2296: Sourdough Starter

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Sourdough Starter
Once the lockdown is over, let's all get together and swap starters!
Title text: Once the lockdown is over, let's all get together and swap starters!


This comic is another comic in a series of comics related to the 2020 pandemic of the coronavirus SARS-CoV-2, which causes COVID-19.

Recently, because of the coronavirus, many people are forced to stay home in quarantine or under Stay-at-home orders. These conditions often lead to spare time that needs to be filled, and many people have turned to baking, which can usually be done entirely at home, is relatively time-consuming, and has the advantage of producing finished food, lessening the need to go out to buy food. This trend is common enough that baking supplies, including yeast, have seen a spike in demand, to the point where many people have trouble finding it.

As an alternative to yeast, consumers can grow their own sourdough starter, which is a symbiotic culture of yeast and bacteria naturally found in flour. Once the starter has matured, part of it can be used to make bread or other baked good rise, while the remainder can be mixed with more water and nutrients to allow the remaining yeast and bacteria to multiply once again. Because these populations need to be maintained, it's often been a practice to trade starters from house to house, with each home using starter when they need it, then setting up the remaining starter to breed more. This has historically been a social activity, allowing people who share an interest in baking to meet, share recipes, and spend time together.

The upshot of all of this is that the coronavirus pandemic has created conditions in which yeast (and symbiotic bacteria) are being bred in larger numbers, both by companies trying to fill demand, and by individuals trying to make their own. The joke is that this outcome is, in fact, the entire purpose of the coronavirus, which is in a symbiotic relationship with yeast. The entire global pandemic, by this logic, is directed to keep humans indoors and baking so that more yeast (and bacteria) is bred. The practice of swapping sourdough starters means that they're propagated more widely, increasing and distributing the yeast population (while potentially giving the virus more opportunity to spread, as people socialize).

As Randall points out, this cycle is extremely convoluted. However, it is not unknown for parasites to drive the responses of other creatures in order to propagate themselves. For example, Toxoplasma gondii infects mice, but can only reproduce when it infects cats. The organism has therefore adapted to infect the nervous systems of mice, making them extremely reckless, increasing their odds of being caught and eaten by cats, allowing the the parasite to move to a new host. Some flatworm parasites have very complex life cycles that involve four different host animals.

Randall has previously speculated about unusual parasitic organisms in 2246: Christmas Presents, in which he "concluded" that Christmas presents are parasites of Christmas trees, possibly mediated by a fungus. And in 1664: Mycology a fungus infects human brains making them wish to study (and thus grow more of) this fungus.

Viruses are not organisms (lacking some of the defining features of life), and it is debatable whether they would be considered parasites. Moreover, this theory is obviously implausible for a number of reasons. The most obvious being that natural responses, particularly of viruses and simple organisms, evolve over a long time scale. SARS-CoV-2, the virus responsible for the current pandemic, has very likely been infecting humans for less than one year, certainly not long enough to evolve such a complex set of behaviors. At the same time, a symbiotic relationship would require yeast to somehow contribute to the life cycle of the coronavirus in a meaningful way, which is unlikely when the yeast is being artificially bred in isolated containers. If however, as suggested by the title text, people getting together to swap yeast starters after the lockdown ends does cause the virus to begin spreading in humans again as a result of the social contact, then the yeast would be contributing to the life cycle of the coronavirus, in an equally convoluted way. The humor, therefore, is derived from the fact that this is a comical exaggeration, but based on cycles that actually do happen in nature.


[Cueball stands in front of a kitchen counter looking down at a glass jar he is holding in both hands. The jar's flat lid is lying on the table. There is another large jar farther back on the counter with a lid, with a small handle, on. In both jars there is a substance, which do stay in the same position in the jar even though Cueball tilts the jar he is holding.]
Cueball: My sourdough starter is coming along nicely!
[Caption below the panel]
Theory: The coronavirus is a yeast symbiont with an extremely convoluted parasitic life cycle.

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Symbiosis is good for the species involved in that relationship, but it may still be harmful to other organisms. What Randall is suggesting is that humans are collateral damage. Barmar (talk) 21:37, 20 April 2020 (UTC)

Is there controversy around covid-19 coming from cave bats rarely visited by humans, or would the bats be part of the convoluted lifecycle? 22:02, 20 April 2020 (UTC)

Is this comic suggesting the yeast would allow the virus to survive without a human host, and when we later swap sourdough starters the virus could then find a new human host to infect? Ianrbibtitlht (talk) 01:05, 21 April 2020 (UTC)

The virus and yeast can have working symbiosis without ever coming into physical contact. It's just that the lockdown probably ends before the virus will be actually eradicated, so large meetings just after end of lockdown is not good idea. -- Hkmaly (talk) 22:19, 21 April 2020 (UTC)

That is not a theory in the caption. It has no evidence and makes no testable predictions, at least as far as I can tell. It is just a hypothesis. Nutster (talk) 01:56, 21 April 2020 (UTC)

Maybe not a theory in the real world, but this isn't the real world. Perhaps in the world of this comic there is evidence and there were predictions that have been tested, making it a theory to Cueball. Ianrbibtitlht (talk) 02:17, 21 April 2020 (UTC)
With a bit of reading online, I've discovered that your definition of "theory" is but one of many different definitions of the word. In some contexts, theory is synonymous with hypothesis, according to Merriam-Webster. Ianrbibtitlht (talk) 02:31, 21 April 2020 (UTC)
Theory: This comic is the same category as "My hobby". Aka: It's a joke. Elektrizikekswerk (talk) 07:21, 21 April 2020 (UTC)
"theory - noun - an idea used to account for a situation or justify a course of action" - that seems to describe how Randall used the word Barmar (talk) 14:03, 21 April 2020 (UTC)

In the UK at least, it's been too successful. You can't get flour in the shops most times. Apparently, most flour goes into big sacks for bakeries and the like. The mills haven't been able to gear up their production of small bags for domestic use. 09:24, 21 April 2020 (UT

My pet theory, before Boris Johnson got a bit better and didn't relax measures, was that COVID had deliberately infected half the Cabinet in order to gain the authority to infect everyone else, like common Pod People tropes would have happen. (That didn't happen, but maybe it's just being more clever. Like causing the PPE supply chains to break under the strain.) 10:46, 21 April 2020 (UTC)

Isn't "swapping starters" a Pokemon reference? You know, getting together and trading starter Pokemon until everyone has all 3. Daevin (talk) 14:53, 21 April 2020 (UTC)

I assumed this was a continuation of the previous comic: precise number + garbage = garbage; perfectly good flour + sourdough starter = garbage that tastes so bad not even microbes want to eat it.

Bakers gonna bake, Haters gonna hate... Tier666 (talk) 09:48, 22 April 2020 (UTC)

Have to confess: The yeasts (and lactobacilli) got me - still waiting for the virus. Tier666 (talk) 09:48, 22 April 2020 (UTC)

I wonder if this point (that lactobacilli are an important part of sourdough should be added to the actual explanation above.Tovodeverett (talk) 14:37, 23 April 2020 (UTC)

Sourdough fanatics insist, despite solid evidence to the contrary, that the yeast strains in their carefully maintained starter material are identical to those present when their greatgreatgrandmother started the very first batch. Stuff flies in through the window, or off your fingers, or whatever, every time the starter is exposed to air. Whatever -- the final product still tastes great. And after all, "Viruses HATE This One Simple Trick To Kill Them" : bake to kill off everything in the dough. Cellocgw (talk) 10:48, 22 April 2020 (UTC)

I wouldn't say I'm a fanatic at any level, but we do make sourdough pancakes on a semi-regular basis. I recognize that the starter I have maintained for 20+ years has altered over time through the introduction of new strains and possibly through mutation, but it is still linked to the starter I received. After all, I still consider myself to be me after 40+ years! I received the starter from my mother, who in turn received it from a family that received it from a family (and so on) with the claim that it traces back to the Alaska Goldrush days. We have no way of knowing for certain if the claim is true, but since we live in Anchorage, it might actually be true. I also like to think of all the evolutionary bottlenecks my starter has gone through - we sometimes go 6 months with it barely hanging on in the fridge, and I keep two copies running in parallel as a safety net, but I suspect lengthy periods of fridge life have definitely shaped the starter to be fridge resilient. It gets a little funky, and I've lost one copy from time to time and had to fork from the other, but a month stretch of sustained weekly pancake making has it back in good form. So maybe Randall's not that far off - my starter knew it was getting sketchy and called in COVID-19 to save it! And furthermore, I forked it and sent a copy to live with a friend, so now there's more redundancy in the network! And we're all making pancakes and smiling at the bubbly froth in the morning!Tovodeverett (talk) 14:37, 23 April 2020 (UTC)