climate change is a virus

March 10, 2024 2:51 PM

Cows: Nature's enemy. By turning grass into methane, cattle threaten to kill us all. But we know the cows themselves are not to blame; there are bacteria within their guts producing the methane. Now, scientists investigate the viruses lurking within the bacteria, that make methane production possible. "Microbial viruses act as secret drivers of climate change, new study finds."

BONUS COW-PHOBIC MATERIAL: "New report outlines microbial solutions to mediate methane emissions."

posted by mittens (35 comments total)

I like it.
Fuck cows and their stinky farts!
(Also it hints at The Swarm where methane-eating ice-worms something something Gaia raises hell on humanity... and there's fish involved(?))
posted by From Bklyn at 3:35 PM on March 10 [1 favorite]

It's not always the "stinky farts" that produce the methane, but also the "herbaceous burps".
posted by rum-soaked space hobo at 3:59 PM on March 10 [2 favorites]

I can't not hear this post's title in William S. Burroughs' voice.
posted by doctornemo at 4:15 PM on March 10 [9 favorites]

(Context: background on methane vs CO2 as a driver of climate change. Includes some data about sources of methane.)
posted by eviemath at 5:09 PM on March 10 [1 favorite]

Oops, a planet overrun with cows has turned out to be a bad idea.

Wait, y'all are paying the farmers to make even more???

Could you not?
posted by tigrrrlily at 5:27 PM on March 10 [5 favorites]

The carbon emitted by cattle directly (as the product of enteric fermentation in the rumen) and indirectly (through waste) isn't new carbon, it's part of the global carbon cycle. The carbon that's going to kill us all is carbon that once was sequestered and has now been released into the environment, largely through fossil fuel consumption. This is a really important distinction that's often missed in these conversations. While I work with cows in a professional capacity, it's true that the livestock sector can do better. However, we're already doing better than you might suppose.

The greatest challenge lies in many low- and middle-income countries which have large numbers of cattle that haven't been genetically improved. There are often cultural, religious, and economic factors at play, and they interact in complex ways.

Fossil fuels will kill us long before cows will.

Some peer-reviewed references, copies available upon request:

von Keyserlingk et al. 2013. Invited review: Sustainability of the US dairy industry.

Capper and Cady. 2019. The effects of improved performance in the U.S. dairy cattle industry on environmental impacts between 2007 and 2017.

Peterson and Mitloehner. 2021. Sustainability of the Dairy Industry: Emissions and Mitigation Opportunities.

Place et al. 2022. Symposium review: Defining a pathway to climate neutrality for US dairy cattle production.

del Prado et al. 2023. Animal board invited review: Opportunities and challenges in using GWP* to report the impact of ruminant livestock on global temperature change.

El Mashad et al. 2023. Anaerobic Digestion and Alternative Manure Management Technologies for Methane Emissions Mitigation on Californian Dairies.
posted by wintermind at 5:27 PM on March 10 [27 favorites]

04-15-14
These Backpacks For Cows Collect Their Fart Gas And Store It For Energy

"Each cow apparently passes enough gas to power a car or a fridge. Imagine the possibilities."
posted by clavdivs at 5:42 PM on March 10 [2 favorites]

Climate change is also spreading the ticks that spread alpha-gal syndrome, so eventually this will be self-correcting?
posted by rikschell at 5:54 PM on March 10 [4 favorites]

It seems like a good option might be for humans to stop eating cows. I mean, we can still eat other animals, just maybe not the big farting ones?
posted by OrangeDisk at 6:09 PM on March 10 [1 favorite]

We have a plan to move cattle production into orbit, so the carbon can be safely vented into space. We’re going to call it “The Herd Shot ‘Round the World.”
posted by GenjiandProust at 6:13 PM on March 10 [41 favorites]

Burroughs voice.

We have a plan to move cattle production into orbit,
The Hundred Year Plan.
posted by clavdivs at 6:29 PM on March 10 [2 favorites]

The carbon emitted by cattle directly (as the product of enteric fermentation in the rumen) and indirectly (through waste) isn't new carbon

The problem is that they're not converting embodied carbon into CO2, which is how the carbon cycle typically works – they're converting it to methane, which is more than 28 times as potent of a greenhouse gas as CO2.

The good news is that Methane eventually breaks down in the atmosphere, which means that things actually will get better somewhat quickly if we can find a way to reduce cow farts.

But in the interim, Methane is bad, and finding ways to leak less of it into the atmosphere has an incredible bang for the buck, even if it means just burning it. Believe it or not, those oil fields flaring off excess Methane are actually doing a favor to the environment, compared to the alternative.
posted by schmod at 7:36 PM on March 10 [19 favorites]

It seems like a good option might be for humans to stop eating cows. I mean, we can still eat other animals, just maybe not the big farting ones?

Alternately eat them all, right now, in some sort of insanely gigantic global potlatch.
posted by AdamCSnider at 7:47 PM on March 10 [7 favorites]

Metafilter: things actually will get better somewhat quickly if we can find a way to reduce cow farts
posted by dephlogisticated at 9:27 PM on March 10 [6 favorites]

Yes, it's clearly the cows' fault, not humans. Carry on everyone! Just eat a little less beef, and we'll all be fine.
posted by Anoplura at 12:29 AM on March 11 [2 favorites]

The methane *is* short lived but it's also being constantly replaced, and there's a vast amount of it. It's like having a stack of bricks in an overflowing bath that you can quickly remove to lower the water level. But to remove the bricks, you have to stop farming such a vast, unsustainable number of cows, and despite the few articles linked to above, that is the global scientific consensus. Yes, fixing the tap is also needed.

The key cultural aspect involved here is certain countries obsession with eating an incredibly resource intensive type of food, which as well as producing huge amounts of methane, requires vast amounts of land, huge amounts of feed, deforestation, genocide, and shitting so much entire ecosystems collapse. Oh, and the water too, entire river systems and water tables are vanishing.

And "grass fed" beef at current quantities would require us to find entire new planets to fill with cows.
posted by BinaryApe at 1:23 AM on March 11 [3 favorites]

Lest we blame the farting cows too much we should also note that humans have any number of up to 140,000 types of virus acting on the bacteria in our own guts- at least 70,000 of which were classified as "previously unknown" in 2021. Presumably most of these are beneficial - so "beneficial virus" should be permitted to stand alongside "beneficial bacteria" in our understanding of digestion.

Specifically with cows: if scientists are able to find a way of changing the virus mix - so as to change the bacterial action - hence to remove/reduce the methane emissions - that would be a real achievement.
posted by rongorongo at 2:04 AM on March 11 [1 favorite]

isn't this like saying that a cough is a virus? or that a runny nose is a virus?

those are symptoms of a viral infection...

these elevated cow, methane, and CO2 levels, and the resulting climate change are symptoms of viral infection.

humans are the virus.

anyhow, eventually the earth will shake off this human infection, and regain it's natural balance, at least over geologic time scales.
posted by winston smith at 3:43 AM on March 11 [1 favorite]

Specifically with cows: if scientists are able to find a way of changing the virus mix - so as to change the bacterial action - hence to remove/reduce the methane emissions...


Or, better still, develop a microbiome that consumes CO2/Carbon. And then I guess the poops would be very, uh, calciferous... and could maybe then be used in cement production... (This is an idea based on exactly zero knowledge or understanding of how CRISPR or Cow guts work. So, you know, caveat lector.)

There have been a number of strategies to harvest the cow farts and then extract the hydrogen from them, and use this to make power. (and also changing feedstock to reduce methane.) Harvesting farts. Fart harvesters. Brings a whole new dimension to "Git along little doggie"
posted by From Bklyn at 3:46 AM on March 11 [1 favorite]

A cow fart is just a virus's way of making another virus.
posted by JohnFromGR at 4:02 AM on March 11

And "grass fed" beef at current quantities would require us to find entire new planets to fill with cows.

I love a dreamer with VISION!

(And you know how we're going to fuel the rockets to get us there? METHANE!)
posted by wenestvedt at 6:34 AM on March 11 [4 favorites]

the production of cows is also a huge driver in "land use change" aka burning down rain forest and plowing under high grass prairie to grow the feed for those cows.

Not only are these large ungulates burping large amounts of heat trapping methane, but we are cutting down carbon sinks to grown food to feed them. Food that would be much more efficiently used to feed humans.

The types of places they cut/burn down to grow this feed is often not very good at growing it, so once the stored nutrients in the soil are gone, they have to move on to more forest and burn/cut it down. The capital gains from this can go on until we run out of forest, and there are only incentives for the poor to keep doing this because its the only way for them to make money.

In my mind the only sustainable way to grow any significant amount of large herbivores, is to mimic what a large herd of bison would do. Have them always on the move over grasslands so that they actually help store carbon in the soil (the way herds of bison and high grass prairie do). But that would require A LOT of space, and we would need to leave all that carbon in the ground instead of plowing it into corn and soy beans.

Only a living ecosystem is going to store the carbon we need, and keep it stored. So unless we want to turn a large part of the middle of the US back into a high grass prairie that occasionally catches on fire....we probably should just stop growing so many cows.

All of this would take a market that was heavily controlled by a central body of world governments, and would need to strictly reign in the capitalists driving these negative feedback loops. Even though it would probably save all of us from the horrific effects of global warming, a lot of folks are just going to go "SOCIALISM!" and run screaming in the other direction. We can and should solve these issues, but its going to take a lot of political power, a lot of organizing, and a lot of work for many hundreds of years.
posted by stilgar at 7:23 AM on March 11 [7 favorites]

Brings a whole new dimension to "Git along little doggie"

I can't get along little doggie!
I can't even get one that's small...
posted by We put our faith in Blast Hardcheese at 9:30 AM on March 11 [1 favorite]

The carbon that's going to kill us all is carbon that once was sequestered and has now been released into the environment, largely through fossil fuel consumption.

Cattle are a huge driver of fossil fuel consumption.

It takes an estimated 2-3 calories of fossil fuel to produce 1 calorie of protein from soybeans, corn, or wheat. For beef it takes 54 calories of fuel to produce 1 calorie of protein.

Over 8 liters of gasoline is required to produce one kilo of grain-fed beef.

If the specious red herring that cows are part of the "biogenic carbon cycle", in contrast with fossil fuels, helps you sleep at night as a steak-a-day eater or beef producer, it shouldn't. Cows produce terrifying amounts of methane and consume terrifying amounts of fossil fuels.
posted by gurple at 9:33 AM on March 11 [6 favorites]

Many wild animals are ruminants as well who produce methane. Cattle ranching and other land use changes, along with deliberate policies like the destruction of the American buffalo, have dramatically reduced the number of wild ruminants. Reducing the number of cows reduces methane only insofar as we also prevent those wild ruminant populations from rebounding, which also means preventing the carbon sequestering ecosystems they maintain from rebounding.

There’s a lot wrong with the meat industry, but focusing on cow burps instead of fossil fuel companies is a distraction from the real issues we need to deal with to mitigate climate change.
posted by congen at 9:34 AM on March 11 [3 favorites]

Engineer a gut virus that converts to CO2 or Oxygen instead. We need to be doing a lot more bioengineering and terraforming, possibly through bioengineering to survive this doomed rock. Climate change is our easiest extinction hurdle and we should be working through the next ones while working through this one.
posted by GoblinHoney at 10:57 AM on March 11 [1 favorite]

This research is fascinating though - it feels a bit like parasite research in ecology where these small things we don’t usually think of as major ecosystem actors really are!
posted by congen at 10:59 AM on March 11

so it's viruses in the bacteria that lead to the farts?

and I thought blaming the dog was clever
posted by elkevelvet at 11:01 AM on March 11 [1 favorite]

Reducing the number of cows reduces methane only insofar as we also prevent those wild ruminant populations from rebounding

Wait, what? Are you suggesting that, if cattle ranching stopped tomorrow, additional wild ruminants would appear in numbers equal to our current cattle? Why would that happen? How would that happen?
posted by gurple at 8:19 PM on March 11 [2 favorites]

people hiding cows.
posted by clavdivs at 8:23 PM on March 11 [2 favorites]

Well, currently wild ruminants populations are suppressed by land use changes - like competition with cattle, or enormous swaths of prairie being used to grow corn. If we stop doing that and start restoring some of the more degraded landscapes (i.e. the entire corn belt), then we would see dramatic increases in bison and other ungulate numbers - like pronghorn in the southwest.

You can read a bit about historic range contractions of North American ungulates in this paper - https://academic.oup.com/bioscience/article/54/2/123/255016

It would not happen overnight, but population growth is exponential growth and if we got real serious about it, we could see incredible changes in my lifetime.

But this is quite apart from the virus article - i can imagine changing feed or medicating cattle to deal with the viruses increasing methane production. It’s hard to imagine applying that in wild populations.
posted by congen at 9:10 AM on March 12

There is simply no way that allowing the area currently used for cattle to revert to a wild state would result in bison and other ungulates rebounding to levels that would replace the methane from those cattle. Bison were not as dense on the ground as cattle are in North America and we have of course converted a lot of that land to other types of agriculture. And the methane contribution from deer and similar ungulates is just not going to be that significant.
posted by ssg at 4:29 PM on March 12 [2 favorites]

We definitely need kill all our cattle, not just alter their gut microbes. Ain't worried about wild ruminants but if they become problematic then we've pleny of people who really love killing them.

Aside from land use change, the work discussed here would mostly be used to ficticiously count methane producing cattle as non-methane producing cattle, so like CCS but for cattle ranchers (previously).

It's too bad mad cow disease winds up so extremely non-virulent. Could someone genetically modify cattle bacteria to catalyze the BSE prions? I suppose cattle gut bacteria must commonly spread via the fecal-oral route, no?
posted by jeffburdges at 11:01 AM on March 15

> Or, better still, develop a microbiome that consumes CO2/Carbon.

Be careful what you wish for: the exact methane-producing archaea (methanogens) that we're talking about in gut microbiomes do in fact consume CO2! However, as part of CO2 consumption, they produce methane from any carbon that doesn't get incorporated into their biomass. (They also have some very specific needs for hydrogen, among other things.) So unfortunately, it gets more complicated than "1. consume CO2, 2. ..., 3. profit!"

I also suspect you're thinking of this patent and related projects, which have been focused on harvesting methane (not hydrogen) from cow belches. Flatulence is actually the lesser contribution to bovine emissions. Some of these proposed cow backpacks have involved the use of methane-consuming bacteria ("methanotrophs") to process the emissions in situ.

> Engineer a gut virus that converts to CO2 or Oxygen instead.

And something similar applies here. There are indeed methanotrophs, microbes (bacteria and archaea) which oxidize methane; any carbon that they don't incorporate into their biomass gets excreted as CO2. But, well, CO2 production is still not great. And the more common types of methanotrophs require oxygen in order to do this, and the parts of our guts - and cow guts - that harbor methane-producing microbes are anaerobic, i.e. little to no oxygen. The less common type of methanotroph can work without oxygen, but they absolutely require some very specific buddy microbes in order to carry out this chemistry. And as you can perhaps imagine, if it is challenging to make sure you have the right amount of one strain maintained in a gut environment, it can be more challenging to make sure that two are. (There are a few other oddballs, e.g. one that needs nitrite, but they're all still CO2 producers.) So unfortunately, this also turns out to be more complicated than "1. consume CH4, 2. ..., 3. profit!" (You can't convert methane (CH4) directly to oxygen (O2) without some sort of alchemy that does not exist in any useful way; dioxygen by definition shares no types of atoms with methane.)

So yes: there absolutely are academic and industrial groups working on engineering both methane-consuming/CO2-producing and CO2-consuming/methane-producing microbes in a range of ways! But, unfortunately, it's not as straightforward as one might wish.
posted by ASF Tod und Schwerkraft at 11:57 PM on March 15 [2 favorites]

...probably no one is reading this, but someone was wrong (or at least insufficiently accurate) on the internet! Specifically, the summary in the "secret drivers of climate change" link is... not great, to the point of being sorta misleading. Taking a look at the actual paper:

Genes associated with methanogenesis (methane production) and methanotrophy (methane consumption) have been located in some viral genomes, despite the fact that those pathways are associated with archaea and bacteria. Interesting! But... importantly, what's detected are mostly single genes, not the full suites of genes necessary for these metabolic pathways. Based on various kinds of evolutionary analyses, we already knew that these sorts of genes were passed between species (to some extent) via horizontal gene transfer, likely including virus-mediated transduction. This is especially the case for genes associated with methane consumption. The nifty thing about this paper is that we can sorta see viruses caught in the act - but it's not something that we didn't know was possible, and importantly, for the question of methane production, the methanogens found in gut microbiomes are predominantly lineages of microbes that are well-established methane-producers, not new methane-producers. Receiving one of these genes without the rest of the pathway from a virus would not make a microbe into a new methane-producer or methane-consumer, so these viruses are not making new methane-producers in an otherwise methane-free environment! And the phys.org summary does have one of the authors stating near the end: "Despite this, there isn't any evidence that these viruses directly encode methane metabolism genes themselves, suggesting that viruses' potential impact on the methane cycling varies by their habitat, said Zhong." (I'd argue that the paper has not actually shown that the viruses have any direct impact on methane cycling, so the adjective "potential" is doing a lot of work there.)

The analysis of the "genes that modulate host metabolisms" is purely in silico, and the 13 "auxiliary metabolic genes" they highlight aren't actually connected directly to methane metabolism but to a grab bag of processes connected to "energy, carbohydrates, amino acids, nucleotides, cofactors, and vitamins" (e.g. bacterioferritin, which is certainly relevant to iron homeostasis, but only a vanishingly small number of microbes don't need iron for key metabolic processes, so this says little about methane metabolism specifically.) Not implausible hypotheses, but the actual data are not evidence of direct viral modulation of anything, let alone anything methane related.

The paper itself unfortunately obscures all of this a little. In general, it (to a certain extent) conflates "probably these genes encode proteins that could be functional if they were produced" and "there seems to be some selective pressure towards preserving these genes" with both "the proteins are in fact produced" and "the proteins produced probably have a (direct and significant) role in methane metabolism." But all of those are not the same thing! The phys.org summary only exacerbates this.

The authors also make a few iffy arguments, proposing their results have specific relationships to viral survival: for example, they claim that pmoC (which encodes a protein that forms part of a methane oxidation enzyme) must be more important for viruses than pmoAB (which encode the rest of the enzyme), since they don't see the latter... but microbial genomes often have more copies of pmoC than they do of pmoAB, so it's not entirely clear the extent to which this reflects much more than the abundances of the gene in the genomes. One of the papers they cite is actually rather more convincing about a real-life role for these specific viral genes - but despite having more experimental data for the in vivo use of the viral pmoC genes, this second paper suggests that the viral genes may have roles analogous to the "extra" genomic pmoC copies (i.e. may affect relative levels of methane oxidation under specific conditions but aren't necessarily required for it under all conditions), and they discuss the potential role(s) of PmoC in the context of microbes that already encode methane oxidation pathways (i.e. viruses with this gene do not on their own turn non-methane-oxidizers into methane-oxidizers). But this represents only one of the genes discussed in the first paper, and the net effect of these virally encoded genes are unclear even in this one more thoroughly explored example. (We certainly know that single cultures of methanotrophs do not rely on these viruses to oxidize methane.) Given the low numbers of some of the genes detected in the first paper, "we need to sequence more" is probably the null hypothesis I'd want to disprove. And absent more data, I don't think we have solid reasons to assume that the collective results of this first paper actually reflect a significant direct influence of viruses on current methane levels (vs. a much more indirect role more associated with the long term direction of methanotroph and methanogen evolution.)

The whole "more methane metabolism genes are associated with the rumen!" thing is also a little potentially misleading; metageneomes from rumens (anaerobic environments) were almost a third of the dataset to begin with, and they don't address which of their other samples were from low vs. high-oxygen environments (even the ones they collected, let alone ones published by others) and what the methane levels were. Given that methane production is (primarily) anaerobic (needs oxygen to be absent) and methane consumption is (primarily) aerobic (needs oxygen), and the latter is only going to be seen in areas with a certain amount of methane, this has the potential to bias their datasets - particularly when in some cases (fae, fwdF) the gene was detected in a single assembled viral sequence.

So is this evidence that these viruses can indeed help pass around genes related to methane metabolism? Sure, and that's nifty! Does it actually establish that these viruses are playing a significant direct role in changing global methane metabolism on a scale and timeframe that's relevant to global warming, with or without cows? I'm not really convinced - based on the data actually presented - that they've shown this. (That other paper they cite on PmoC is more convincing, but 1) it's related to one specific type of methane consumption, 2) it's still unclear what the net effect - if any - is even within one cell, and 3) it's even more unclear how globally relevant it is.) So I'd be real cautious in taking this paper as strong evidence that the viruses under discussion are actually driving climate change in any way whatsoever.
posted by ASF Tod und Schwerkraft at 12:28 AM on March 16 [4 favorites]