that are going to be easily accessible for their larvae to develop on. So if you think about dark areas

that are present on the body. Think about your ears, your eyes, your nose, your mouth. These are also well-protected areas that could help prevent predation from occurring on the larval masses that occur. So they really like to go to those areas that also are not very dry. So this is, again, a area of the body

that the larvae can develop on and get the nutrition that they need, not desiccate, and be relatively well-protected. Does the soil change? And can you pick up signs of decomposition in the ground? Based on a couple of studies that I've been part of. And Jess, I'll let you follow up because you also have a tremendous amount of experience in this. But we've detected, at least in Texas, at a couple of the anthropological research facilities,

there are distinct microbial soil signatures present as decomposition is occurring. We have a limited population size, meaning the number of bodies that we've discovered these phenomena on. But it's been really consistent to identify these microbial signatures on human bodies as they decompose on soils. But Jess has done additional work on other organisms that she can talk about. Go for it. Yeah, we found that the soil is a great, it's a great sort of sample type for this clock. So we focus both on skin swabs but also the soil just right near the body. And you can see from like a forensic scientist, criminal investigator perspective,

not actually touching the body could be really useful. So being able to just swab the soil is an attractive option. And what we found is that it really works just as well as the skin. You see this clock-like change in the microbes in response to all these resources that are becoming available because of this decomposing, you know, vertebrate that's sitting on the soil. Could you tell that a body has been moved? It's died in one place and all that, you know, like we see on the crime shows all the time? So there's a couple ways that, and I think what you're sort of referring to,

you're kind of getting at like the heart of this is that the microbes contain a lot of information and they can give us clues in many different ways. And so, for example, one interest is if a body's buried, could you say have a transect along the soil, swab, you know, and then figure out where there's a signature of decomposition. Similarly, what we found, we did one experiment where this was with a mouse model, where we moved cadavers off the soil, and we found that even a couple weeks later, you could still detect that there had been a cadaver decomposing in that area. all those both microbial clues, as well as in some cases, we also look at the biogeochemistry of the soil.

So there's lots and lots of clues left behind that there had been something decomposing there. Similarly, if a body was placed there but hadn't decomposed there, you'd be missing that clue. You'd say, hmm, this is strange. There's no decomposers in the soil right now. There's something up. That's really interesting. This is Science Friday from PRI, Public Radio International, talking about, the necrobium. How did you get interested in this? You sound very, you know, excited by your work.

Yeah, so I did a, so my background was actually originally vertebrate genetics, and then I did a postdoctoral fellowship in ancient DNA. So I've studied sort of trying to get vertebrate DNA out of somewhat decomposed, say, bone or teeth. And then when we sort of have sort of had this microbiome revolution, you know, starting about a decade ago. I got really interested in the microbes associated with the vertebrates and with the host. And so, for example, one area of research that I've also worked on is trying to retrieve gut microbiome signatures from ancient material, such as ancient fecal samples. And so I got sort of into, so it's kind of by necessity, I had to start considering what is a decomposer microbiome look?

like? What are these microbes? Are they the same in every system? And so that's kind of how I got interested in sort of the microbial ecology of decomposition. And, you know, back in 2011, when I was a postdoc and Rob Knight's Lab, we sort of started having these conversations. I reached out to this great forensic microbiologist David Carter. And, you know, we had a phone call and was just like, oh, wow, there's all this stuff that we could do. Jennifer, you've been investigating ways that post-mortem microbiome could give clues to how certain demographics of people lived. Tell us about that. Right.

So what we're interested right now is basically we've performed a survey of over 200 individual death investigation cases in southeast Michigan. And we have different demographic populations that normally are not studied in the living microbiome. So individuals who have either different cultural lifestyles, who are from different geographic regions. So the data that we're gathering from the post-mortem microbiome includes a snapshot of individuals that typically are not involved in these living microbiome studies. And what we're detecting right now is that we have signatures that are very interesting about how the microbial communities consistently change after death.

So regardless of how an individual may have initially lived, we see very similar communities that change after. a couple of days of decomposition. So with the demographic groups, we're interested in expanding our populations and really identifying as to whether or not these signatures are going to be consistent based on the demographic groups. Gotcha.

Let's go to the phones. Matthew in Cleveland. Hi, Matthew. My question is that perhaps, say, insects are coming to laser larvae or eat the dead body, could they perhaps bring a different microbiome from a different dead body that they've already visited, perhaps change what the microbiome is inside the existing body? What a great question.

That is a fantastic question, and that's something that my colleagues and myself think about quite frequently. Blowflies are excellent mechanical vectors, so they can transfer the microbial communities from one resource to another, so you can think about when a fly lands on your potato salad. It's transferring bacteria from another resource that it pre-examination. landed on. Also, flies have this behavior when they land. They either regurgitate or deathicate. So that's a lot of material that can be transferred as well that a fly may have

picked up from a previous body. We are unsure at this point in time as to what the transfer rate will be from resource to resource, so body to body. But we do know that flies can definitely transfer these microbial communities based on where they're landing. So if you're at a picnic this summer and flies are all around, you may want to consider getting preventive mechanisms from allowing them to land on your food because you have no idea where they may have previously visited. It's what my mother said. Jessica Metcalfe, Assistant Professor of Animal Science at Colorado State and Jennifer Beckhol, Assistant Professor of Entomology of Michigan State. Thank you both for taking time to be with us today. One last thing before we go, please join me on April 9th at the Green Space here in New York to talk about one of my favorite subjects, The Orchid.

We've got a fantastic evening for you with special guest, Mark. Hachydurian of the New York Botanical Garden, Susan Orlean, author of The Orchid Thief, and there will be drinks and food, and you might even get to take home an orchid. So get your tickets at ScienceFriiday.com slash events, ScienceFriday.com slash events. One more thing, our thoughts and good wishes are with Christian Scott, our co-executive director, facing recent medical challenges this week. Get well soon, Scooter, and the bourbons on me.

That's about all the time. have for this hour. I'm Ira Flato in New York.