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==Explanation==
 
==Explanation==
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{{w|Cicada|Cicadas}} are a species of insect whose nymphs burrow underground and emerge as adults to reproduce several years later.  One common species in North America is the 17-year cicada, also known as the {{w|periodical cicada}}. These cicadas form distinct {{w|Periodical_cicadas#Map_of_brood_locations|broods}} which burrow and emerge as a group every 17 years, with different broods starting the cycle at different times.  This results in a couple of weeks every 17 years when the cicadas swarm in huge numbers, then vanish just as quickly when the adults die off.  Cicadas also make a distinctive buzzing sound, which makes their periodic appearance even more memorable.
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{{w|Cicada|Cicadas}} are a species of insect whose nymphs burrow underground and emerge as adults to reproduce several years later.  One common species in North America is the 17-year cicada, also known as the {{w|periodical cicada}}. These cicadas form distinct {{w|Periodical_cicadas#Map_of_brood_locations|broods}} which burrow and emerge as a group every 17 years, with different broods starting the cycle at different times.  This results in a couple of weeks every 17 years when the cicadas swarm in huge numbers, then vanish just as quickly when the adults die off.  Cicadas also make a distinctive buzzing sound, which makes their periodic appearance even more memorable.
  
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In the comic, [[Cueball]] and [[Ponytail]] have accidentally created 17-''second'' cicadas using {{w|genetic engineering}}.  This means that rather than seeing a massive swarm every 17 years that lasts for a few weeks, they have to deal with a swarm every 17 seconds that lasts for a few moments. This makes it very difficult for them to do their work, especially to figure out how the cicadas were created because the swarm keeps interrupting their work. Note that the comic has been drawn differently to most other straight four-panel comics, probably to highlight the interruptions of the buzzing swarm - see the [[#Transcript|transcript]]. Also see the [[#Trivia|trivia section]] below for more details on the 17-year cicadas. Those were referenced again in the title text of [[2633: Astronomer Hotline]].
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The widely-accepted scientific explanation for the long and seemingly arbitrary 17-year lifecycle is that seventeen is a {{w|prime number}} - it's believed that this is an evolutionary adaptation to prevent the lifecycles of predator populations from synchronizing with the cicada's, since 17 cannot be divided by anything other than itself and 1. This would also explain why some broods of cicada have 13-year lifecycles (the next lowest prime number).
  
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It's worth noting that every 17th word in the comic is "bzzzzzzz", implying that every word spoken takes one second. The caption also includes 17 words (if "17" is one word).
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In the comic, [[Cueball]] and [[Ponytail]] have accidentally created 17-''second'' cicadas using {{w|genetic engineering}}.  This means that rather than seeing a massive swarm every 17 years, they have to deal with a swarm every 17 seconds. This makes it very difficult for them to do their work, especially to figure out how the cicadas were created, because the swarm keeps interrupting their work. Note that the comic has been drawn differently than most other straight four panel comics, probably to highlight the interruptions of the  buzzing swarm - see the [[#Transcript|Transcript]].
  
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The title text is a pun on "{{w|circadian rhythm}}." In particular, it might resemble something said to someone getting adjusted to a new sleep schedule. But here it is the 17 seconds interruption, not a time zone shift, that has to be adjusted for.  
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It is not explained why Cueball and Ponytail are tinkering with cicada genes, but their wings are {{w|superhydrophobic}} and antibacterial due to nano-scale structures on their surfaces.  Their ability to hibernate may also be of interest in medicine.  One technique for understanding which genes are responsible for various traits is by "{{w|gene knockout|knocking out}}" genes and seeing what is affected. In this case, it looks like a gene has had a nucleotide duplicated, which would change every amino acid in that protein after the duplication error, and the resulting malformed protein has caused the hibernation period of the modified cicadas to be extremely short.  Perhaps the protein is involved in the "year counting" function, so that the cicadas wake up almost as soon as they enter hibernation, rather than waiting seventeen years.
  
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This entire comic seems to only have been a lead-up to the "cicadian rhythm" punchline. This is an interesting suggestion since [[Randall]] has mentioned in an interview that he makes up the title text after completing the comic.{{Actual citation needed}} Seems like he made an exception here; unless he didn't.
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The title text is a pun on "{{w|circadian rhythm}}." In particular, it might resemble something said to someone getting adjusted to a new sleep schedule. But here it is the 17 seconds interruption not a time zone shift that has to be adjusted for.
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This entire comic seems to only have been a lead-up to the "cicadian rhythm" punchline. This is an interesting suggestion since [[Randall]] has mentioned in an interview that he makes up the title text after completing the comic.{{Citation needed}} Seems like he made an exception here; unless he didn't.
  
 
==Transcript==
 
==Transcript==
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:[This comic is laid out in a variation of a regular four-panel comic. One wide panel is overlaid by two smaller panels, which are placed where the second and fourth panels would be. These panels are slightly offset so they extend above the wide panel.]
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:[A special design has been used for this comic. One large broad panel is interrupted by two smaller normal sized panels lying on top of it, but slightly offset so they extend a bit above the long panels upper border. But at the bottom it is thus clear that there is indeed one large panel. The large panel have one drawing before the first and one drawing between the two panels on top of it. But these two drawings act like two separate panels between the others, and is thus not to be seen as something ongoing at the same time in the large panel. The reason for doing it this way, is likely to show how interrupting the cicadas swarms are, in each of the two panels lying on top of the large panel. But for the story lines continuity, the comic could just have consisted of four normal independent panels instead. Here below the four individual drawings are transcribes as if they where four normally separate panels.]
  
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:[Cueball and Ponytail are facing each other across a desk while having a conversation. Cueball is holding up a tablet in his hand while Ponytail is typing at a laptop on the desk.]
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:[Cueball and Ponytail are facing each other across a desk. Cueball is holding up a tablet in his hand while Ponytail is typing at a laptop standing on the desk.]
 
:Cueball: What can you tell from genome comparison?
 
:Cueball: What can you tell from genome comparison?
 
:Ponytail: I think there's a duplication on the -
 
:Ponytail: I think there's a duplication on the -
 
:Ponytail: ''Look out!''
 
:Ponytail: ''Look out!''
  
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:[An overlaid panel shows that the air is full of flying cicadas, many of which have landed on Cueball, Ponytail, the laptop, the tablet, and the desk. Ponytail and Cueball have their arms up in a futile attempt to shield themselves from the bugs, with Cueball having put the tablet down on the table.]
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:[The air is full of flying bugs, many of which have landed on Cueball, Ponytail, the laptop, the tablet and the desk. Ponytail and Cueball have their arms up in a futile attempt to shield themselves from the bugs, Cueball managed to put the tablet down on the table first.]
 
:<big>'''''Bzzzzzzz'''''</big>
 
:<big>'''''Bzzzzzzz'''''</big>
  
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:[The cicadas are gone, and Cueball and Ponytail resume their conversation. Cueball has picked up the tablet again]
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:[The bugs are gone and Ponytail and Cueball are again conversing. Cueball has taken the tablet slightly up above the table again.]
 
:Ponytail: - a duplication on the gene right before the cleavage site, so the resulting protein -
 
:Ponytail: - a duplication on the gene right before the cleavage site, so the resulting protein -
 
:Ponytail: ''Look out!''
 
:Ponytail: ''Look out!''
  
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:[An overlaid panel shows that the air is again full of flying cicadas, which have once again landed on Cueball, Ponytail, the laptop, the tablet, and the desk. Ponytail and Cueball have raised their arms to shield themselves again.]
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:[The air is again full of flying bugs, many of which have landed on everything. Ponytail and Cueball are again trying to shield themselves, leaving tablet and laptop alone on the table.]
 
:<big>'''''Bzzzzzzz'''''</big>
 
:<big>'''''Bzzzzzzz'''''</big>
  
 
:[Caption below the large panel:]
 
:[Caption below the large panel:]
 
:Our genetics work has produced 17-second cicadas, but we're having a hard time figuring out how.
 
:Our genetics work has produced 17-second cicadas, but we're having a hard time figuring out how.
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==Trivia==
 
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The widely-accepted scientific explanation for the long and seemingly arbitrary 17-year lifecycle is that seventeen is a {{w|prime number}} - it's believed that this is an evolutionary adaptation against lifecycles of competitors taking easy advantage of the cicada as a food source (if a predator) or emerging early to dominate their shared food source (if a fellow feeder), since 17 years cannot be divided by any whole number of years other than itself and 1.
 
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A 16-year cicada might find a creature with an 8-year, 4-year, or [[1602:_Linguistics_Club|biennial]] cycle could profit from it in a 'clash' of expectations, but only a cycle that is a multiple of 17 (by an identical accident of evolution, that must also match the 'beat' years of the Cicada to be useful) would affect the presumed ancestors of the comic-strip breed. Predators often work to yearly cycles of plenty and scarcity of food or can survive a low number of famine years between the better ones, but if they have less than one year of 'bounty' for every decade or so of 'normal' feeding then they cannot build up the numbers needed to threaten such prey that plays the long-game.
 
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Other broods of cicada have 13-year lifecycles (the next lowest prime number), and would potentially clash for resources (or hybridize) only every 221 years. Even if this causes a single bad cycle, for both sub-species, the next cycle of appearance is their own once more (for each) and the respective populations have plenty of opportunity to recover from this event by the time a further two centuries pass.  Thus it is theorized the happenstance evolution of a period of dormancy that gives a cycle of a significantly large prime-number of years - though still low enough to ''survive'' that period - is ultimately more advantageous than any cousins who tried to evolve to a period with smaller factors/shorter harmonics.
 
  
 
{{comic discussion}}
 
{{comic discussion}}

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