# How true is this XKCD? **URL:** \ **Category:** Factual Questions\ **Created:** [October 2, 2013, 4:34am UTC](https://boards.straightdope.com/t/how-true-is-this-xkcd/670162 "2013-10-02T04:34:11Z")\ **Posts on this page:** 18\ **Page:** 1
**Author:** ![bldysabba](https://avatars.discourse-cdn.com/v4/letter/b/ecccb3/32.png) [@bldysabba](https://boards.straightdope.com/u/bldysabba)\ **Post date:** [October 2, 2013, 4:34am UTC](https://boards.straightdope.com/t/how-true-is-this-xkcd/670162/1 "2013-10-02T04:34:11Z")
[This](http://xkcd.org/1259/) one. It refers to an orchid that is the only evidence of a once-tinct bee species. ---
**Author:** ![yorick73](https://avatars.discourse-cdn.com/v4/letter/y/b5a626/32.png) [@yorick73](https://boards.straightdope.com/u/yorick73)\ **Post date:** [October 2, 2013, 5:05am UTC](https://boards.straightdope.com/t/how-true-is-this-xkcd/670162/2 "2013-10-02T05:05:35Z")
Looks like they are stretching quite a bit: > **[A flower hints at the appearance of an extinct bee](https://whyevolutionistrue.com/2013/09/02/a-flower-hints-at-the-appearance-of-an-extinct-bee/)** > > I’ve written before about “bee-mimicking orchids,” whose petals have evolved into a shape roughly resembling that of a female bee or wasp.  Randy male hymenopterans, lured by the … ---
**Author:** ![Tabby\_Cat](https://avatars.discourse-cdn.com/v4/letter/t/6a8cbe/32.png) [@Tabby\_Cat](https://boards.straightdope.com/u/Tabby_Cat)\ **Post date:** [October 2, 2013, 5:39am UTC](https://boards.straightdope.com/t/how-true-is-this-xkcd/670162/3 "2013-10-02T05:39:48Z")
As the link notes, XKCD is stretching it only in respect of the appearance of the flower/female bee. The pollinator/flower symbiotic relationship and subsequent extinction (and evolution) appears to have actually happened. ---
**Author:** ![Reply](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/reply/32/15952_2.png) [@Reply](https://boards.straightdope.com/u/Reply)\ **Post date:** [October 2, 2013, 6:29am UTC](https://boards.straightdope.com/t/how-true-is-this-xkcd/670162/4 "2013-10-02T06:29:49Z")
Maybe the bee wouldn’t have gone extinct if it didn’t waste all its reproductive energy spreading pollen for the dastardly mimic orchid. Karma’s a bitch, huh? ---
**Author:** ![AaronX](https://avatars.discourse-cdn.com/v4/letter/a/7bcc69/32.png) [@AaronX](https://boards.straightdope.com/u/AaronX)\ **Post date:** [October 2, 2013, 12:24pm UTC](https://boards.straightdope.com/t/how-true-is-this-xkcd/670162/5 "2013-10-02T12:24:49Z")
Speaking of truth, is asexual reproduction “a last-ditch genetic strategy that only delays the inevitable”? I thought we still hadn’t figured out a good reason for sexual reproduction. ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [October 2, 2013, 12:31pm UTC](https://boards.straightdope.com/t/how-true-is-this-xkcd/670162/6 "2013-10-02T12:31:21Z")
> [@AaronX](#): > > Speaking of truth, is asexual reproduction “a last-ditch genetic strategy that only delays the inevitable”? I thought we still hadn’t figured out a good reason for sexual reproduction. Self-pollination is not asexual reproduction. I imagine it’s hard to say if it’s a ‘last ditch’ effort - it’s not as though plants ever know that they are in danger of extinction. Self-pollination and asexual reproduction methods such as budding or suckering do confer survival advantages to some (otherwise sexually-reproducing) organisms in some contexts. ---
**Author:** ![Learjeff](https://avatars.discourse-cdn.com/v4/letter/l/94ad74/32.png) [@Learjeff](https://boards.straightdope.com/u/Learjeff)\ **Post date:** [October 2, 2013, 2:08pm UTC](https://boards.straightdope.com/t/how-true-is-this-xkcd/670162/7 "2013-10-02T14:08:53Z")
> [@AaronX](#): > > Speaking of truth, is asexual reproduction “a last-ditch genetic strategy that only delays the inevitable”? I thought we still hadn’t figured out a good reason for sexual reproduction. For a nice hypothesis and a lot of other interesting tidbits, read “Power, Sex, and Suicide” by Nick Lane. According to Lane, mitochondria have their own DNA, but only the minimal set that’s required to regulate the functioning of an individual mitochondrial unit. To function, the M requires precursors built from nuclear DNA that are compatible with the MDNA. Reproduction using pre-sexual methods would provide incompatible DNA, reducing success rates for offspring. A strategy to mitigate this is to have one parent provide the mitochondria. If the nuclear DNA is incompatible, the embryo is nonviable, but a majority would be viable. After writing that, I see plenty of holes, so no doubt I’m missing important bits. Lane goes on to say that the formation of eukaryotes from archea and the mitochondrial precursor (probably bacteria) was extremely unlikely – he hazards the guess that it’s less likely than biotic origin (which happend pretty quickly once the Earth cooled down). I don’t remember how the advent of nucleation fit in but he discussed that a lot too. Forgive the tangent. ---
**Author:** ![Learjeff](https://avatars.discourse-cdn.com/v4/letter/l/94ad74/32.png) [@Learjeff](https://boards.straightdope.com/u/Learjeff)\ **Post date:** [October 2, 2013, 2:21pm UTC](https://boards.straightdope.com/t/how-true-is-this-xkcd/670162/8 "2013-10-02T14:21:50Z")
The use of the term “last ditch effort” is poetic and gets across the point, but definitely anthropomorphic (as we often see when talking about what “Nature” or “Evolution” does, much to the delight of deniers who try to turn them into what they’re not.) Still, self-pollination is a less optimal solution that results from an otherwise evolutionary dead end, and being less optimal, the species is less likely to survive a shift in its evolutionary niche. That is, it would take a smaller shift to kill it off than if it was reproducing sexually. While there are a lot of questions about the origins of sexual reproduction, once a species goes down that path it’s difficult to abandon it as a means of exchanging DNA with other members of the species. (This is in contrast to asexual reproduction merely to proliferate nearly the same set of DNA.) Self-pollination serves the purpose of producing new combinations of alleles (that is, for any gene where the original has two different alleles, the offspring have 3 possibilities, with 25%, 50% and 25% probabilities). This recombination can help optimize the original genome, but it eliminates the possibility of combining two beneficial novelties arising in different individuals. So, while there are many mysteries about the advantages of sexual reproduction versus the kind of plasmid-swapping that bacteria do (… sometimes, with “sexes” …), there’s no mystery here about self-pollination being less effective than cross-pollination. ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [October 2, 2013, 3:45pm UTC](https://boards.straightdope.com/t/how-true-is-this-xkcd/670162/9 "2013-10-02T15:45:21Z")
I wouldn’t call the XKCD strip a stretch at all. Part of the point of the strip is that it _isn’t_ a very faithful depiction of the bee. It’s a depiction of how the female bee looks _to a male bee_, as _interpreted by a plant_. It’s just that that third-hand depiction is the best we have for that bee. ---
**Author:** ![Alan\_Smithee](https://avatars.discourse-cdn.com/v4/letter/a/2acd7d/32.png) [@Alan\_Smithee](https://boards.straightdope.com/u/Alan_Smithee)\ **Post date:** [October 3, 2013, 1:18am UTC](https://boards.straightdope.com/t/how-true-is-this-xkcd/670162/10 "2013-10-03T01:18:46Z")
I agree that that’s the point of the strip, **Chronos** , but the real question, per **yorick73** ’s link, is whether the story of an extinct bee is true at all, or whether the self-pollination is actually an adaptation that allows the flower to exist far north of its pollinator _Eucera_. I haven’t been able to tell if Randall’s story is even plausible, much less likely, or where he got it from. Does anyone have any information on the answer to that question? ---
**Author:** ![Colibri](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/colibri/32/1841_2.png) [@Colibri](https://boards.straightdope.com/u/Colibri)\ **Post date:** [October 3, 2013, 2:05am UTC](https://boards.straightdope.com/t/how-true-is-this-xkcd/670162/11 "2013-10-03T02:05:02Z")
> [@Tabby\_Cat](#): > > As the link notes, XKCD is stretching it only in respect of the appearance of the flower/female bee. The pollinator/flower symbiotic relationship and subsequent extinction (and evolution) appears to have actually happened. However, as the link indicates, the pollinator _is not extinct_. Plants in the southern part of the orchid’s range are pollinated by the bee _Eucera longicornis_, in which males attempt to copulate with the flower, and other bees which are attracted by scent (which may mimic that of a female bee). One might hypothesize that the bee once occurred in the northern part of the orchid’s range, but later became locally extinct there; or, more likely, that the orchid has spread northward beyond the range of the bee (perhaps after being wiped out by the Ice Ages). In either case, it has used its capability to self pollinate to persist or spread in the absence of its original main pollinator. It’s a nice story, but I’m not seeing any evidence that the flower mimics an extinct bee. ---
**Author:** ![bldysabba](https://avatars.discourse-cdn.com/v4/letter/b/ecccb3/32.png) [@bldysabba](https://boards.straightdope.com/u/bldysabba)\ **Post date:** [October 3, 2013, 2:12am UTC](https://boards.straightdope.com/t/how-true-is-this-xkcd/670162/12 "2013-10-03T02:12:22Z")
> [@Colibri](#): > > It’s a nice story, but I’m not seeing any evidence that the flower mimics an extinct bee. Just to clarify, this is what I was asking. I mean, if the flower’s our only evidence of the now extinct bee, as the comic strip implies, that doesn’t make a very strong case. ---
**Author:** ![ZenBeam](https://avatars.discourse-cdn.com/v4/letter/z/3ab097/32.png) [@ZenBeam](https://boards.straightdope.com/u/ZenBeam)\ **Post date:** [October 3, 2013, 2:21am UTC](https://boards.straightdope.com/t/how-true-is-this-xkcd/670162/13 "2013-10-03T02:21:45Z")
If you have a flower which self-pollinates as this one does (at least in the Northern range), wouldn’t it occasionally cross-pollinate due to other insects landing on one, then landing on another one by chance? So I’d expect it would still have some small level of gene flow. ---
**Author:** ![Colibri](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/colibri/32/1841_2.png) [@Colibri](https://boards.straightdope.com/u/Colibri)\ **Post date:** [October 3, 2013, 2:32am UTC](https://boards.straightdope.com/t/how-true-is-this-xkcd/670162/14 "2013-10-03T02:32:03Z")
> [@ZenBeam](#): > > If you have a flower which self-pollinates as this one does (at least in the Northern range), wouldn’t it occasionally cross-pollinate due to other insects landing on one, then landing on another one by chance? So I’d expect it would still have some small level of gene flow. Some sites indicate that other species of bee pollinate it at least occasionally where the main pollinator is absent. One stated that the orchid has a number of variants, which is what would be expected if it was not under strong selection to maintain its resemblance to a female bee. ---
**Author:** ![Tabby\_Cat](https://avatars.discourse-cdn.com/v4/letter/t/6a8cbe/32.png) [@Tabby\_Cat](https://boards.straightdope.com/u/Tabby_Cat)\ **Post date:** [October 3, 2013, 3:04am UTC](https://boards.straightdope.com/t/how-true-is-this-xkcd/670162/15 "2013-10-03T03:04:11Z")
> [@Colibri](#): > > However, as the link indicates, the pollinator _is not extinct_. Plants in the southern part of the orchid’s range are pollinated by the bee _Eucera longicornis_, in which males attempt to copulate with the flower, and other bees which are attracted by scent (which may mimic that of a female bee). This is in question. XKCD posits that the northern variant was not polinated by Eucera, but some other bee (or insect), and this is reflected in the paragraph from the link: > [@](#): > > The flowers have a generalized shape, and I’m not sure whether individuals of O. apifera in southern Europe, where they mimic an extant insect, differ in appearance from those in the northern part of the range, where they’re self-pollinated and supposedly resemble a “ghost insect.” If they don’t differ, then we can’t say, as the cartoon does, that the shape of flowers in, say, England tells us something about the appearance of the extinct pollinator. There must be work on this, but I don’t know of it. I am even less equipped than the author of the link at performing independent research into this, so I’ll have to take someone’s word for it. Randall (author of XKCD) has been rather good with his research so far, so I’m not dismissing his statement out of hand. ---
**Author:** ![Alan\_Smithee](https://avatars.discourse-cdn.com/v4/letter/a/2acd7d/32.png) [@Alan\_Smithee](https://boards.straightdope.com/u/Alan_Smithee)\ **Post date:** [October 3, 2013, 3:07am UTC](https://boards.straightdope.com/t/how-true-is-this-xkcd/670162/16 "2013-10-03T03:07:49Z")
> [@bldysabba](#): > > Just to clarify, this is what I was asking. I mean, if the flower’s our only evidence of the now extinct bee, as the comic strip implies, that doesn’t make a very strong case. ISTM that it could be a strong case, if the orchid wasn’t being cross-pollinated anywhere in its current range. It clearly evolved to mimic some insect. But the fact that it is currently being cross-pollinated by a bee in the Mediterranean region prompts the question of whether it evolved to attract a now extinct bee in northern Europe and is attracting _E. longicornis_ only in the absence of its original pollinator, or if _E. longicornis_ is the original pollinator and either the bee’s range has shifted or the orchid’s range has expanded beyond the pollinator’s. In the absence of any other evidence, the last seems most likely to this non-scientist. ---
**Author:** ![Colibri](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/colibri/32/1841_2.png) [@Colibri](https://boards.straightdope.com/u/Colibri)\ **Post date:** [October 3, 2013, 3:43am UTC](https://boards.straightdope.com/t/how-true-is-this-xkcd/670162/17 "2013-10-03T03:43:50Z")
> [@Tabby\_Cat](#): > > I am even less equipped than the author of the link at performing independent research into this, so I’ll have to take someone’s word for it. Randall (author of XKCD) has been rather good with his research so far, so I’m not dismissing his statement out of hand. I’m finding no corroboration in the technical literature of the idea. In fact, in the snippet [here,](http://books.google.com/books?id=5YDwAAAAMAAJ&q=ophrys+apifera+eucera+heinrich+extinct&dq=ophrys+apifera+eucera+heinrich+extinct&hl=en&sa=X&ei=e-ZMUtvSDIP68QSzvYCYDQ&ved=0CC0Q6AEwAA) the extinction idea is attributed to an hypothesis by bee researcher Bernd Heinrich that was disproved by Kullenberg in 1973. To the best I can determine there is no evidence to support the idea that the shape of the orchid is due to an extinct pollinator. ---
**Author:** ![Alan\_Smithee](https://avatars.discourse-cdn.com/v4/letter/a/2acd7d/32.png) [@Alan\_Smithee](https://boards.straightdope.com/u/Alan_Smithee)\ **Post date:** [October 3, 2013, 3:56am UTC](https://boards.straightdope.com/t/how-true-is-this-xkcd/670162/18 "2013-10-03T03:56:24Z")
Stupid facts, always taking the beauty out of everything!