[HN Gopher] First confirmed hatchings of two California condor c...
___________________________________________________________________
First confirmed hatchings of two California condor chicks from
unfertilized eggs
Author : dsr12
Score : 162 points
Date : 2021-10-30 07:32 UTC (2 days ago)
(HTM) web link (stories.sandiegozoo.org)
(TXT) w3m dump (stories.sandiegozoo.org)
| DocFeind wrote:
| I can't explain how stoked I am about this, I was in SanDiego
| when they were on the verge of extinction, even got the chance to
| go behind the scenes for the original breeding program. Knowing
| nature refuses to let them fade away even without our
| intervention is epicly awesome news.
| darkwizard42 wrote:
| If you have a chance, check out the breeding program at The
| Peregrine Fund near Boise, ID. We were able to stop there on a
| road trip and it was really remarkable how many breeding pairs
| they have. As a fan of birds of prey they also have several
| eagle and hawk varieties and breed a significant number of
| Peregrine falcons as well!
|
| https://www.peregrinefund.org/visit
| penneyd wrote:
| Unfortunately both of the condors did have some documented
| health issues. SB260, a male hatched at the San Diego Zoo
| Safari Park in 2001, died two years later after being released
| into the wild--he was always small and did not integrate well
| with the wild birds. SB517, a male hatched at Los Angeles Zoo
| in 2009, had a curved spine and trouble walking. He was never
| released into the wild and died in captivity at about age
| eight.
|
| https://www.theatlantic.com/science/archive/2021/10/californ...
| sharmin123 wrote:
| Are There Top Signs of a Cheating Lover? What To do Then?:
| https://www.hackerslist.co/are-there-top-signs-of-a-cheating...
| irrational wrote:
| Hmm, all birds are dinosaurs. It's been a long time since I last
| saw Jurassic Park, but wasn't something like this a plot line in
| the film?
| simiones wrote:
| The plotline there, as far as I remember, was that bullfrog DNA
| meant that some female dinosaurs could actually morph to become
| male and reproduce with the females (this is something that
| happens in some fish, amphibians, and even reptiles, where sex
| is not genetically determined).
| wil421 wrote:
| Grouper are all born females but they have both male/female
| organs at birth. The largest females will turn into males.
| AutumnCurtain wrote:
| Correct, and they had a designed lysine deficiency that was
| supposed to make them reliant on human-given dietary
| supplements to live. By consuming lysine-rich foods they were
| able to live without humans and some gradually changed sex to
| become male, leading to viable reproductive groups on the
| island.
| Dangeranger wrote:
| Yes, it is exactly this plot line for how the dinosaurs were
| able to reproduce. All the animals were selected to be female
| to prevent natural reproduction.
| iammiles wrote:
| There is, but if I remember correctly this was due to using
| frog DNA to fill in missing DNA gaps.
| handrous wrote:
| Same explanation's used in the novel, too.
| libria wrote:
| Somewhat. In both cases, females were able to self-reproduce.
| In the film, females switched to male to fertilize. In the
| condors case, eggs developed without fertilization from males
| who were available.
| dang wrote:
| Recent and related:
|
| _The first report of asexual reproduction in California condors_
| - https://news.ycombinator.com/item?id=29050435 - Oct 2021 (16
| comments)
| bencollier49 wrote:
| So in birds, sex chromosome arrangement is a reverse of what we
| have in humans. Their males are ZZ and the female is ZW. Which is
| why only males appear from this parthenogenesis.
| rory wrote:
| > _Which is why only males appear from this parthenogenesis_
|
| Could you explain the mechanism? If the female has both
| chromosomes, why couldn't it produce offspring with both?
| smiley1437 wrote:
| The mostly likely path to parthenogenesis in a ZW female is
| making ZZ and WW offspring, and the WW is usually not viable.
|
| https://en.wikipedia.org/wiki/Parthenogenesis#Sex_of_the_off.
| ..
| semenko wrote:
| The mechanisms of parthonenogensis aren't fully
| characterized, but at a high level, it occurs in a secondary
| oocyte during meiosis II -- the oocyte only starts out with a
| Z or W chromosome.
|
| It's perhaps best shown in this figure: https://rep.bioscient
| ifica.com/view/journals/rep/155/6/image...
|
| (Via this paper: https://pubmed.ncbi.nlm.nih.gov/29559496/)
| dredmorbius wrote:
| Right.
|
| From my very shallow understanding:
|
| - The fact that females are defined by unmatched sex
| chromosomes rather than matched ones means that in haploid
| parthenogenesis (a split and rejoining of a single half of a
| genome, rather than fertilisation by male and female sex
| cells), the resultant sex cells are _either_ ZZ (vialble male)
| _or_ WW (nonviable "super-female").
|
| - Parthenogenesis in mammals on a similar basis isn't possible
| as the umatched chromsome is found in males (giving a viable XX
| female) ... but without an ovum or womb. A self-replicating
| female egg would be XX.[1] There's ... some research into
| parthenogenesis in mammals, and at least one apparent observed
| instance.[2]
|
| - In the case of Avian or similarly Z/W species, _parthogenesis
| is a potentially viable option for resuming sexual reproduction
| of a population in which all males have been lost_. For
| mammallian populations, not so much. In any case, there 'd
| likely be an extreme genetic bottleneck.
|
| ________________________________
|
| Notes:
|
| 1. Religious implications for spontaneous mammalian
| parthogenesis resulting in male offspring are left ...
| undiscussed.
|
| 2. See Google Scholar for a literature overview:
| https://scholar.google.com/scholar?hl=en&as_sdt=7%2C39&q=par...
| s1artibartfast wrote:
| If the females are ZW, why can't they make WW or ZW?
| simiones wrote:
| ZW is less likely because normally parthenogenesis starts
| with a haploid egg cell (Z or W) that undergoes meiosis
| alone, copying its own chromosomes - becoming ZZ if it
| started as Z and WW if it started as W. WW is normally not
| viable, just like YY in mammals, so the most likely case of
| parthenogenesis by far is ZZ, male.
| s1artibartfast wrote:
| Thank you!
| guerreroguy wrote:
| That's nuts
| HenryKissinger wrote:
| _Condors. Condors are on the verge of extinction. If I was to
| create a flock of condors on this island, you wouldn 't have
| anything to say._
|
| Also:
|
| > However, in a surprising twist, they found that neither bird
| was genetically related to a male--meaning both chicks were
| biologically fatherless; and accounted for the first two
| instances of asexual reproduction, or parthenogenesis, to be
| confirmed in the California condor species.
|
| Life, uh, finds a way.
| cromwellian wrote:
| Damn, you beat me to it. :)
| dmead wrote:
| well, there it is.
| dredmorbius wrote:
| For those thinking "Dupe", this specific submission seems to have
| hit the 2nd chance queue, as the item was submitted 2 days ago.
| Meaning it's _not_ actually a duplicate.
|
| Algolia shows the original submission date, at least for now:
|
| https://hn.algolia.com/?dateRange=pastMonth&page=0&prefix=fa...
| nitrogen wrote:
| It appears there was a related story though:
| https://news.ycombinator.com/item?id=29070133
| dredmorbius wrote:
| I tend to discount discussions below a certain threshold.
|
| (What threshold is hard to say, though probably in the 20--40
| range. Of course, interesting and salient comments can occur
| at any level. Perhaps more concentrated in smaller
| discussions.)
| bicx wrote:
| Quite the insult to the male condors. They were housed with the
| females, and but the females biologically opted for cloning
| themselves instead.
| adolph wrote:
| _[Condorman] did poorly at the box office. Disney reportedly
| lost $9.5 million on the picture. The disappointing financial
| returns from Condorman, along with three other flop films,
| contributed to Disney 's poor financial performance in 1981._
|
| https://en.wikipedia.org/wiki/Condorman
| the_af wrote:
| Aside for the title "Condorman", how is this movie relevant
| for the article we are discussing?
| lainga wrote:
| Male clones of themselves even!
| HenryKissinger wrote:
| 200 000 units are ready, with a million more well on their
| way.
| voz_ wrote:
| Please no low effort memes.
| nindalf wrote:
| We don't do that here.
| fijiaarone wrote:
| There's a perfectly logical, very probable, quite natural
| explanation, but the "researchers" claiming that their
| impossible, ridiculous, unfounded explanation can't possibly be
| wrong because..."muh politics"
| rhernandez35 wrote:
| What are you trying to say?
| simiones wrote:
| Is condor parthenogenesis a major political issue in the United
| States?
| Razengan wrote:
| Everything is a major political issue in the United States.
| the_af wrote:
| I don't see anything political or absurd in this article, what
| do you mean?
| Dangeranger wrote:
| Instead of posting a hyperbolic comment, how about you describe
| what the "perfectly logical, very probable, quite natural
| explanation" is.
| rsynnott wrote:
| I assume your logical probable natural explanation is that
| another male condor visited? This probably isn't as logical or
| probable as you think; they're critically endangered and all
| known examples would be DNA sequenced. Parthenogenesis is known
| to happen occasionally in birds, so it doesn't really seem all
| that out-there.
|
| > impossible, ridiculous, unfounded explanation
|
| ... What makes you think it's any of these?
|
| > can't possibly be wrong because..."muh politics"
|
| I may just be out of date, but I hadn't realised that the
| reproductive habits of condors had been particularly
| politicised.
| LadyCailin wrote:
| Life uh.. finds a way.
| voz_ wrote:
| I was reading the wikipedia article, and this line "Use of an
| electrical or chemical stimulus can produce the beginning of the
| process of parthenogenesis in the asexual development of viable
| offspring.[97]"
|
| Really stood out to me. It seems like there are stimuli that can
| trigger this process (either naturally or induced).
|
| I wonder if learning about those pathways/approaches/(APIs?) can
| unlock manual triggering of other behaviors (like telling an
| Immune system to calm down during allergies / cytokine storm, or
| spurring or stopping growth of certain cells...)
| BurningFrog wrote:
| So this is essentially Condors cloning themselves.
| HenryKissinger wrote:
| How does it work? I don't know how condors regulate their
| internal functions. As a human, I can control my muscles and my
| breathing, but I can't control, say, my digestion, my liver, my
| heart beat (except indirectly by either relaxing or doing
| stressful activities). How would a bird "flip the switch" and
| initiate asexual reproduction?
| mavhc wrote:
| Lack of chemicals from the male to inhibit the process
| probably
| simiones wrote:
| Interestingly, in this case males were in fact available -
| it just seems based on genetic studies that they didn't
| participate in these particular chicks (the mothers went on
| to have other chicks through normal reproduction).
| namanyayg wrote:
| How can anyone answer a question about the subjective
| experience of a bird? :)
|
| If I had to guess, it could be a subconscious switch
| happening based on environmental and mood factors, similiar
| to how human pregnancies can miscarry in times of extreme
| stress.
| the_af wrote:
| I don't know the answers to your questions, but
| parthenogenesis is confirmed to happen in other organisms. So
| I presume it could follow an analogous mechanism with
| condors.
| boomboomsubban wrote:
| Do condors generally have one egg at a time or were there other
| eggs hatched at the same time with a male parent? Do they think
| the two bird's early deaths were related to their
| parthenogenesis, and did the 8 year old one parent any children?
| On that note, what was the gender of the unfertilized chicks?
| jaqalopes wrote:
| Apologies for the low-effort comment, but this really freaks me
| out. I had no idea birds could reproduce asexually! That's crazy!
|
| Feels like an unanswerable question, but: could we ever see
| something like this in mammals? A virgin birth, for lack of a
| better phrase?
| dnautics wrote:
| > could we ever
|
| "ever" is pretty open-ended. In principle, it's possible.
|
| The most obvious problem is that if the maternal genes include
| any that are homozygous lethal or homozygous impaired, the
| embryo is also a no-go. This is _in principle_ fixable using
| genetic editing using known techniques.
|
| The more subtle biggest obstacles that I can think of of the
| top of my head is DNA methylation-related defects. If you are
| interested in a "quick soundbite example" of why this is
| important, I recommend reading
| https://en.wikipedia.org/wiki/Prader%E2%80%93Willi_syndrome
| (note the 25% of cases when this is what happens when there are
| by bad luck two maternal copies - and zero paternal copies - of
| ONE chromosome, similarly Angelman's syndrome); all chromosomes
| -- or any other chromosome, it appears -- is embryonic lethal
| in humans.
|
| The underlying mechanism is:
| https://en.wikipedia.org/wiki/Genomic_imprinting
|
| There is not any known way to effectively edit DNA methylation.
| It doesn't take star-trek level phlebotonium to get there (it's
| physically possible, just not with current levels of tech).
| simiones wrote:
| According to wikipedia, it does occasionally happen that a
| human egg cell undergoes parthenogenesis and starts developing,
| but as far as has been recorded, the fetus is never viable and
| is usually regarded as a type of tumor called a teratoma;
| occasionally, this does lead to some fetus-like shape of the
| tumor, in which case it is known as a fetiform teratoma.
|
| Interestingly, there are a handful of cases of functioning
| human individuals who have cell lines in their body that are
| the result of parthenogenesis: an egg cell starts dividing by
| itself, and is fertilized only after this process has started.
| Next, the feritilized cell line develops normally, while the
| unfertilized cell line keeps developing as well but in limited
| ways - in the first known case, the white blood cells of a boy
| were found to be entirely derived from his mother, while other
| cell lines were normal XY cells inherited from both parents.
|
| https://en.wikipedia.org/wiki/Parthenogenesis#Humans
| simiones wrote:
| Also found a medical article describing a clinical case and
| also making the parthenogenesis link.
|
| Caution when clicking, the article also contains some photos
| of the teratoma, which are slightly disturbing!
|
| https://meridian.allenpress.com/aplm/article/130/10/1552/459.
| ..
| MisterTea wrote:
| It's been proposed that artificial sperm could be fashioned
| from a woman's DNA. I suppose a child born from both a mothers
| egg and "sperm" could be considered a self made clone.
| pippy wrote:
| There's a great passage about this in Genome by Matt Ridley,
| which is a great book for anyone interested. In mammals both
| the male and female gametes imprint their DNA in their sex
| cells to repress certain genes, if you combine two generic
| sequences from two males (with no modification) the zygote
| forms with no brain and too much placenta and dies soon after.
| If you do the reverse with females, you wind up with a
| oversized head and no placenta. The working theory is embryonic
| development is a competitive environment, where males want the
| best for their offspring at the expense of the female host, and
| the females 'fight' back by limiting the amount of resources
| the child has. it's only been recently we've had the technology
| to remove the epigenetic markers from DNA sequences to allow
| combinations of same sex strands.
| inside65 wrote:
| Many would argue this already occurred with Jesus, born from
| the virgin Mary.
| brudgers wrote:
| _Many would argue_
|
| Paul's Letter to the Internetans: Chapter 1, Verse 1.
| the_af wrote:
| Paul's Letter contains this warning: "[And Thou Shalt Add a
| Citation, Lest Your Claim Be Purged From Internetan
| Records]"
| simiones wrote:
| Most Christians believe that that was not some biological
| process, but a true miracle where God himself bestowed this
| child on Mary. It would be technically correct that this was
| parthenogenesis, but it is a completely different...
| mechanism.
|
| Most non-Christians, even if they believe Jesus was a true
| historical figure, do not believe that his mother was a
| virgin.
| mistrial9 wrote:
| this is complicated, nuanced and not literal; it is a
| typical thing for critics to latch on to, so let's be wise-
| cautious with the exposition here at YNews, please
| xxpor wrote:
| Not Christian, but as my Rabbi used to say: "When God
| created the earth 5782 years ago (give or take a few
| billion years),"
| mistrial9 wrote:
| Mel Brooks?
| xxpor wrote:
| It would not shock me in the slightest if that's where he
| got it.
| yupper32 wrote:
| Miracles are absolutely (supposed to be) literal. It's a
| requirement for Sainthood, for example.
| anunnymouse wrote:
| 'this is complicated, nuanced and not literal' - arn't
| most things though? At least the person you are replying
| to started their comment with a weasel word - you're the
| one making the categorical statement about whether it is
| literal.
| Razengan wrote:
| > _be wise-cautious with the exposition here at YNews,
| please_
|
| One would think that YNews would be the most appropriate
| place for questioning blind faith in absurd claims.
| simiones wrote:
| Absolutely. I wasn't trying to criticize anyone's
| beliefs, and I hope I didn't come across as such, and
| sincerely apologize if it did.
|
| My only point was exactly that it's not a great idea to
| take a religious experience and analyze it as an example
| of a basic biological phenomenon.
| hadlock wrote:
| > Most Christians believe that
|
| Do you have any sort of statistics to back this up? A
| survey of some kind? From my own experience, most people
| who are Christian subscribe to the lifestyle and teachings,
| but do not accept 100% of the bible as truth.
| the_af wrote:
| > _Do you have any sort of statistics to back this up? A
| survey of some kind?_
|
| The virgin birth of Jesus is an article of faith and
| dogma for Catholicism, itself a major branch of
| Christianity.
| freeflight wrote:
| How about the fact that over a billion people are members
| of the Catholic Church? The membership of which requires
| believing quite a bit of Biblical literalism.
|
| Tbh that whole argument is always kinda weird: If those
| people don't believe in the whole thing, why are they
| members in a church about it? That's pretty much the only
| statistic you need.
|
| [0] https://www.bbc.com/news/world-21443313
| blendergeek wrote:
| I don't have data for the whole world, but at least in
| the USA, most Christians (and the majority of Americans)
| believe in the virgin birth of Jesus Christ [0].
|
| [0] https://www.pewforum.org/2017/12/12/americans-say-
| religious-...
| handrous wrote:
| It's... at least the official doctrine of most Christian
| churches, yeah, and that's usually held as a particularly
| important point. Catholics, certainly, and they're rather
| numerous. It is possible that many, or even most,
| Christians disagree with tenets of faith that their
| churches hold to be absolutely vital and indispensable, I
| suppose.
|
| [EDIT] It's part of the Nicene Creed, even. I think it's
| fair to say that if most church-goers at most Christian
| churches told a priest or pastor that they didn't believe
| that God miracle'd a baby into the Virgin Mary, it would,
| at the very least, give the priest or pastor a frowny
| face and/or evoke a "wait... what exactly do you think
| we're up to, here?" reaction.
| Falling3 wrote:
| Anecdotal, but I've never met or even heard of a
| Christian who believed in the virgin birth but thought it
| was the result of a natural process. Are there any
| examples of that you're aware of?
| Apocryphon wrote:
| There was a Discovery channel documentary in the 2000s
| that tried to give "scientific" explanations for the
| miracles in Christ's life. Parthenogenesis was the theory
| they advanced instead of divine conception.
| dragonwriter wrote:
| > Most Christians believe that that was not some biological
| process, but a true miracle where God himself bestowed this
| child on Mary.
|
| Most Christians that have spent the time to consider what
| it means for God to manifest a miracle fairly explicitly
| accept that that necessarily involves some physical
| sequence of events, potentially leveraging underlying
| capacities which in time and space predate the event which
| God, being all-knowing and existing outside of time and
| space, may have created for the express purpose of that
| specific miracle.
|
| And most of the rest of Christians would probably dismiss
| the mechanical question as irrelevant for miracles,
| preferring to ask "why" rather than "how".
| the_af wrote:
| > _Most Christians that have spent the time to consider
| what it means for God to manifest a miracle fairly
| explicitly accept that that necessarily involves some
| physical sequence of events_
|
| That hasn't been my experience. I don't know about "most"
| Christians -- I wouldn't dare presume to speak for anyone
| in the US, for example -- but every Catholic I've spoken
| with (I live in a majorly Catholic country) believes in
| the entirely miraculous virgin birth of Jesus.
|
| I think the phrasing "most Christians that have spent the
| time to consider [...]" is unfortunate; it reads like
| "every Christian which believes [this thing] believes
| [this thing]". Or it makes Christians who do believe in
| the miraculous birth without a prior physical setup to be
| somehow less thinking Christians.
|
| Do note I'm an atheist myself so I certainly don't
| believe in miracles, either direct or indirect; I've no
| dog in this race.
| dragonwriter wrote:
| > but every Catholic I've spoken with (I live in a
| majorly Catholic country) believes in the entirely
| miraculous virgin birth of Jesus.
|
| Sure. I'm a Catholic and _I_ believe that.
|
| It's also a non-explanation that doesn't actually rule
| out any particular physical process occurring as part of
| the manifestation of the miracle.
|
| Other than things like the routine transubstantiation of
| the elements of the eucharist, where a _defined part of
| the miracle is the absence of any physical manifestation
| of it occurring_ [0], that 's pretty typical of miracles.
|
| [0] Why doesn't the bread and wine that miraculously
| becomes the body and blood of Christ taste like flesh and
| blood? Well, because it miraculously also retains all the
| physical properties of bread and wine...
| mistrial9 wrote:
| lots of stories in religion are not literal -- they are
| presented as undeniable Truth to quash low-level arguements
| rsynnott wrote:
| I mean, I'm not sure that _many_ would argue that. Most
| people would either take the view that Jesus had a human
| father, or that a miracle was involved. If nothing else, if
| he'd come about by this pathway, he'd be XX, which you'd
| think would have merited a mention in the Bible.
|
| (It isn't totally unknown for XX people to be phenotypically
| male, and it'd fit with him having no kids, but really this
| seems like a needlessly complicated backstory for Jesus.)
| thaumasiotes wrote:
| > Feels like an unanswerable question, but: could we ever see
| something like this in mammals? A virgin birth, for lack of a
| better phrase?
|
| The question is easy to answer. Yes, this is a development that
| shows up from time to time. Species displaying _only_ asexual
| reproduction all tend to be evolutionarily young, which implies
| that adopting the strategy rapidly leads to extinction, but it
| has short-term benefits which mean that there 's usually
| something around trying it out. (And then there are species
| with obligatory parthenogenesis and also obligatory sexual
| reproduction, like aphids, which don't experience the problems
| that pure-cloning species do.)
|
| By way of examples of sexually-reproducing species shifting to
| parthenogenesis, there is a species of lizard that can only
| reproduce that way. We can be certain they originally
| reproduced sexually since they still engage in a (pointless)
| simulation of copulation.
| hristov wrote:
| I think it is far more likely the researchers screwed up here.
| lmkg wrote:
| Parthenogenesis is more common in the animal kingdom than you
| might expect.
| Symmetry wrote:
| At least part time parthenogenesis. Eukaryotic species
| sometimes go all in on asexual reproduction but almost always
| die out in a few million years due to not being able to
| evolve along with changing conditions.
| penneyd wrote:
| This article has a bit more detail and describes the health
| issues these birds experienced
|
| https://www.theatlantic.com/science/archive/2021/10/californ...
|
| "both of the condors did have some documented health issues.
| SB260, a male hatched at the San Diego Zoo Safari Park in 2001,
| died two years later after being released into the wild--he was
| always small and did not integrate well with the wild birds.
| SB517, a male hatched at Los Angeles Zoo in 2009, had a curved
| spine and trouble walking. He was never released into the wild
| and died in captivity at about age eight."
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(page generated 2021-11-01 23:01 UTC)