explain xkcd - User contributions [en]

3252: Ancestral Genomes

2026-05-29T19:48:06Z

Kleinesfilmröllchen: Complete transcript (tree diagram should be explained in more detail in the explanation)

{{comic
| number = 3252
| date = May 29, 2026
| title = Ancestral Genomes
| image = ancestral_genomes_2x.png
| imagesize = 299x416px
| noexpand = true
| titletext = SUGGESTIONS FOR FUTURE RESEARCH: No further research is needed as it is frankly none of our business.
}}

==Explanation==
{{incomplete|This page was created by a scientist respecting the comic’s privacy. Don't remove this notice too soon.}}

A [[wikipedia:Genotype|Genotype]] is the complete genetic makeup of an individual, i.e. all of its genes. In humans, genotypes are almost always inherited from an individual’s parents; the two parents’ genotypes combine during sexual reproduction to form the genotype of the child. Only in very rare circumstances does a genotype arise by genetic [[wikipedia:Mutation|mutation]], where parts of the DNA change randomly in a way that gives rise to a new genotype. Depending on the behavior of the mutation, it may spread throughout a population, or disappear again, or end up only being present in a certain fraction of the population. Either way, when studying a genotype, it is ''exceedingly rare'' to not arise through sexual intercourse, and impossible to spread throughout the population without it. As modern-day genetics researchers, [[Megan]] and [[Cueball]] should definitely know this fact.

Currently in the United States, topics around sex are at least partially considered taboo. This taboo most strictly covers depictions of sex and nudity in media, which are usually the domain of pornography and less mainstream art forms (e.g. nude photography). Megan defending themselves as not being “weirdos” suggests that she in fact does not want to break the taboo. In academic science however, such topics are generally part of regular scientific discussion, including depictions and descriptions that would be considered offensive in other circumstances. For example, Wikimedia Commons contains [https://commons.wikimedia.org/wiki/Category:Human_sexual_activity many depictions of sexual intercourse] for scientific and educational purposes. While some researchers, like the ones depicted in the comic, might be offended by such “lewd” contents, most would regard them well as long as they further the research on the topic at hand. Real-world biologists or geneticists would most likely not be offended by these issues, as sexual reproduction is a common or even predominant topic in both fields. Furthermore, the obscenity of the topic (genetic distributions affected by sexual reproduction) is very low in comparison to fields that deal with intercourse directly. This view seems to be shared by the off-screen commenter in the comic.

What is more problematic, and also addressed by the researcher’s comments, is the privacy of the individuals in the population under examination. Namely, using such data, it might be possible to figure out who had intercourse with whom, possibly reducing the timeframe to within less than a year based on the offspring’s age. However, since the analysis depicted likely takes place over many generations within a population, and is done on historical data, it is likely that the vast majority of the people whose genomes were analyzed are no longer alive. This is supported by the description of the population as “ancestral”. Beyond a certain point, even private data pertaining to deceased people is no longer considered sensitive, as it becomes the subject of history. The only problematic part is the ancestral information for living individuals, which is indeed worthy of protection—but not for the reasons given.

The title text alludes to the fact that most scientific papers contain a section suggesting future research avenues. This is done in the hope that other researchers will pick up where the authors have left off, or to announce the author’s own intentions for follow-up work. However, in this case, Megan and Cueball are both averse to the idea of future research, since as established they don’t think it’s appropriate to do so.

Presenting outlandish or plain bad/incorrect research has been a common topic for XKCD comics, such as in [[3129: Archaeology Research]] and [[3000: Experimental Astrophysics]].

==Transcript==
:[Cueball and Megan are shown, with Megan using a pointer stick to point at a diagram on a poster. The diagram features a top-down tree structure.]
:Megan: Our admixture analysis showed that these genotypes arose in the ancestral population almost entirely through sexual intercourse.
:Megan: Upon realizing this, we of course promptly deleted all our data.
:Off-screen voice: What? Why??
:Megan: We're not '''''weirdos!'''''
:Megan: Jeez, give these people some privacy!

{{comic discussion}}<noinclude>
[[Category:Biology]]
[[Category:Comics featuring Megan]]
[[Category:Comics featuring Cueball]]
[[Category:Sex]]

3252: Ancestral Genomes

2026-05-29T19:36:00Z

Kleinesfilmröllchen: References to other comics

{{comic
| number = 3252
| date = May 29, 2026
| title = Ancestral Genomes
| image = ancestral_genomes_2x.png
| imagesize = 299x416px
| noexpand = true
| titletext = SUGGESTIONS FOR FUTURE RESEARCH: No further research is needed as it is frankly none of our business.
}}

==Explanation==
{{incomplete|This page was created by a scientist respecting the comic’s privacy. Don't remove this notice too soon.}}

A [[wikipedia:Genotype|Genotype]] is the complete genetic makeup of an individual, i.e. all of its genes. In humans, genotypes are almost always inherited from an individual’s parents; the two parents’ genotypes combine during sexual reproduction to form the genotype of the child. Only in very rare circumstances does a genotype arise by genetic [[wikipedia:Mutation|mutation]], where parts of the DNA change randomly in a way that gives rise to a new genotype. Depending on the behavior of the mutation, it may spread throughout a population, or disappear again, or end up only being present in a certain fraction of the population. Either way, when studying a genotype, it is ''exceedingly rare'' to not arise through sexual intercourse, and impossible to spread throughout the population without it. As modern-day genetics researchers, [[Megan]] and [[Cueball]] should definitely know this fact.

Currently in the United States, topics around sex are at least partially considered taboo. This taboo most strictly covers depictions of sex and nudity in media, which are usually the domain of pornography and less mainstream art forms (e.g. nude photography). Megan defending themselves as not being “weirdos” suggests that she in fact does not want to break the taboo. In academic science however, such topics are generally part of regular scientific discussion, including depictions and descriptions that would be considered offensive in other circumstances. For example, Wikimedia Commons contains [https://commons.wikimedia.org/wiki/Category:Human_sexual_activity many depictions of sexual intercourse] for scientific and educational purposes. While some researchers, like the ones depicted in the comic, might be offended by such “lewd” contents, most would regard them well as long as they further the research on the topic at hand. Real-world biologists or geneticists would most likely not be offended by these issues, as sexual reproduction is a common or even predominant topic in both fields. Furthermore, the obscenity of the topic (genetic distributions affected by sexual reproduction) is very low in comparison to fields that deal with intercourse directly. This view seems to be shared by the off-screen commenter in the comic.

What is more problematic, and also addressed by the researcher’s comments, is the privacy of the individuals in the population under examination. Namely, using such data, it might be possible to figure out who had intercourse with whom, possibly reducing the timeframe to within less than a year based on the offspring’s age. However, since the analysis depicted likely takes place over many generations within a population, and is done on historical data, it is likely that the vast majority of the people whose genomes were analyzed are no longer alive. This is supported by the description of the population as “ancestral”. Beyond a certain point, even private data pertaining to deceased people is no longer considered sensitive, as it becomes the subject of history. The only problematic part is the ancestral information for living individuals, which is indeed worthy of protection—but not for the reasons given.

The title text alludes to the fact that most scientific papers contain a section suggesting future research avenues. This is done in the hope that other researchers will pick up where the authors have left off, or to announce the author’s own intentions for follow-up work. However, in this case, Megan and Cueball are both averse to the idea of future research, since as established they don’t think it’s appropriate to do so.

Presenting outlandish or plain bad/incorrect research has been a common topic for XKCD comics, such as in [[3129: Archaeology Research]] and [[3000: Experimental Astrophysics]].

==Transcript==
{{incomplete transcript|Don't remove this notice too soon.}}
:[Cueball and Megan are shown, with Megan using a pointer stick to point to a diagram against a wall.]
:Megan: Our admixture analysis showed that these genotypes arose in the ancestral population almost entirely through sexual intercourse.
:Megan: Upon realizing this, we of course promptly deleted all our data.
:Off-screen voice: What? Why??
:Megan: We're not '''''weirdos!'''''
:Megan: Jeez, give these people some privacy!

{{comic discussion}}<noinclude>
[[Category:Biology]]
[[Category:Comics featuring Megan]]
[[Category:Comics featuring Cueball]]
[[Category:Sex]]

3252: Ancestral Genomes

2026-05-29T19:30:42Z

Kleinesfilmröllchen: Reference the comic more

{{comic
| number = 3252
| date = May 29, 2026
| title = Ancestral Genomes
| image = ancestral_genomes_2x.png
| imagesize = 299x416px
| noexpand = true
| titletext = SUGGESTIONS FOR FUTURE RESEARCH: No further research is needed as it is frankly none of our business.
}}

==Explanation==
{{incomplete|This page was created by a scientist respecting the comic’s privacy. Don't remove this notice too soon.}}

A [[wikipedia:Genotype|Genotype]] is the complete genetic makeup of an individual, i.e. all of its genes. In humans, genotypes are almost always inherited from an individual’s parents; the two parents’ genotypes combine during sexual reproduction to form the genotype of the child. Only in very rare circumstances does a genotype arise by genetic [[wikipedia:Mutation|mutation]], where parts of the DNA change randomly in a way that gives rise to a new genotype. Depending on the behavior of the mutation, it may spread throughout a population, or disappear again, or end up only being present in a certain fraction of the population. Either way, when studying a genotype, it is ''exceedingly rare'' to not arise through sexual intercourse, and impossible to spread throughout the population without it. As modern-day genetics researchers, [[Megan]] and [[Cueball]] should definitely know this fact.

Currently in the United States, topics around sex are at least partially considered taboo. This taboo most strictly covers depictions of sex and nudity in media, which are usually the domain of pornography and less mainstream art forms (e.g. nude photography). Megan defending themselves as not being “weirdos” suggests that she in fact does not want to break the taboo. In academic science however, such topics are generally part of regular scientific discussion, including depictions and descriptions that would be considered offensive in other circumstances. For example, Wikimedia Commons contains [https://commons.wikimedia.org/wiki/Category:Human_sexual_activity many depictions of sexual intercourse] for scientific and educational purposes. While some researchers, like the ones depicted in the comic, might be offended by such “lewd” contents, most would regard them well as long as they further the research on the topic at hand. Real-world biologists or geneticists would most likely not be offended by these issues, as sexual reproduction is a common or even predominant topic in both fields. Furthermore, the obscenity of the topic (genetic distributions affected by sexual reproduction) is very low in comparison to fields that deal with intercourse directly. This view seems to be shared by the off-screen commenter in the comic.

What is more problematic, and also addressed by the researcher’s comments, is the privacy of the individuals in the population under examination. Namely, using such data, it might be possible to figure out who had intercourse with whom, possibly reducing the timeframe to within less than a year based on the offspring’s age. However, since the analysis depicted likely takes place over many generations within a population, and is done on historical data, it is likely that the vast majority of the people whose genomes were analyzed are no longer alive. This is supported by the description of the population as “ancestral”. Beyond a certain point, even private data pertaining to deceased people is no longer considered sensitive, as it becomes the subject of history. The only problematic part is the ancestral information for living individuals, which is indeed worthy of protection—but not for the reasons given.

The title text alludes to the fact that most scientific papers contain a section suggesting future research avenues. This is done in the hope that other researchers will pick up where the authors have left off, or to announce the author’s own intentions for follow-up work. However, in this case, Megan and Cueball are both averse to the idea of future research, since as established they don’t think it’s appropriate to do so.

==Transcript==
{{incomplete transcript|Don't remove this notice too soon.}}
:[Cueball and Megan are shown, with Megan using a pointer stick to point to a diagram against a wall.]
:Megan: Our admixture analysis showed that these genotypes arose in the ancestral population almost entirely through sexual intercourse.
:Megan: Upon realizing this, we of course promptly deleted all our data.
:Off-screen voice: What? Why??
:Megan: We're not '''''weirdos!'''''
:Megan: Jeez, give these people some privacy!

{{comic discussion}}<noinclude>
[[Category:Biology]]
[[Category:Comics featuring Megan]]
[[Category:Comics featuring Cueball]]
[[Category:Sex]]

3252: Ancestral Genomes

2026-05-29T19:26:52Z

Kleinesfilmröllchen: re-add character links

{{comic
| number = 3252
| date = May 29, 2026
| title = Ancestral Genomes
| image = ancestral_genomes_2x.png
| imagesize = 299x416px
| noexpand = true
| titletext = SUGGESTIONS FOR FUTURE RESEARCH: No further research is needed as it is frankly none of our business.
}}

==Explanation==
{{incomplete|This page was created by a scientist respecting the comic’s privacy. Don't remove this notice too soon.}}

A [[wikipedia:Genotype|Genotype]] is the complete genetic makeup of an individual, i.e. all of its genes. In humans, genotypes are almost always inherited from an individual’s parents; the two parents’ genotypes combine during sexual reproduction to form the genotype of the child. Only in very rare circumstances does a genotype arise by genetic [[wikipedia:Mutation|mutation]], where parts of the DNA change randomly in a way that gives rise to a new genotype. Depending on the behavior of the mutation, it may spread throughout a population, or disappear again, or end up only being present in a certain fraction of the population. Either way, when studying a genotype, it is ''exceedingly rare'' to not arise through sexual intercourse, and impossible to spread throughout the population without it. As modern-day genetics researchers, [[Megan]] and [[Cueball]] should definitely know this fact.

Currently in the United States, topics around sex are at least partially considered taboo. This taboo most strictly covers depictions of sex and nudity in media, which are usually the domain of pornography and less mainstream art forms (e.g. nude photography). In academic science however, such topics are generally part of regular scientific discussion, including depictions and descriptions that would be considered offensive in other circumstances. For example, Wikimedia Commons contains [https://commons.wikimedia.org/wiki/Category:Human_sexual_activity many depictions of sexual intercourse] for scientific and educational purposes. While some researchers, like the ones depicted in the comic, might be offended by such “lewd” contents, most would regard them well as long as they further the research on the topic at hand. Real-world biologists or geneticists would most likely not be offended by these issues, as sexual reproduction is a common or even predominant topic in both fields. Furthermore, the obscenity of the topic (genetic distributions affected by sexual reproduction) is very low in comparison to fields that deal with intercourse directly.

What is more problematic, and also addressed by the researcher’s comments, is the privacy of the individuals in the population under examination. Namely, using such data, it might be possible to figure out who had intercourse with whom, possibly reducing the timeframe to within less than a year based on the offspring’s age. However, since the analysis depicted likely takes place over many generations within a population, and is done on historical data, it is likely that the vast majority of the people whose genomes were analyzed are no longer alive. This is supported by the description of the population as “ancestral”. Beyond a certain point, even private data pertaining to deceased people is no longer considered sensitive, as it becomes the subject of history. The only problematic part is the ancestral information for living individuals, which is indeed worthy of protection—but not for the reasons given.

The title text alludes to the fact that most scientific papers contain a section suggesting future research avenues. This is done in the hope that other researchers will pick up where the authors have left off, or to announce the author’s own intentions for follow-up work. However, in this case, Megan and Cueball are both averse to the idea of future research, since as established they don’t think it’s appropriate to do so.

==Transcript==
{{incomplete transcript|Don't remove this notice too soon.}}
:[Cueball and Megan are shown, with Megan using a pointer stick to point to a diagram against a wall.]
:Megan: Our admixture analysis showed that these genotypes arose in the ancestral population almost entirely through sexual intercourse.
:Megan: Upon realizing this, we of course promptly deleted all our data.
:Off-screen voice: What? Why??
:Megan: We're not '''''weirdos!'''''
:Megan: Jeez, give these people some privacy!

{{comic discussion}}<noinclude>
[[Category:Biology]]
[[Category:Comics featuring Megan]]
[[Category:Comics featuring Cueball]]
[[Category:Sex]]

3252: Ancestral Genomes

2026-05-29T19:26:04Z

Kleinesfilmröllchen: Elaboration on the fact that genes most definitely arise/spread through sexual reproduction

{{comic
| number = 3252
| date = May 29, 2026
| title = Ancestral Genomes
| image = ancestral_genomes_2x.png
| imagesize = 299x416px
| noexpand = true
| titletext = SUGGESTIONS FOR FUTURE RESEARCH: No further research is needed as it is frankly none of our business.
}}

==Explanation==
{{incomplete|This page was created by a scientist respecting the comic’s privacy. Don't remove this notice too soon.}}

A [[wikipedia:Genotype|Genotype]] is the complete genetic makeup of an individual, i.e. all of its genes. In humans, genotypes are almost always inherited from an individual’s parents; the two parents’ genotypes combine during sexual reproduction to form the genotype of the child. Only in very rare circumstances does a genotype arise by genetic [[wikipedia:Mutation|mutation]], where parts of the DNA change randomly in a way that gives rise to a new genotype. Depending on the behavior of the mutation, it may spread throughout a population, or disappear again, or end up only being present in a certain fraction of the population. Either way, when studying a genotype, it is ''exceedingly rare'' to not arise through sexual intercourse, and impossible to spread throughout the population without it. As modern-day genetics researchers, Megan and Cueball should definitely know this fact.

Currently in the United States, topics around sex are at least partially considered taboo. This taboo most strictly covers depictions of sex and nudity in media, which are usually the domain of pornography and less mainstream art forms (e.g. nude photography). In academic science however, such topics are generally part of regular scientific discussion, including depictions and descriptions that would be considered offensive in other circumstances. For example, Wikimedia Commons contains [https://commons.wikimedia.org/wiki/Category:Human_sexual_activity many depictions of sexual intercourse] for scientific and educational purposes. While some researchers, like the ones depicted in the comic, might be offended by such “lewd” contents, most would regard them well as long as they further the research on the topic at hand. Real-world biologists or geneticists would most likely not be offended by these issues, as sexual reproduction is a common or even predominant topic in both fields. Furthermore, the obscenity of the topic (genetic distributions affected by sexual reproduction) is very low in comparison to fields that deal with intercourse directly.

What is more problematic, and also addressed by the researcher’s comments, is the privacy of the individuals in the population under examination. Namely, using such data, it might be possible to figure out who had intercourse with whom, possibly reducing the timeframe to within less than a year based on the offspring’s age. However, since the analysis depicted likely takes place over many generations within a population, and is done on historical data, it is likely that the vast majority of the people whose genomes were analyzed are no longer alive. This is supported by the description of the population as “ancestral”. Beyond a certain point, even private data pertaining to deceased people is no longer considered sensitive, as it becomes the subject of history. The only problematic part is the ancestral information for living individuals, which is indeed worthy of protection—but not for the reasons given.

The title text alludes to the fact that most scientific papers contain a section suggesting future research avenues. This is done in the hope that other researchers will pick up where the authors have left off, or to announce the author’s own intentions for follow-up work. However, in this case, Megan and Cueball are both averse to the idea of future research, since as established they don’t think it’s appropriate to do so.

==Transcript==
{{incomplete transcript|Don't remove this notice too soon.}}
:[Cueball and Megan are shown, with Megan using a pointer stick to point to a diagram against a wall.]
:Megan: Our admixture analysis showed that these genotypes arose in the ancestral population almost entirely through sexual intercourse.
:Megan: Upon realizing this, we of course promptly deleted all our data.
:Off-screen voice: What? Why??
:Megan: We're not '''''weirdos!'''''
:Megan: Jeez, give these people some privacy!

{{comic discussion}}<noinclude>
[[Category:Biology]]
[[Category:Comics featuring Megan]]
[[Category:Comics featuring Cueball]]
[[Category:Sex]]

3252: Ancestral Genomes

2026-05-29T19:09:54Z

Kleinesfilmröllchen: Improved other descriptions

{{comic
| number = 3252
| date = May 29, 2026
| title = Ancestral Genomes
| image = ancestral_genomes_2x.png
| imagesize = 299x416px
| noexpand = true
| titletext = SUGGESTIONS FOR FUTURE RESEARCH: No further research is needed as it is frankly none of our business.
}}

==Explanation==
{{incomplete|This page was created by a scientist respecting the comic’s privacy. Don't remove this notice too soon.}}
[[Megan]] and [[Cueball]] have done research on a certain genotype and present their findings. However, upon discovering the genotype is spread through sexual intercourse, they immediately deleted their data and stopped their research. This is not done for obvious or common reasons like the project being too risky, expensive or pointless to continue, but to “give the people some privacy”, and not intrude on their private life.

Currently in the United States, topics around sex are at least partially considered taboo. This taboo most strictly covers depictions of sex and nudity in media, which are usually the domain of pornography and less mainstream art forms (e.g. nude photography). In academic science however, such topics are generally part of regular scientific discussion, including depictions and descriptions that would be considered offensive in other circumstances. For example, Wikimedia Commons contains [https://commons.wikimedia.org/wiki/Category:Human_sexual_activity many depictions of sexual intercourse] for scientific and educational purposes. While some researchers, like the ones depicted in the comic, might be offended by such “lewd” contents, most would regard them well as long as they further the research on the topic at hand. Real-world biologists or geneticists would most likely not be offended by these issues, as sexual reproduction is a common or even predominant topic in both fields. Furthermore, the obscenity of the topic (genetic distributions affected by sexual reproduction) is very low in comparison to fields that deal with intercourse directly.

What is more problematic, and also addressed by the researcher’s comments, is the privacy of the individuals in the population under examination. Namely, using such data, it might be possible to figure out who had intercourse with whom, possibly reducing the timeframe to within less than a year based on the offspring’s age. However, since the analysis depicted likely takes place over many generations within a population, and is done on historical data, it is likely that the vast majority of the people whose genomes were analyzed are no longer alive. This is supported by the description of the population as “ancestral”. Beyond a certain point, even private data pertaining to deceased people is no longer considered sensitive, as it becomes the subject of history. The only problematic part is the ancestral information for living individuals, which is indeed worthy of protection—but not for the reasons given.

The title text alludes to the fact that most scientific papers contain a section suggesting future research avenues. This is done in the hope that other researchers will pick up where the authors have left off, or to announce the author’s own intentions for follow-up work. However, in this case, Megan and Cueball are both averse to the idea of future research, since as established they don’t think it’s appropriate to do so.

==Transcript==
{{incomplete transcript|Don't remove this notice too soon.}}
:[Cueball and Megan are shown, with Megan using a pointer stick to point to a diagram against a wall.]
:Megan: Our admixture analysis showed that these genotypes arose in the ancestral population almost entirely through sexual intercourse.
:Megan: Upon realizing this, we of course promptly deleted all our data.
:Off-screen voice: What? Why??
:Megan: We're not '''''weirdos!'''''
:Megan: Jeez, give these people some privacy!

{{comic discussion}}<noinclude>
[[Category:Biology]]
[[Category:Comics featuring Megan]]
[[Category:Comics featuring Cueball]]
[[Category:Sex]]

3252: Ancestral Genomes

2026-05-29T19:02:26Z

Kleinesfilmröllchen: Expand on sexual taboo and privacy implications

{{comic
| number = 3252
| date = May 29, 2026
| title = Ancestral Genomes
| image = ancestral_genomes_2x.png
| imagesize = 299x416px
| noexpand = true
| titletext = SUGGESTIONS FOR FUTURE RESEARCH: No further research is needed as it is frankly none of our business.
}}

==Explanation==
{{incomplete|This page was created by a scientist respecting the comic’s privacy. Don't remove this notice too soon.}}
In this comic, [[Megan]] and [[Cueball]] researched for a certain genotype. However, upon finding the genotype is spread through sexual intercourse, they immediately discarded their research and left the project alone - Not for obvious reasons like the project being too risky, expensive or pointless to continue, but to 'give the people some privacy', and not intrude on their private life.

Currently in the United States, topics around sex are at least partially considered taboo. This taboo most strictly covers depictions of sex and nudity in media, which are usually the domain of pornography and less mainstream art forms (e.g. nude photography). In academic science however, such topics are generally part of regular scientific discussion, including depictions and descriptions that would be considered offensive in other circumstances. For example, Wikimedia Commons contains [https://commons.wikimedia.org/wiki/Category:Human_sexual_activity many depictions of sexual intercourse] for scientific and educational purposes. While some researchers, like the ones depicted in the comic, might be offended by such “lewd” contents, most would regard them well as long as they further the research on the topic at hand. Real-world biologists or geneticists would most likely not be offended by these issues, as sexual reproduction is a common or even predominant topic in both fields. Furthermore, the obscenity of the topic (genetic distributions affected by sexual reproduction) is very low in comparison to fields that deal with intercourse directly.

What is more problematic, and also addressed by the researcher’s comments, is the privacy of the individuals in the population under examination. Namely, using such data, it might be possible to figure out who had intercourse with whom, possibly reducing the timeframe to within less than a year based on the offspring’s age. However, since the analysis depicted likely takes place over many generations within a population, and is done on historical data, it is likely that the vast majority of the people whose genomes were analyzed are no longer alive. This is supported by the description of the population as “ancestral”. Beyond a certain point, even private data pertaining to deceased people is no longer considered sensitive, as it becomes the subject of history. The only problematic part is the ancestral information for living individuals, which is indeed worthy of protection—but not for the reasons given.

The title text has more of their efforts, doing a proposal for 'future research' as to not bother, and not stick our nose in it.
==Transcript==
{{incomplete transcript|Don't remove this notice too soon.}}
:[Cueball and Megan are shown, with Megan using a pointer stick to point to a diagram against a wall.]
:Megan: Our admixture analysis showed that these genotypes arose in the ancestral population almost entirely through sexual intercourse.
:Megan: Upon realizing this, we of course promptly deleted all our data.
:Off-screen voice: What? Why??
:Megan: We're not '''''weirdos!'''''
:Megan: Jeez, give these people some privacy!

{{comic discussion}}<noinclude>
[[Category:Biology]]
[[Category:Comics featuring Megan]]
[[Category:Comics featuring Cueball]]
[[Category:Sex]]

3252: Ancestral Genomes

2026-05-29T18:40:19Z

Kleinesfilmröllchen: incomplete banner joke

221: Random Number

2026-05-28T21:02:23Z

Kleinesfilmröllchen: Clearer wording; explain that the comic contains code in the first place (not obvious to non-programmers); notes on randomness. Also hey, first edit after finally deciding to make an account here!

{{comic
| number = 221
| date = February 9, 2007
| title = Random Number
| image = random_number.png
| titletext = <nowiki>RFC 1149.5</nowiki> specifies 4 as the standard IEEE-vetted random number.
}}
==Explanation==
The comic contains computer code specifying a function (in a syntax similar to that of {{w|C (programming language)|C}}), which judging by its name should be designed to return a random number. Most functions of this form are random number ''generators'', meaning that on subsequent calls they return ''different'' random numbers. But this function just returns the ''same'' random number each time. While it could indeed have been truly randomly chosen by rolling a die as the [[156: Commented|comment]] documented, is essentially worthless were it ever to be called more than once (with the expectation of different, i.e., random, results). In other words, the results over time would not be random at all, but completely predictable and deterministic.

Alternatively, this could be seen as making fun of what many people incorrectly consider "random numbers". A mathematician will (or at least should) think about a random number as one that is independent of something (usually being independent of the next number in a list of numbers). However, the average person will often think of a list of random numbers as just "having no pattern". This difference is described in [https://simple.wikipedia.org/wiki/Hacker_koan#Uncarved_block an MIT koan]. Just to drive this point home, if the first number of a list is "4", and the second number is independent of the first, then that means the second number can also be "4" (as well as the 3rd and 4th). This obviously creates a "pattern", while still being random because of the independence. Four times "4" in a row is not a likely outcome for dice rolls, with a probability of (1/6)⁴ or approximately 0.08%. It is much more likely, for instance, to find ''at least'' one "4" among the four dice rolls (4*1/6 or 66%), or a "4" only on the first roll (1/6 or 16.7%). All three outcomes are however possible.

The {{w|IEEE}} is the organization responsible for maintaining a number of computer standards. An RFC, or {{w|Request for Comments}}, is a formal document put out to computing experts by {{w|IETF}} in the hopes of becoming a future standard. However, RFC 1149 was an {{w|April Fools' Day Request for Comments|April Fools' joke}}, [http://www.faqs.org/rfcs/rfc2549.html IP over Avian Carriers], defining how carrier pigeons can be used to transmit Internet packets. "<nowiki>RFC 1149.5</nowiki>," meanwhile, simply does not exist.

==Trivia==

* The well-known "helper website" ([http://gChq.github.io/CyberChef/#recipe=XKCD_Random_Number() CyberChef]) has a function that simulates XKCD's program.
* Esolangs.org features a [http://esolangs.org/wiki/user:XKCD_Random_Number challenge] that requires you to rewrite the program in XKCD's comic in another programming language, as either a function or a full program that prints the "4".
* Security Researchers made AMD Zen CPUs return 4 when called for randomness via a microcode [https://www.theregister.com/2025/02/04/google_amd_microcode/ update]

==Transcript==
[A computer program.]
int getRandomNumber()
{
return 4; // chosen by fair dice roll.
// guaranteed to be random.
}

{{comic discussion}}
[[Category:Programming]]
[[Category:Computers]]
[[Category:Comics with lowercase text]]