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Human Conception Ratio

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General fitness, health and nutrition
Published
14 February 2004
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25 February 2004
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Rick
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  1. Tim Tyler <[email hidden]> wrote or quoted:

    Quoted message said:

    I, Tim Tyler <[email hidden]> wrote or quoted:

    Quoted message said:
    Quoted message said:

    When I last looked into this, the most likely theory seemed to be differential sperm swimming
    speed.

    However it seems to be "inconceivable" that this could produce such a large conception bias ;-)

    If there's a bias, it would be interesting to know if it is male-determined or female-
    determined. [...]

    Sperm generation seems the most obvious place to look - but:

    about 51.3%, whereas the overall percentage of Y-chromosome bearing spermatozoa in our study
    samples was 50.3%, i.e. 1% closer to the proportion expected by Mendelian segregation. The
    observed difference

    - humrep.oupjournals.org2917

    It looks like the "faster swimmers" tale is /still/ the most likely one.

    of the course they must swim ;-)
    --
    __________
    |im |yler timtyler.orgtimtyler.org [email hidden] Remove lock to reply.

  2. Quoted message said:

    humans and I will just point out that to do a Fisher type calculation you need to know the
    investment cost of female and male offspring. That can be extraordinarily difficult to calculate
    for humans because it can vary from culture to culture. I give you the extreme example of India
    where there is a very high "dowry cost" for females. If you

    Quoted message said:

    ratio seen in India.
    William L Hunt


    If the investment costs vary from culture to culture it does not seem to be reflected in the
    birth ratio.

    Take a look at this page which shows the ratio for all countries and even includes a colour coded
    map (which is not designed for genetically abnormal people like me, i.e. colour-blind):

    You can see that Africa shows a trend for a lower ratio of males but in general the differences are
    fairly small. The stats for India are close to average.

  3. William L Hunt said:


    dkomo said:
    Quoted message said:

    Tim Tyler wrote:


    dkomo <[email hidden]> wrote or quoted:

    Quoted message said:
    Quoted message said:

    Web pages of unknown origin are not necessarily good resources.

    This was a set of lecture notes from a course at University College London:

    ucl.ac.ukucl.ac.uk

    Quoted message said:
    Quoted message said:


    ucl.ac.ukc339


    I'll just point out that Tim is being a little harsh because the
    website makes clear they "assume" equal investment cost for male and

    Quoted message said:

    ratio of 1:1.

    Please be advised that I don't by any means consider the argument about what Fisher actually said to
    be concluded. I think both you and Tim Tyler are wrong. Fisher never used terminology like "equal

    in my previous post where I quoted from the lecture notes.

    I've carried this as far as I can for the moment because I don't have time to run off to the local
    university library and reference Fisher's

    ratio theory. I'm instead relying on secondary sources which I have on hand which are
    interpretations of Fisher's theory.

    You can simply provide the relevant quote from Fisher's book to prove me wrong, and I'll accept that
    -- but only that.

    theory by people like Hamilton and Trivers used the concept of investment in offspring.

    Quoted message said:

    humans and I will just point out that to do a Fisher type calculation you need to know the
    investment cost of female and male offspring. That can be extraordinarily difficult to calculate
    for humans because it can vary from culture to culture. I give you the extreme example of India
    where there is a very high "dowry cost" for females. If you

    Quoted message said:

    ratio seen in India.
    William L Hunt

    Quoted message said:
    Quoted message said:

    This one is not correct.

    The correct prediction (due to Fisher) is that parents will invest

    Quoted message said:
    Quoted message said:
    Quoted message said:

    web page says:

    ``Eventually, the population will be made up of equal numbers of males and females.''

    It doesn't follow that:

    Quoted message said:
    Quoted message said:
    Quoted message said:

    originally developed by Fisher, is wrong, or the statistics cited are in error.''

    ...since Fisher's theory is not in conflict with a biased adult

    Quoted message said:
    Quoted message said:
    Quoted message said:

    --
    __________
    |im |yler timtyler.orgtimtyler.org [email hidden] Remove lock to reply.


    [email hidden]

  4. birth and "less than 15 years" are reported same at 1.05. More importantly it shows an increase to
    1.09 for the "15-65 years" category, which is quite contrary to what has been discussed in this
    thread. The ratio does come down to 0.9 after 65 years, but natural selection should be less
    relevant in this category.(or may be not???)

    Aside, stray female foeticide cases have been reported in India which are

    extent.

    Srinivas S

    Rick said:
    Quoted message said:

    humans and I will just point out that to do a Fisher type calculation you need to know the
    investment cost of female and male offspring. That can be extraordinarily difficult to calculate
    for humans because it can vary from culture to culture. I give you the extreme example of India
    where there is a very high "dowry cost" for females. If you

    Quoted message said:
    Quoted message said:

    ratio seen in India.
    William L Hunt


    If the investment costs vary from culture to culture it does not seem to be reflected in the
    birth ratio.

    Take a look at this page which shows the ratio for all countries and even includes a colour coded
    map (which is not designed for genetically abnormal people like me, i.e. colour-blind):

    Quoted message said:


    You can see that Africa shows a trend for a lower ratio of males but in general the differences
    are fairly small. The stats for India are close to average.

    --
    ----------------------------------------
    Who sees with equal eye, as God of all,
    A hero perish or a sparrow fall,
    Atoms or systems into ruin hurl’d,
    And now a bubble burst, and now a world.

  5. Rick <[email hidden]> wrote or quoted:

    Quoted message said:

    If the investment costs vary from culture to culture it does not seem to be reflected in the
    birth ratio.

    Take a look at this page which shows the ratio for all countries and even includes a colour coded
    map [...]:

    *Something* funny is going on:

    Here: Bermuda 0.94 male(s)/female here: Guam 1.14 male(s)/female ...and... here: Cayman Islands 0.86
    male(s)/female ...though.

    The lowest figures are:

    216. Barbados 1.01 male(s)/female
    217. Liechtenstein 1.01 male(s)/female
    218. Faroe Islands 1 male(s)/female
    219. Grenada 1 male(s)/female
    220. Bermuda 0.94 male(s)/female
    221. Cayman Islands 0.86 male(s)/female

    It looks like there may be a "small island" effect.
    --
    __________
    |im |yler timtyler.orgtimtyler.org [email hidden] Remove lock to reply.

  6. On Fri, 20 Feb 2004 17:00:33 +0000 (UTC), dkomo <[email hidden]>

    Quoted message said:
    William L Hunt said:


    dkomo said:

    >Tim Tyler wrote:
    dkomo <[email hidden]> wrote or quoted:

    Quoted message said:

    > Web pages of unknown origin are not necessarily good resources.
    >

    This was a set of lecture notes from a course at University College London:

    ucl.ac.ukucl.ac.uk

    Quoted message said:
    Quoted message said:
    Quoted message said:


    ucl.ac.ukc339


    I'll just point out that Tim is being a little harsh because the
    website makes clear they "assume" equal investment cost for male and

    Quoted message said:
    Quoted message said:

    ratio of 1:1.

    Please be advised that I don't by any means consider the argument about what Fisher actually
    said to be concluded. I think both you and Tim Tyler are wrong. Fisher never used terminology
    like "equal

    Quoted message said:

    in my previous post where I quoted from the lecture notes.

    I've carried this as far as I can for the moment because I don't have time to run off to the local
    university library and reference Fisher's

    Quoted message said:

    ratio theory. I'm instead relying on secondary sources which I have on hand which are
    interpretations of Fisher's theory.

    You can simply provide the relevant quote from Fisher's book to prove me wrong, and I'll accept
    that -- but only that.


    I'll quote from the website you provided (lecture notes):

    If males are twice as costly to produce as females, then males are only worth producing if they have
    twice the reproductive success of females. This will occur when there are twice as many females as
    males in the population. That

    be weighted by the cost of producing this

    Why would you think this is not also from Fisher when they are saying it is? Or why would you
    accept what they say is from Fisher in one section but not what they say is from Fisher in another?
    I would also have to reference Fisher's book to be sure what he "exactly" said. William L Hunt

    ... [snip] ...

    Quoted message said:

    [email hidden]

  7. dkomo <[email hidden]> wrote or quoted:

    Quoted message said:

    Please be advised that I don't by any means consider the argument about what Fisher actually
    said to be concluded. I think both you and Tim Tyler are wrong. Fisher never used terminology
    like "equal

    Quoted message said:

    in my previous post where I quoted from the lecture notes.

    Fisher's exact words were:

    itself under the influence of Natural Selection, that the total parental expenditure incurred in
    respect of children

    the total expenditure incurred in producing males were less than the total expenditure incurred in
    producing females, then since the total reproductive value of the males is equal to that of the
    females, it would follow that those parents, the innate tendencies of which caused them to produce
    males in excess, would, for the same expenditure, produce a greater amouunt of reproductive value
    : and in consequence would be the progenitors of a larger fraction of future generations than
    would the parents having a congential bias towards the production of females.''

    - The Genetical Theory of Natural Selection, Ronald Aylmer Fisher, Page 142.

    The key bit is:

    ``total parental expenditure incurred in respect of children

    --
    __________
    |im |yler timtyler.orgtimtyler.org [email hidden] Remove lock to reply.

  8. Quoted message said:

    *Something* funny is going on:

    Here: Bermuda 0.94 male(s)/female here: Guam 1.14 male(s)/female ...and... here: Cayman Islands
    0.86 male(s)/female ...though.

    The lowest figures are:

    216. Barbados 1.01 male(s)/female
    217. Liechtenstein 1.01 male(s)/female
    218. Faroe Islands 1 male(s)/female
    219. Grenada 1 male(s)/female
    220. Bermuda 0.94 male(s)/female
    221. Cayman Islands 0.86 male(s)/female

    It looks like there may be a "small island" effect.

    Or more likely just that small populations are more likely to deviate from the average. They will
    tend to the average but a 10% deviation is much more likely than in a very large population.

  9. Rick <[email hidden]> wrote or quoted:

    Quoted message said:
    Quoted message said:

    *Something* funny is going on:

    Here: Bermuda 0.94 male(s)/female here: Guam 1.14 male(s)/female ...and... here: Cayman Islands
    0.86 male(s)/female ...though.

    The lowest figures are:

    216. Barbados 1.01 male(s)/female
    217. Liechtenstein 1.01 male(s)/female
    218. Faroe Islands 1 male(s)/female
    219. Grenada 1 male(s)/female
    220. Bermuda 0.94 male(s)/female
    221. Cayman Islands 0.86 male(s)/female

    It looks like there may be a "small island" effect.

    Or more likely just that small populations are more likely to deviate from the average. They will
    tend to the average but a 10% deviation is much more likely than in a very large population.

    That hypothesis predicts deviations in both directions:

    1. Guam 1.14 male(s)/female [Island]
    2. Korea, South 1.11 male(s)/female
    3. China 1.09 male(s)/female
    4. Malta 1.09 male(s)/female [Island]
    5. San Marino 1.09 male(s)/female [Island]
    6. Iceland 1.08 male(s)/female
    7. Jersey 1.08 male(s)/female [Island]
    8. Macedonia, 1.08 male(s)/female
    9. Singapore 1.08 male(s)/female
    10. Tunisia 1.08 male(s)/female

    There seem to be some islands at the other end of the scale as well. An effect due to small sample
    sizes does seem likely.
    --
    __________
    |im |yler timtyler.orgtimtyler.org [email hidden] Remove lock to reply.

  10. William L Hunt said:
    dkomo said:
    William L Hunt said:


    On Wed, 18 Feb 2004 22:57:56 +0000 (UTC), dkomo <[email hidden]> wrote:

    >>Tim Tyler wrote:
    > dkomo <[email hidden]> wrote or quoted:

    >> Web pages of unknown origin are not necessarily good resources.
    >>
    >
    >This was a set of lecture notes from a course at University College London:
    >
    >ucl.ac.ukucl.ac.uk
    >

    Quoted message said:
    Quoted message said:
    Quoted message said:

    >
    >ucl.ac.ukc339
    >
    I'll just point out that Tim is being a little harsh because the
    website makes clear they "assume" equal investment cost for male and

    Quoted message said:
    Quoted message said:
    Quoted message said:

    ratio of 1:1.

    Please be advised that I don't by any means consider the argument about what Fisher actually
    said to be concluded. I think both you and Tim Tyler are wrong. Fisher never used terminology
    like "equal

    Quoted message said:
    Quoted message said:

    in my previous post where I quoted from the lecture notes.

    I've carried this as far as I can for the moment because I don't have time to run off to the
    local university library and reference Fisher's

    Quoted message said:
    Quoted message said:

    ratio theory. I'm instead relying on secondary sources which I have on hand which are
    interpretations of Fisher's theory.

    You can simply provide the relevant quote from Fisher's book to prove me wrong, and I'll accept
    that -- but only that.


    I'll quote from the website you provided (lecture notes):

    Quoted message said:

    If males are twice as costly to produce as females, then males are only worth producing if they
    have twice the reproductive success of females. This will occur when there are twice as many
    females as males in the population. That

    Quoted message said:

    be weighted by the cost of producing this

    Quoted message said:


    Why would you think this is not also from Fisher when they are saying it is? Or why would you
    accept what they say is from Fisher in one section but not what they say is from Fisher in
    another? I would also have to reference Fisher's book to be sure what he "exactly" said.
    William L Hunt

    ... [snip] ...

    Quoted message said:

    [email hidden]

    Page 158ff in the 1958 edition (but no apparent resetting from the 1930 edition); excuse typos:

    In organisms of all kinds the young are launched upon their careers endowed with a certain amount of
    biological capital derived from their parents. This varies enormously in amount in different
    species, but, all in all, there has been, before the offspring is able to lead an independent
    existence, a certain expenditure of nutriment in addition, almost universally, to some expenditure
    of time or activity, which the parents are induced by their instincts to make for the advantage of
    their young. Let us consider the reproductive value of these off-[159]spring at the moment when this
    parental expenditure on their behalf has ceased. If we consider the aggregate of an entire
    generation of such offspring it is clear that the total reproductive value of the males in this
    group is exactly equal to the total value of all the

    adjust itself, under the influence of Natural Selection, that the total

    be equal; for if this were not so and the total expenditure incurred in producing males, for
    instance, were less than the total expenditure incurred in producing females, then since the total
    reproductive value of the males is equal to that of the females, it would follow that those parents,
    the innate tendencies of which caused them to produce males in excess, would, for the same
    expenditure, produce a greater amount of reproductive value; and in consequence would be the
    progenitors of a larger fraction of future generations than would parent having a congenital bias
    towards the production of females....

    the differential mortailty during that period, and if there are [160] such differences, upon which
    the differential demands which the young of such species make during their period of dependency; it
    will not be infulenced by differential mortality during a self-supporting period;

    influenced without compensation, by differential mortality during the period intervening between the
    period of dependence and the attainment of maturity. Any great differential mortality in this period
    will, however, tend to be checked by Natural Selection, owing to the fact that

    to the other, whichever is the scarcer, will be the more valuable, and consequently a more intense
    selection will be exerted in favour of all modifications tending towards its preservation. The
    numbers attaining

    form or habits is thus for other reasons advantageous, but any great and

    value. <eq>

    God, there was a man who knew how to use a comma...
    --
    John Wilkins [email hidden] wilkins.id.auwilkins.id.au "Men mark it when they hit, but do not
    mark it when they miss"
    - Francis Bacon

  11. Tim Tyler said:


    dkomo <[email hidden]> wrote or quoted:

    Quoted message said:

    Please be advised that I don't by any means consider the argument about what Fisher actually
    said to be concluded. I think both you and Tim Tyler are wrong. Fisher never used terminology
    like "equal

    Quoted message said:
    Quoted message said:

    in my previous post where I quoted from the lecture notes.

    Fisher's exact words were:

    Quoted message said:

    itself under the influence of Natural Selection, that the total parental expenditure incurred in
    respect of children

    Quoted message said:

    the total expenditure incurred in producing males were less than the total expenditure incurred
    in producing females, then since the total reproductive value of the males is equal to that of
    the females, it would follow that those parents, the innate tendencies of which caused them to
    produce males in excess, would, for the same expenditure, produce a greater amouunt of
    reproductive value : and in consequence would be the progenitors of a larger fraction of future
    generations than would the parents having a congential bias towards the production of females.''

    - The Genetical Theory of Natural Selection, Ronald Aylmer Fisher, Page 142.

    The key bit is:

    ``total parental expenditure incurred in respect of children

    Ok, I was wrong about what Fisher wrote, having been misled by my secondary sources, which not
    only dumbed-down Fisher's ideas, but changed the emphasis from expenditure over to pure
    numerical advantage

    An example:

    "The evolutionary process thought to underlie the 50/50 ratio was first modeled by R.A. Fisher
    (1930). In barest outline, 'Fisher's Principle' can be stated as follows. If male births in a
    population are less frequent than female births, each male has a better chance to mate than each
    female. All other things being equal, the male is more likely to find multiple partners. It follows
    that parents genetically predisposed to produce a higher proportion of males will ultimately have
    more grandchildren. But the tendency is self-negating in the population as a whole, since the
    advantage will be lost as the male-producing gene spreads and males become commoner. As a result

    Sociobiology -- The Abridged Edition, Edward O. Wilson, p 157.

    Later on down Wilson adds:

    "Subsequent authors have refined and extended this model to the point where the following more
    precise statement can be made. Ideally a

    make equal *investments* in them."

    It was this statement that made me think it wasn't Fisher who originated the idea of investment in
    offspring.

    [email hidden]

  12. John Wilkins said:


    William L Hunt said:
    dkomo said:

    William L Hunt wrote:
    >
    > On Wed, 18 Feb 2004 22:57:56 +0000 (UTC), dkomo <[email hidden]> wrote:
    >
    > >>Tim Tyler wrote:
    > > dkomo <[email hidden]> wrote or quoted:
    >
    > >> Web pages of unknown origin are not necessarily good resources.
    > >>
    > >
    > >This was a set of lecture notes from a course at University College London:
    > >
    > >ucl.ac.ukucl.ac.uk
    > >

    Quoted message said:
    Quoted message said:
    Quoted message said:

    > >
    > >ucl.ac.ukc339
    > >
    > I'll just point out that Tim is being a little harsh because the
    > website makes clear they "assume" equal investment cost for male and

    Quoted message said:
    Quoted message said:
    Quoted message said:

    > ratio of 1:1.

    Please be advised that I don't by any means consider the argument about what Fisher actually
    said to be concluded. I think both you and Tim Tyler are wrong. Fisher never used terminology
    like "equal

    Quoted message said:
    Quoted message said:
    Quoted message said:

    in my previous post where I quoted from the lecture notes.

    I've carried this as far as I can for the moment because I don't have time to run off to the
    local university library and reference Fisher's

    Quoted message said:
    Quoted message said:
    Quoted message said:

    ratio theory. I'm instead relying on secondary sources which I have on hand which are
    interpretations of Fisher's theory.

    You can simply provide the relevant quote from Fisher's book to prove me wrong, and I'll accept
    that -- but only that.


    I'll quote from the website you provided (lecture notes):

    Quoted message said:
    Quoted message said:

    If males are twice as costly to produce as females, then males are only worth producing if they
    have twice the reproductive success of females. This will occur when there are twice as many
    females as males in the population. That

    Quoted message said:
    Quoted message said:

    be weighted by the cost of producing this

    Quoted message said:
    Quoted message said:


    Why would you think this is not also from Fisher when they are saying it is? Or why would you
    accept what they say is from Fisher in one section but not what they say is from Fisher in
    another? I would also have to reference Fisher's book to be sure what he "exactly" said.
    William L Hunt

    ... [snip] ...

    Quoted message said:

    [email hidden]

    Page 158ff in the 1958 edition (but no apparent resetting from the 1930 edition); excuse typos:

    In organisms of all kinds the young are launched upon their careers endowed with a certain amount
    of biological capital derived from their parents. This varies enormously in amount in different
    species, but, all in all, there has been, before the offspring is able to lead an independent
    existence, a certain expenditure of nutriment in addition, almost universally, to some expenditure
    of time or activity, which the parents are induced by their instincts to make for the advantage of
    their young. Let us consider the reproductive value of these off-[159]spring at the moment when
    this parental expenditure on their behalf has ceased. If we consider the aggregate of an entire
    generation of such offspring it is clear that the total reproductive value of the males in this
    group is exactly equal to the total value of all the

    Quoted message said:

    adjust itself, under the influence of Natural Selection, that the total

    Quoted message said:

    be equal; for if this were not so and the total expenditure incurred in producing males, for
    instance, were less than the total expenditure incurred in producing females, then since the total
    reproductive value of the males is equal to that of the females, it would follow that those
    parents, the innate tendencies of which caused them to produce males in excess, would, for the
    same expenditure, produce a greater amount of reproductive value; and in consequence would be the
    progenitors of a larger fraction of future generations than would parent having a congenital bias
    towards the production of females....

    Quoted message said:

    the differential mortailty during that period, and if there are [160] such differences, upon which
    the differential demands which the young of such species make during their period of dependency;
    it will not be infulenced by differential mortality during a self-supporting period;

    Quoted message said:

    influenced without compensation, by differential mortality during the period intervening between
    the period of dependence and the attainment of maturity. Any great differential mortality in this
    period will, however, tend to be checked by Natural Selection, owing to the fact that

    Quoted message said:

    to the other, whichever is the scarcer, will be the more valuable, and consequently a more intense
    selection will be exerted in favour of all modifications tending towards its preservation. The
    numbers attaining

    Quoted message said:

    form or habits is thus for other reasons advantageous, but any great and

    Quoted message said:

    value. <eq>

    God, there was a man who knew how to use a comma...
    --

    And semicolons. And long paragraphs.

    I ran across a number of comments on the web about _Genetical Theory of Natural Selection_. Many
    biologists consider Fisher's book to be second in importance only to _Origin of Species_ for the
    theory of evolution. Fisher, however, ranks far down the list from Darwin for prose style, IMHO.

    [email hidden]

  13. dkomo <[email hidden]> wrote or quoted:

    Quoted message said:

    An example:

    "The evolutionary process thought to underlie the 50/50 ratio was first modeled by R.A. Fisher
    (1930). [...]

    Pah! That was Darwin's idea:

    Darwin gives the correct argument - and concludes:

    about.''

    - First edition of "The Descent Of Man".

    Fisher is widely believed to have got the idea from J. A. Cobb - who, in 1914, gave the full
    argument complete with the

    --
    __________
    |im |yler timtyler.orgtimtyler.org [email hidden] Remove lock to reply.

  14. On Mon, 23 Feb 2004 06:56:01 +0000 (UTC), Tim Tyler <[email hidden]>

    Quoted message said:

    dkomo <[email hidden]> wrote or quoted:

    Quoted message said:

    An example:

    "The evolutionary process thought to underlie the 50/50 ratio was first modeled by R.A. Fisher
    (1930). [...]

    Pah! That was Darwin's idea:

    Quoted message said:


    Darwin gives the correct argument - and concludes:

    Quoted message said:

    about.''

    - First edition of "The Descent Of Man".

    Fisher is widely believed to have got the idea from J. A. Cobb - who, in 1914, gave the full
    argument complete with the

    Quoted message said:

    --

    The contributions of Dusing were once the subject of thread in sbe. I quote from an article in Theo
    Pop Biol, Nov 2000:

    "In three publications in 1883 and 1884 Carl Dusing of Jena gave a

    ratio based on the same argument that Darwin had advanced in The Descent of Man (1871). The argument
    thus became quite well known, being included in the principal books on the subject around the turn
    of the century, as well as in the Encyclopaedia Britannica, references to Dusing being given. By
    1930, when Fisher gave a verbal account of the argument in The Genetical Theory of Natural
    Selection, he saw no need to give references, and no other book of the period treated the subject,
    as a result of which Dusing's contribution became lost to view." William L Hunt

    Quoted message said:

    __________
    |im |yler timtyler.orgtimtyler.org [email hidden] Remove lock to reply.

  15. dkomo said:
    John Wilkins said:


    William L Hunt said:

    On Fri, 20 Feb 2004 17:00:33 +0000 (UTC), dkomo <[email hidden]> wrote:

    > William L Hunt wrote:
    >>
    >> On Wed, 18 Feb 2004 22:57:56 +0000 (UTC), dkomo <[email hidden]> wrote:
    >>
    >>>> Tim Tyler wrote:
    >>> dkomo <[email hidden]> wrote or quoted:
    >>
    >>>> Web pages of unknown origin are not necessarily good resources.
    >>>>
    >>>
    >>> This was a set of lecture notes from a course at University College London:
    >>>
    >>> ucl.ac.ukucl.ac.uk
    >>>

    Quoted message said:
    Quoted message said:
    Quoted message said:

    >>>
    >>> ucl.ac.ukc339
    >>>
    >> I'll just point out that Tim is being a little harsh because the website makes clear they
    >> "assume" equal investment cost for male and female offspring. From that "assumption" they
    >> derive/use a primary

    Quoted message said:
    Quoted message said:
    Quoted message said:

    >> ratio of 1:1.
    >
    > Please be advised that I don't by any means consider the argument about what Fisher actually
    > said to be concluded. I think both you and Tim Tyler are wrong. Fisher never used terminology
    > like "equal

    Quoted message said:
    Quoted message said:
    Quoted message said:

    > stated in my previous post where I quoted from the lecture notes.
    >
    > I've carried this as far as I can for the moment because I don't have time to run off to the
    > local university library and reference Fisher's

    Quoted message said:
    Quoted message said:
    Quoted message said:

    > ratio theory. I'm instead relying on secondary sources which I have on hand which are
    > interpretations of Fisher's theory.
    >
    > You can simply provide the relevant quote from Fisher's book to prove me wrong, and I'll accept
    > that -- but only that.
    >
    I'll quote from the website you provided (lecture notes):

    Quoted message said:
    Quoted message said:
    Quoted message said:

    If males are twice as costly to produce as females, then males are only worth producing if they
    have twice the reproductive success of females. This will occur when there are twice as many
    females as males in the population. That

    Quoted message said:
    Quoted message said:
    Quoted message said:

    be weighted by the cost of producing this

    Quoted message said:
    Quoted message said:
    Quoted message said:


    Why would you think this is not also from Fisher when they are saying it is? Or why would you
    accept what they say is from Fisher in one section but not what they say is from Fisher in
    another? I would also have to reference Fisher's book to be sure what he "exactly" said.
    William L Hunt

    ... [snip] ...
    > [email hidden]
    >

    Page 158ff in the 1958 edition (but no apparent resetting from the 1930 edition); excuse typos:


    <snip>

    Quoted message said:
    Quoted message said:

    God, there was a man who knew how to use a comma...
    --

    And semicolons. And long paragraphs.

    I ran across a number of comments on the web about _Genetical Theory of Natural Selection_. Many
    biologists consider Fisher's book to be second in importance only to _Origin of Species_ for the
    theory of evolution. Fisher, however, ranks far down the list from Darwin for prose style, IMHO.


    It was noted in the obits for William Hamilton that he had hoped at the end of his life to get a
    first in Fisher's GToNS. The book is deep - really deep, despite the eugenics of the latter half.
    The reason why I typed all that out by hand was to read it in detail (a process that works well for
    me, as I'm a lousy typist and have to proofread carefully). It was worth it. I now have about six
    independent lines of thought from those two paragraphs...

    --
    John Wilkins [email hidden] wilkins.id.auwilkins.id.au "Men mark it when they hit, but do not
    mark it when they miss"
    - Francis Bacon

    --
    John S Wilkins Head, Communication Services The Walter and Eliza Hall Institute of Medical Research
    Parkville, Victoria, Australia

  16. dkomo said:
    John Wilkins said:


    William L Hunt said:

    On Fri, 20 Feb 2004 17:00:33 +0000 (UTC), dkomo <[email hidden]> wrote:

    >William L Hunt wrote:
    >>
    >> On Wed, 18 Feb 2004 22:57:56 +0000 (UTC), dkomo <[email hidden]> wrote:
    >>
    >> >>Tim Tyler wrote:
    >> > dkomo <[email hidden]> wrote or quoted:
    >>
    >> >> Web pages of unknown origin are not necessarily good resources.
    >> >>
    >> >
    >> >This was a set of lecture notes from a course at University College London:
    >> >
    >> >ucl.ac.ukucl.ac.uk
    >> >

    Quoted message said:
    Quoted message said:
    Quoted message said:

    >> >
    >> >ucl.ac.ukc339
    >> >
    >> I'll just point out that Tim is being a little harsh because the
    >> website makes clear they "assume" equal investment cost for male and

    Quoted message said:
    Quoted message said:
    Quoted message said:

    >> ratio of 1:1.
    >
    >Please be advised that I don't by any means consider the argument about what Fisher actually
    >said to be concluded. I think both you and Tim Tyler are wrong. Fisher never used terminology
    >like "equal

    Quoted message said:
    Quoted message said:
    Quoted message said:

    >in my previous post where I quoted from the lecture notes.
    >
    >I've carried this as far as I can for the moment because I don't have time to run off to the
    >local university library and reference Fisher's

    Quoted message said:
    Quoted message said:
    Quoted message said:

    >ratio theory. I'm instead relying on secondary sources which I have on hand which are
    >interpretations of Fisher's theory.
    >
    >You can simply provide the relevant quote from Fisher's book to prove me wrong, and I'll
    >accept that -- but only that.
    >
    I'll quote from the website you provided (lecture notes):

    Quoted message said:
    Quoted message said:
    Quoted message said:

    If males are twice as costly to produce as females, then males are only worth producing if
    they have twice the reproductive success of females. This will occur when there are twice as
    many females as males in the population. That

    Quoted message said:
    Quoted message said:
    Quoted message said:

    be weighted by the cost of producing this

    Quoted message said:
    Quoted message said:
    Quoted message said:


    Why would you think this is not also from Fisher when they are saying it is? Or why would you
    accept what they say is from Fisher in one section but not what they say is from Fisher in
    another? I would also have to reference Fisher's book to be sure what he "exactly" said.
    William L Hunt

    ... [snip] ...
    > [email hidden]
    >

    Page 158ff in the 1958 edition (but no apparent resetting from the 1930 edition); excuse typos:

    In organisms of all kinds the young are launched upon their careers endowed with a certain
    amount of biological capital derived from their parents. This varies enormously in amount in
    different species, but, all in all, there has been, before the offspring is able to lead an
    independent existence, a certain expenditure of nutriment in addition, almost universally, to
    some expenditure of time or activity, which the parents are induced by their instincts to make
    for the advantage of their young. Let us consider the reproductive value of these off-
    [159]spring at the moment when this parental expenditure on their behalf has ceased. If we
    consider the aggregate of an entire generation of such offspring it is clear that the total
    reproductive value of the males in this group is exactly equal to the total value of all the

    Quoted message said:
    Quoted message said:

    adjust itself, under the influence of Natural Selection, that the total

    Quoted message said:
    Quoted message said:

    be equal; for if this were not so and the total expenditure incurred in producing males, for
    instance, were less than the total expenditure incurred in producing females, then since the
    total reproductive value of the males is equal to that of the females, it would follow that
    those parents, the innate tendencies of which caused them to produce males in excess, would, for
    the same expenditure, produce a greater amount of reproductive value; and in consequence would
    be the progenitors of a larger fraction of future generations than would parent having a
    congenital bias towards the production of females....

    Quoted message said:
    Quoted message said:

    the differential mortailty during that period, and if there are [160] such differences, upon
    which the differential demands which the young of such species make during their period of
    dependency; it will not be infulenced by differential mortality during a self-supporting period;

    Quoted message said:
    Quoted message said:

    influenced without compensation, by differential mortality during the period intervening between
    the period of dependence and the attainment of maturity. Any great differential mortality in
    this period will, however, tend to be checked by Natural Selection, owing to the fact that

    Quoted message said:
    Quoted message said:

    to the other, whichever is the scarcer, will be the more valuable, and consequently a more
    intense selection will be exerted in favour of all modifications tending towards its
    preservation. The numbers attaining

    Quoted message said:
    Quoted message said:

    form or habits is thus for other reasons advantageous, but any great and

    Quoted message said:
    Quoted message said:

    value. <eq>

    God, there was a man who knew how to use a comma...
    --

    And semicolons. And long paragraphs.

    I ran across a number of comments on the web about _Genetical Theory of Natural Selection_. Many
    biologists consider Fisher's book to be second in importance only to _Origin of Species_ for the
    theory of evolution. Fisher, however, ranks far down the list from Darwin for prose style, IMHO.


    It was noted in the obits for William Hamilton that he had hoped at the end of his life to get a
    first in Fisher's GToNS. The book is deep - really deep, despite the eugenics of the latter half.
    The reason why I typed all that out by hand was to read it in detail (a process that works well for
    me, as I'm a lousy typist and have to proofread carefully). It was worth it. I now have about six
    independent lines of thought from those two paragraphs...

    --
    John Wilkins [email hidden] wilkins.id.auwilkins.id.au "Men mark it when they hit, but do not
    mark it when they miss"
    - Francis Bacon

  17. ...

    Quoted message said:

    It was noted in the obits for William Hamilton that he had hoped at the end of his life to get a
    first in Fisher's GToNS. The book is deep - really deep, despite the eugenics of the latter half.
    The reason why I typed all that out by hand was to read it in detail (a process that works well
    for me, as I'm a lousy typist and have to proofread carefully). It was worth it. I now have about
    six independent lines of thought from those two paragraphs...

    Apologies for the duplication - my server went pear shaped for a day, and then Our Moderator
    manually posted it at my request.
    --
    Our Moderator, Who Art in Seattle... John Wilkins [email hidden] wilkins.id.auwilkins.id.au
    "Men mark it when they hit, but do not mark it when they miss"
    - Francis Bacon

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