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Well, so much for the old "we've never seen it happen, so it can't."
http://www.geneticarchaeology.com/research/Study_catches_2_bird_populations_as_they_split_into_separate_species.asp
--
Darren New, San Diego CA, USA (PST)
"We'd like you to back-port all the changes in 2.0
back to version 1.0."
"We've done that already. We call it 2.0."
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"Darren New" <dne### [at] san rrcom> wrote in message
news:4a60b186$1@news.povray.org...
> Well, so much for the old "we've never seen it happen, so it can't."
>
>
http://www.geneticarchaeology.com/research/Study_catches_2_bird_populations_as_they_split_into_separate_species.asp
It's somewhat of a stretch, and similar to saying that since Asian males
don't see African males as much a threat as they see Asian males, and vice
versa, that we are at a speciation crossroads.
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On 17-7-2009 22:17, somebody wrote:
> "Darren New" <dne### [at] sanrrcom> wrote in message
> news:4a60b186$1@news.povray.org...
>
>> Well, so much for the old "we've never seen it happen, so it can't."
>>
>>
>
http://www.geneticarchaeology.com/research/Study_catches_2_bird_populations_as_they_split_into_separate_species.asp
>
> It's somewhat of a stretch, and similar to saying that since Asian males
> don't see African males as much a threat as they see Asian males, and vice
> versa,
well, do they?
> that we are at a speciation crossroads.
what makes you think we aren't?
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"andrel" <a_l### [at] hotmailcom> wrote in message
news:4A6### [at] hotmailcom...
> On 17-7-2009 22:17, somebody wrote:
> > "Darren New" <dne### [at] sanrrcom> wrote in message
> > news:4a60b186$1@news.povray.org...
> >
> >> Well, so much for the old "we've never seen it happen, so it can't."
> >>
> >>
> >
http://www.geneticarchaeology.com/research/Study_catches_2_bird_populations_as_they_split_into_separate_species.asp
> >
> > It's somewhat of a stretch, and similar to saying that since Asian males
> > don't see African males as much a threat as they see Asian males, and
vice
> > versa,
> well, do they?
I don't know. But since "interracial" marriages are more exception than
norm, however you define race, it's not unreasonable and could be the
subject of a social study.
> > that we are at a speciation crossroads.
> what makes you think we aren't?
My point is, why that should make us think that we are?
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On 17-7-2009 22:35, somebody wrote:
> "andrel" <a_l### [at] hotmailcom> wrote in message
> news:4A6### [at] hotmailcom...
>> On 17-7-2009 22:17, somebody wrote:
>>> "Darren New" <dne### [at] sanrrcom> wrote in message
>>> news:4a60b186$1@news.povray.org...
>>>
>>>> Well, so much for the old "we've never seen it happen, so it can't."
>>>>
>>>>
>
http://www.geneticarchaeology.com/research/Study_catches_2_bird_populations_as_they_split_into_separate_species.asp
>>> It's somewhat of a stretch, and similar to saying that since Asian males
>>> don't see African males as much a threat as they see Asian males, and
> vice
>>> versa,
>
>> well, do they?
>
> I don't know. But since "interracial" marriages are more exception than
> norm, however you define race, it's not unreasonable and could be the
> subject of a social study.
intercultural and intersubcultural and intersocial mariages are
uncommon. interracial is just correlated with that. At least from my
point of view, which is one from a subculture where race is not an
issue. Race is for me just as relevant as length or haircolor. I notice
it but it doesn't turn me on or off. I the group of people that I
usually encounter race also does not seem an issue, lots of interracial
pairs.
Or to put it at a more personal level: do you fancy any white, black, or
asian (etc) movie stars, musicians, or ordinary people you met?
>>> that we are at a speciation crossroads.
>
>> what makes you think we aren't?
>
> My point is, why that should make us think that we are?
Because of the definition of a species. If two groups don't mix they are
two separate species (or if you you the stricter definition of unable to
mix, they will inevitably be soon).
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somebody wrote:
> I don't know. But since "interracial" marriages are more exception than
> norm,
I think that's more because races don't mix all that much. How many African
folks are there in Japan to get married?
I think when you're in a place that has lots of different "races" mixed
together, you get a fair amount of interracial marriages, just from personal
gut feeling and nothing scientific.
--
Darren New, San Diego CA, USA (PST)
"We'd like you to back-port all the changes in 2.0
back to version 1.0."
"We've done that already. We call it 2.0."
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"andrel" <a_l### [at] hotmailcom> wrote in message
news:4A6### [at] hotmailcom...
> On 17-7-2009 22:35, somebody wrote:
> > "andrel" <a_l### [at] hotmailcom> wrote in message
> > news:4A6### [at] hotmailcom...
> >> On 17-7-2009 22:17, somebody wrote:
> >>> "Darren New" <dne### [at] sanrrcom> wrote in message
> >>> news:4a60b186$1@news.povray.org...
> >>>
> >>>> Well, so much for the old "we've never seen it happen, so it can't."
> >>>>
> >>>>
> >
http://www.geneticarchaeology.com/research/Study_catches_2_bird_populations_as_they_split_into_separate_species.asp
> >>> It's somewhat of a stretch, and similar to saying that since Asian
males
> >>> don't see African males as much a threat as they see Asian males, and
> > vice
> >>> versa,
> >
> >> well, do they?
> >
> > I don't know. But since "interracial" marriages are more exception than
> > norm, however you define race, it's not unreasonable and could be the
> > subject of a social study.
> intercultural and intersubcultural and intersocial mariages are
> uncommon. interracial is just correlated with that. At least from my
> point of view, which is one from a subculture where race is not an
> issue. Race is for me just as relevant as length or haircolor. I notice
> it but it doesn't turn me on or off. I the group of people that I
> usually encounter race also does not seem an issue, lots of interracial
> pairs.
>
> Or to put it at a more personal level: do you fancy any white, black, or
> asian (etc) movie stars, musicians, or ordinary people you met?
There are of course exceptions, but if I were to statistically analyze, I'd
be surprised if, on average, I did not find Europeans and likely Middle
Easterners to be more attractive than geographically more distant peoples. I
don't disagree that it's not cultural, I've had little exposure to, say,
east indian TV or culture, and have not been brainwashed by their norms of
beauty. But that doesn't change the relevant aspect - that is, men hunting,
so to speak, in different domains and hence feeling less threatened by males
of the other race/culture/...etc does not automatically imply divergence of
species. It's impretive that evolutionary biologists do not make
unjustifable leaps in their reasoning so as not to give ammunition to
creationists.
> >>> that we are at a speciation crossroads.
> >
> >> what makes you think we aren't?
> >
> > My point is, why that should make us think that we are?
> Because of the definition of a species. If two groups don't mix they are
> two separate species (or if you you the stricter definition of unable to
> mix, they will inevitably be soon).
That's not inevitable. Physical separation for N number of generations is
not an automatic guarantee of speciation for any N, as far as I am aware.
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On 18-7-2009 1:37, somebody wrote:
> "andrel" <a_l### [at] hotmailcom> wrote in message
> news:4A6### [at] hotmailcom...
>> On 17-7-2009 22:35, somebody wrote:
>>> "andrel" <a_l### [at] hotmailcom> wrote in message
>>> news:4A6### [at] hotmailcom...
>>>> On 17-7-2009 22:17, somebody wrote:
>>>>> "Darren New" <dne### [at] sanrrcom> wrote in message
>>>>> news:4a60b186$1@news.povray.org...
>>>>>
>>>>>> Well, so much for the old "we've never seen it happen, so it can't."
>>>>>>
>>>>>>
>
http://www.geneticarchaeology.com/research/Study_catches_2_bird_populations_as_they_split_into_separate_species.asp
>>>>> It's somewhat of a stretch, and similar to saying that since Asian
> males
>>>>> don't see African males as much a threat as they see Asian males, and
>>> vice
>>>>> versa,
>>>> well, do they?
>>> I don't know. But since "interracial" marriages are more exception than
>>> norm, however you define race, it's not unreasonable and could be the
>>> subject of a social study.
>
>> intercultural and intersubcultural and intersocial mariages are
>> uncommon. interracial is just correlated with that. At least from my
>> point of view, which is one from a subculture where race is not an
>> issue. Race is for me just as relevant as length or haircolor. I notice
>> it but it doesn't turn me on or off. I the group of people that I
>> usually encounter race also does not seem an issue, lots of interracial
>> pairs.
>>
>> Or to put it at a more personal level: do you fancy any white, black, or
>> asian (etc) movie stars, musicians, or ordinary people you met?
>
> There are of course exceptions, but if I were to statistically analyze, I'd
> be surprised if, on average, I did not find Europeans and likely Middle
> Easterners to be more attractive than geographically more distant peoples. I
> don't disagree that it's not cultural, I've had little exposure to, say,
> east indian TV or culture, and have not been brainwashed by their norms of
> beauty.
Some of them are even more beautiful by our standards than theirs. E.g.
a tan (suninduced ot congenital) is considered adding beauty to a female
here whereas at least for some in some groups in Japan you can not be
white enough. Hence some Japanese woman are more beautiful in Europe
than in their home country. (example not pulled from thin air).
> But that doesn't change the relevant aspect - that is, men hunting,
> so to speak, in different domains and hence feeling less threatened by males
> of the other race/culture/...etc does not automatically imply divergence of
> species.
If you talk about humanity, then I don't think it is useful to discuss
it, because your premise is false. White men will feel threatened if
their wife is in a pleasant conversation with a rich, well dressed black
male and skinny black males will feel the same if their wives are
talking to a white bodybuilder.
If this is about the example of these birds, it is slightly more
complicated. I would definitely like to see data on female behaviour. If
a female with a black father prefers all black males and likewise for
chestnut breasts the case would be even stronger. But this is research,
within the boundaries of their protocol they did only check male
behaviour. I personally think the case is already strong enough, and I
hope that it generates money for more research to make the case
undeniable for even the greatest sceptic (at least those that look at
data, you never convince an anti-scientific creationist).
> It's impretive that evolutionary biologists do not make
> unjustifable leaps in their reasoning so as not to give ammunition to
> creationists.
Sure, no doubt about that.
>>>>> that we are at a speciation crossroads.
>>>> what makes you think we aren't?
>>> My point is, why that should make us think that we are?
>
>> Because of the definition of a species. If two groups don't mix they are
>> two separate species (or if you you the stricter definition of unable to
>> mix, they will inevitably be soon).
>
> That's not inevitable. Physical separation for N number of generations is
> not an automatic guarantee of speciation for any N, as far as I am aware.
There is no fixed N as it is a stochastic process. There is also that
annoying thing that it is hard to define if two populations that are not
living at the same time are separate species or not. Example: you have a
species with two subgroups A and B that can interbreed but choose not
to. After some time you have groups A' and B' that can not interbreed
anymore. It is not unlikely that A' now also can not interbreed with A,
so is this A' still the same species as A?
Apart from that sort of technicalities, mutations will accumulate in
both groups, in genes that change the appearance, in genes that
influence the preference for a certain appearance, in genes that
influence the diet and thus the territory, and even less subtle changes
that span multiple genes.
You are not able to interbreed with chimps and bonobos. Not only because
you find them (probably) unattractive but also because our genes do not
match. Somewhere along the line two chromosomes fused to one bigger one,
so that we now have 23 pairs of them and the chimp still 24. There are
also some other large reshuffelings of genes that will prevent mixed
offspring. How the 46/48 chromosome hybrids ever were compatible is a
thing that amazes me everytime, but that is something for another
discussion.
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"andrel" <a_l### [at] hotmailcom> wrote in message
news:4A6### [at] hotmailcom...
> On 18-7-2009 1:37, somebody wrote:
> > There are of course exceptions, but if I were to statistically analyze,
I'd
> > be surprised if, on average, I did not find Europeans and likely Middle
> > Easterners to be more attractive than geographically more distant
peoples. I
> > don't disagree that it's not cultural, I've had little exposure to, say,
> > east indian TV or culture, and have not been brainwashed by their norms
of
> > beauty.
> Some of them are even more beautiful by our standards than theirs. E.g.
> a tan (suninduced ot congenital) is considered adding beauty to a female
> here whereas at least for some in some groups in Japan you can not be
> white enough. Hence some Japanese woman are more beautiful in Europe
> than in their home country. (example not pulled from thin air).
True. It might even be genetic features of an individual that may make one
less attractive to own group and more so to an outside population. Some
humans also seem to have an attraction to the exotic, which also makes it
more complicated. But these are perturbations to the basal preferences.
> > But that doesn't change the relevant aspect - that is, men hunting,
> > so to speak, in different domains and hence feeling less threatened by
males
> > of the other race/culture/...etc does not automatically imply divergence
of
> > species.
> If you talk about humanity, then I don't think it is useful to discuss
> it, because your premise is false. White men will feel threatened if
> their wife is in a pleasant conversation with a rich, well dressed black
> male and skinny black males will feel the same if their wives are
> talking to a white bodybuilder.
One can always construct special circumstances, or exceptions, that go
against the rule. You do have a point, however, if the rich black males
outnumber rich white males, or white bodybuilders outnumber black
bodybuilders in mixed populations, and if those qualifications are largely
deemed desirable by the females.
> If this is about the example of these birds, it is slightly more
> complicated. I would definitely like to see data on female behaviour. If
> a female with a black father prefers all black males and likewise for
> chestnut breasts the case would be even stronger. But this is research,
> within the boundaries of their protocol they did only check male
> behaviour. I personally think the case is already strong enough, and I
> hope that it generates money for more research to make the case
> undeniable for even the greatest sceptic (at least those that look at
> data, you never convince an anti-scientific creationist).
Yes, it should be studied. But the conclusion that "study caught populations
as they split into species" is premature and risky, IMO.
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On 18-7-2009 17:28, somebody wrote:
> "andrel" <a_l### [at] hotmailcom> wrote in message
> news:4A6### [at] hotmailcom...
>> On 18-7-2009 1:37, somebody wrote:
> Some
> humans also seem to have an attraction to the exotic, which also makes it
> more complicated. But these are perturbations to the basal preferences.
That may be your basal preference, it is not mine. ;)
>>> But that doesn't change the relevant aspect - that is, men hunting,
>>> so to speak, in different domains and hence feeling less threatened by
> males
>>> of the other race/culture/...etc does not automatically imply divergence
> of
>>> species.
>
>> If you talk about humanity, then I don't think it is useful to discuss
>> it, because your premise is false. White men will feel threatened if
>> their wife is in a pleasant conversation with a rich, well dressed black
>> male and skinny black males will feel the same if their wives are
>> talking to a white bodybuilder.
>
> One can always construct special circumstances, or exceptions, that go
> against the rule.
As I said I don't believe in your rule. What I tried to do is give
examples of superstimuli and show that in that case the race is for all
but the biggest racists not important. No matter what race you will
react the same. Think of it this way, if you see your SO with someone of
another race, will you think: 'it does not matter, hse doesn't fancy
members of that race'.
> You do have a point, however, if the rich black males
> outnumber rich white males, or white bodybuilders outnumber black
> bodybuilders in mixed populations, and if those qualifications are largely
> deemed desirable by the females.
I have a point if you or your SO has at any point fancied someone from
another race than yours.
>> If this is about the example of these birds, it is slightly more
>> complicated. I would definitely like to see data on female behaviour. If
>> a female with a black father prefers all black males and likewise for
>> chestnut breasts the case would be even stronger. But this is research,
>> within the boundaries of their protocol they did only check male
>> behaviour. I personally think the case is already strong enough, and I
>> hope that it generates money for more research to make the case
>> undeniable for even the greatest sceptic (at least those that look at
>> data, you never convince an anti-scientific creationist).
>
> Yes, it should be studied. But the conclusion that "study caught populations
> as they split into species" is premature and risky, IMO.
Can't get to the original article, thanks to the concept of IP in
science, but superficially it looks like one of those articles where
people do research and then add some DNA sequencing to get it published.
From the abstract alone I would not have been able to write the story
in the link. It seems they have a separate message for the peers and for
the general public.
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andrel <a_l### [at] hotmailcom> wrote:
> You are not able to interbreed with chimps and bonobos. Not only because
> you find them (probably) unattractive but also because our genes do not
> match. Somewhere along the line two chromosomes fused to one bigger one,
> so that we now have 23 pairs of them and the chimp still 24. There are
> also some other large reshuffelings of genes that will prevent mixed
> offspring. How the 46/48 chromosome hybrids ever were compatible is a
> thing that amazes me everytime, but that is something for another
> discussion.
But I guess this is exactly the point creationists will make.
In order for evolution to work with sexual reproduction to produce new species,
there *must* always be a phase where the two subspecies still *can* interpreed
(genetically), but are less *likely* to do so successfully, because either...
(a) they're genetically fully "compatible" with one another but separated into
different populations, or
(b) they're *slightly* less "compatible" with one another (e.g. having a higher
rate of birth defects, or invariably having offspring that have a minor genetic
disadvantage).
In case of a basic change of the genetic structure, like a different number of
chromosomes, this appears quite amazing, because obviously it cannot evolve
over time so (a) cannot play a role, and (b) seems unlikely due to the dramatic
proportions of the change.
BTW, the compatibility of the 46- and 48-chromosome population is very unlikely
to have been a problem: They would invariably have carried 23+24 chromosome
(i.e. 47 chromosome). They *must* have been compatible to some degree, because
the first mutation will in all likelyhood have affected only *one* chromosome
set, producing such a 47-chromosome individual.
This 47-chromosome individual must have proven successful enough to spread this
trait (with only 48-chromosome individuals available as partners, half of its
offspring would have had the regular set of 48 chromosomes, the other half 47
chromosomes, though there's reason to expect a higher percentage of
miscarriages or other complications in the 47-chromosome offspring), and its
offspring likewise, so that the 47-chromosome population could become large
enough to mate among themselves.
Only thus was it possible to produce the first 46-chromosome offspring (47/47
parents would have 25% 48-chromosome, 50% 47-chromosome and 25% 46-chromosome
offspring; again, the percentage of offspring actually born is likely to have
been different).
So intially the 47-chromosome population must have been comparatively
successful.
It is interesting then to think that this successful population would die out to
separate the 46- and 48-chromosome population from each other; but I guess this
can be explained by the acquisition of other mutations, some of which may have
been beneficial for one sub-population but slightly unfavorable for the other;
this would paved the way for other mutations causing the bearer to consider one
sub-population more attractive than the other, or looking more attractive to one
sub-population than to the other, which would start reducing genetic interchange
between the two populations; this in turn would make it more acceptable for a
mutation to be unfavorable for one group, as it would automatically be less
common in that one; again, this would increase the benefit of mutations to
reduce interbreeding. Ultimately, mutations prevalent in each group might be so
severe to the respective other, that it would be more beneficial - for each of
the groups - to render any 47-chromosome offspring infertile, and a mutation to
this effect would stick, finalizing the genetic barrier between the two groups.
Later mutations would round off this process by making it impossible for a
female to conceive from a member of the other group, so as not to waste any
energy at all on raising infertile offspring, and by making the groups
unnattractive to each other (maybe even particularly ugly) so as not to waste
any energy on even *trying* to interbreed in the first place.
The 47-chromosome population, being the most unstable one by having only 50%
offspring carrying the same trait, would in all likelyhood be unable to sustain
itself, declining in numbers as the main groups cease to interbreed. To develop
a separate population they would have had to accumulate mutations that would
separate their gene pool from that of both 46-chromosome and 48-chromosome
bearers - but this would have included half of their own offspring in each
generation, and therefore wasn't an option.
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clipka wrote:
> In case of a basic change of the genetic structure, like a different number of
> chromosomes, this appears quite amazing, because obviously it cannot evolve
> over time so (a) cannot play a role, and (b) seems unlikely due to the dramatic
> proportions of the change.
http://en.wikipedia.org/wiki/Down_syndrome
> So intially the 47-chromosome population must have been comparatively
> successful.
Or it's less hard to combine 48 with 46 than you might think. All the data
is there, including the tollermerines (or however you spell it) in the middle.
--
Darren New, San Diego CA, USA (PST)
"We'd like you to back-port all the changes in 2.0
back to version 1.0."
"We've done that already. We call it 2.0."
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On 19-7-2009 19:34, Darren New wrote:
> clipka wrote:
>> So intially the 47-chromosome population must have been comparatively
>> successful.
>
> Or it's less hard to combine 48 with 46 than you might think. All the
> data is there, including the tollermerines (or however you spell it) in
> the middle.
centromere?
I don't think everything is preserved, there may be a small part
missing, I assume that is more than just the telomeres (if that is the
other word you were looking for ;) ):
http://www.don-lindsay-archive.org/creation/translocation.html
apparently that was not crucial.
One reason to bring this point up is that the difference in chromosome
number is mentioned as one of the reasons why we can not interbreed with
chimps. If that is the case than you can not have different numbers of
chromosomes in various species. But you do, hence it must be more subtle
than that. When it first happens crossover during meiosis may be
impaired in the 47 chromosome individuals, but as long as the rest
matches, we can apparently get away with it.
Some random thoughs (that I am not sure if I tried those out here before)
The individual in which this translocation happened is undoubtedly one
of the ancestors of all men (as are the individuals in which the
inversions first appeared).* Slightly more speculative is my guess that
this or one of the inversions was the mutation that caused a form of
neotony in that ancestor. That would have resulted in a less strong but
more 'intelligent' individual. Which would have been a handicap in the
chimp and to a lesser extend the bonobo type of society for a male but a
huge advantage for a female. Hence: I think that particular ancestor was
a female (one of our Eves). It would be interesting to try to date those
mutations.
* if we have 30000 genes and we have 98% of our genes in common with the
two species of chimp than there are at least 300 ancestors common to all
humans since our split of the chimp line, and probably much more.
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On 19-7-2009 19:09, clipka wrote:
> andrel <a_l### [at] hotmailcom> wrote:
>> You are not able to interbreed with chimps and bonobos. Not only because
>> you find them (probably) unattractive but also because our genes do not
>> match. Somewhere along the line two chromosomes fused to one bigger one,
>> so that we now have 23 pairs of them and the chimp still 24. There are
>> also some other large reshuffelings of genes that will prevent mixed
>> offspring. How the 46/48 chromosome hybrids ever were compatible is a
>> thing that amazes me everytime, but that is something for another
>> discussion.
>
> But I guess this is exactly the point creationists will make.
>
> In order for evolution to work with sexual reproduction to produce new species,
> there *must* always be a phase where the two subspecies still *can* interpreed
> (genetically), but are less *likely* to do so successfully, because either...
>
> (a) they're genetically fully "compatible" with one another but separated into
> different populations, or
>
> (b) they're *slightly* less "compatible" with one another (e.g. having a higher
> rate of birth defects, or invariably having offspring that have a minor genetic
> disadvantage).
>
> In case of a basic change of the genetic structure, like a different number of
> chromosomes, this appears quite amazing, because obviously it cannot evolve
> over time so (a) cannot play a role, and (b) seems unlikely due to the dramatic
> proportions of the change.
As Darren pointed out, a different number of chromosomes may have severe
consequences when that is because one chromosome did not make it to the
next generation or if there is a duplication. (if there is down there
must also have been fertilized eggs with one chromosome 21 missing. I
think we can safely assume that is not compatible with life). Luckily in
our case it was a fusion of two chromosomes into one.
http://www.don-lindsay-archive.org/creation/translocation.html
>
> BTW, the compatibility of the 46- and 48-chromosome population is very unlikely
> to have been a problem: They would invariably have carried 23+24 chromosome
> (i.e. 47 chromosome). They *must* have been compatible to some degree, because
> the first mutation will in all likelyhood have affected only *one* chromosome
> set, producing such a 47-chromosome individual.
>
> This 47-chromosome individual must have proven successful enough to spread this
> trait (with only 48-chromosome individuals available as partners, half of its
> offspring would have had the regular set of 48 chromosomes, the other half 47
> chromosomes, though there's reason to expect a higher percentage of
> miscarriages or other complications in the 47-chromosome offspring), and its
> offspring likewise, so that the 47-chromosome population could become large
> enough to mate among themselves.
As incest is not common among chimps, we need at least two successful
generations of 47 chromosomes.
> Only thus was it possible to produce the first 46-chromosome offspring (47/47
> parents would have 25% 48-chromosome, 50% 47-chromosome and 25% 46-chromosome
> offspring; again, the percentage of offspring actually born is likely to have
> been different).
yes, they were probably different.
>
> So intially the 47-chromosome population must have been comparatively
> successful.
not necessarily. I also like to speculate on what happened, the problem
is a bit that we are reasoning from the fact that we know that in the
end humanity arose. Take also into account that the bottleneck between
chimps and humans is estimated at at least 1000 individuals, then it is
clear that interbreeding must have been possible for some time (and that
that bottle neck may not have been at this point in time).
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andrel wrote:
> As Darren pointed out, a different number of chromosomes may have severe
> consequences when that is because one chromosome did not make it to the
> next generation or if there is a duplication.
I don't know what point you thought I was trying to make. My point is that
organisms are extremely robust to screwed up genetics. You can give someone
and extra chromosome and they can still function.
I wouldn't want to gamble that someone with a different number of
chromosomes couldn't possibly have viable offspring. Not common, mind, but
impossible? I don't know enough to say.
> chimps and humans is estimated at at least 1000 individuals, then it is
I read recently that cheetahs don't reject organ transplants from other
cheetahs, and that looking at the chromosomes, one can tell that at one
point there were only 6 or 7 cheetahs in the world.
--
Darren New, San Diego CA, USA (PST)
"We'd like you to back-port all the changes in 2.0
back to version 1.0."
"We've done that already. We call it 2.0."
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andrel <a_l### [at] hotmailcom> wrote:
> * if we have 30000 genes and we have 98% of our genes in common with the
> two species of chimp than there are at least 300 ancestors common to all
> humans since our split of the chimp line, and probably much more.
According to http://www.genetics.org/cgi/content/full/156/1/297, it's 199
differences.
Furthermore, there are two basic fallacies in this argumentation:
* Given that the average number of mutations *per individual* is estimated at
about ~175 (!) in each generation (see aforementioned article - man, I confess
this sounds crazy!), all these 199 differences might have been acquired in just
one or two generations.
* It is not even necessary for all of these mutations to have occurred *after*
the split of the chimp/human line. Some may have been genetic differences that
were introduced earlier in the common ancestors of chimps and humans, but with
each variant prevailing in only one branch.
For instance, such a gene may have affected some aspect of visual appearance
which our common ancestors did not care much about, but which may have had a
beneficial side-effect for the new 46-chromosome group, therefore becoming more
and more frequent among it as the groups evolved apart; another mutation may
then have spread in the 48-chromosome group to consider this visual feature
unpleasant, further reducing the interbreeding rate and at the same time
beginning to extinguishing that feature in the 48-chromosome group.
So all we can really say about it all is that there is at least *one* common
ancestor to all humankind with any relation to the chimp/human separation: The
individual to be the first with 47 instead of 48 chromosomes.
Of course, given how many generations have passed since then, there is reason to
argue that virtually all early "46-chromosomians" that are ancestors to *any*
modern human can be expected to actually be ancestors of *all* modern humans -
even if some may not have left any trace in the modern human's gene pool, and
only very few (at *most* 199 :)) have passed on particular genes to *all*
modern humans.
Given this relationship, there's also reason to argue that the 199 genetic
differences between humans and chimps accumulated over time after all, and that
therefore indeed roughly 199 of our many common ancestors may have passed a part
of their genome on to *all* modern humans after all.
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clipka wrote:
> For instance, such a gene may have affected some aspect of visual appearance
> which our common ancestors did not care much about, but which may have had a
> beneficial side-effect for the new 46-chromosome group, therefore becoming more
> and more frequent among it as the groups evolved apart; another mutation may
> then have spread in the 48-chromosome group to consider this visual feature
> unpleasant, further reducing the interbreeding rate and at the same time
> beginning to extinguishing that feature in the 48-chromosome group.
>
This reminds me of the video I saw recently, and computer generated
extrapolation of the changes in morphology between the earliest human
ancestor skull, and a modern human, showing how each "tiny" change can,
over time, result in such a drastic one.
Mind, the music is kind of stupid, and the words they flash up once in a
while are kind of lame, but, otherwise:
http://www.youtube.com/watch?v=EcqA8wEljPM
Ah, they have a "class room" version without the lame stuff in it too:
http://www.youtube.com/watch?v=GrhYLvNeQd4
--
void main () {
If Schrödingers_cat is alive or version > 98 {
if version = "Vista" {
call slow_by_half();
call DRM_everything();
}
call functional_code();
}
else
call crash_windows();
}
<A HREF='http://www.daz3d.com/index.php?refid=16130551'>Get 3D Models,
3D Content, and 3D Software at DAZ3D!</A>
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John VanSickle wrote:
> Darren New wrote:
>> Well, so much for the old "we've never seen it happen, so it can't."
>>
>>
http://www.geneticarchaeology.com/research/Study_catches_2_bird_populations_as_they_split_into_separate_species.asp
>
>
> We haven't seen it happen yet.
Actually we have, dozens of times. This is just an example of "on the cusp."
But that's OK. :-)
--
Darren New, San Diego CA, USA (PST)
"We'd like you to back-port all the changes in 2.0
back to version 1.0."
"We've done that already. We call it 2.0."
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Darren New <dne### [at] sanrrcom> wrote:
> Or it's less hard to combine 48 with 46 than you might think. All the data
> is there, including the tollermerines (or however you spell it) in the middle.
Just happened to stumble across the Wikipedia articles on mules and hinnys
(citing the latter here):
"A donkey has 62 chromosomes, whereas a horse has 64. Hinnies, being hybrids of
those two species, have 63 chromosomes and are sterile."
But later on the article reveals that this is an oversimplification:
"Female mules have been known to produce offspring when mated to a purebred
horse or donkey, though this is extremely uncommon."
Duh. Didn't know that horses and donkeys have different numbers of chromosomes,
too (then again, it was news to me as well that chimps and humans have).
So this makes me think that...
- mutations changing the number of chromosomes don't seem to be as uncommon as I
had thought
- with mules and hinnys being perfectly viable and typically not showing any
other defects, and even *not always* being sterile, this gives rise to the
assumption that having an odd number of chromosomes is an absolutely
non-dramatic mutation as such (why should *only* the reproductive system show
issues? and why not always?), and that the sterility is instead imposed by
other genetic mechanisms "designed" (by evolution) to separate the two gene
pools.
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clipka wrote:
> "Female mules have been known to produce offspring when mated to a purebred
> horse or donkey, though this is extremely uncommon."
Yes. This is another one of those "on the cusp of becoming two species." It
really isn't as uncommon as people think.
--
Darren New, San Diego CA, USA (PST)
"We'd like you to back-port all the changes in 2.0
back to version 1.0."
"We've done that already. We call it 2.0."
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On 21-7-2009 18:15, clipka wrote:
> Darren New <dne### [at] sanrrcom> wrote:
>> Or it's less hard to combine 48 with 46 than you might think. All the data
>> is there, including the tollermerines (or however you spell it) in the middle.
>
> Just happened to stumble across the Wikipedia articles on mules and hinnys
> (citing the latter here):
>
> "A donkey has 62 chromosomes, whereas a horse has 64. Hinnies, being hybrids of
> those two species, have 63 chromosomes and are sterile."
>
> But later on the article reveals that this is an oversimplification:
>
> "Female mules have been known to produce offspring when mated to a purebred
> horse or donkey, though this is extremely uncommon."
>
>
> Duh. Didn't know that horses and donkeys have different numbers of chromosomes,
> too (then again, it was news to me as well that chimps and humans have).
>
> So this makes me think that...
>
> - mutations changing the number of chromosomes don't seem to be as uncommon as I
> had thought
http://en.wikipedia.org/wiki/List_of_number_of_chromosomes_of_various_organisms
is hard to explain otherwise.
> - with mules and hinnys being perfectly viable and typically not showing any
> other defects, and even *not always* being sterile, this gives rise to the
> assumption that having an odd number of chromosomes is an absolutely
> non-dramatic mutation as such (why should *only* the reproductive system show
> issues? and why not always?), and that the sterility is instead imposed by
> other genetic mechanisms "designed" (by evolution) to separate the two gene
> pools.
I guess how dramatic it is, is variable. For those that we know of it is
not an extreme problem. Where 'know of' is the important bit. If the
translocation that resulted in our chromosome 2 would not have been
viable or have been sterile, we would not have known.
You know of trisomy 21 because it is common, viable, and recognizable.
According to wikipedia trisomy 16 is actual the most common, guess why
you have never heard of it.
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andrel <a_l### [at] hotmailcom> wrote:
> > - mutations changing the number of chromosomes don't seem to be as uncommon as I
> > had thought
>
> http://en.wikipedia.org/wiki/List_of_number_of_chromosomes_of_various_organisms
> is hard to explain otherwise.
The Raccoon Dog seems particularly interesting in that respect; anyone knows
whether the subspecies can interbreed?
Hedgehogs (African vs. Woodland) likewise.
Swamp Wallabys and Echidnas have interesting chromosome configurations, too.
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On 20-7-2009 0:46, clipka wrote:
> andrel <a_l### [at] hotmailcom> wrote:
>> * if we have 30000 genes and we have 98% of our genes in common with the
>> two species of chimp than there are at least 300 ancestors common to all
>> humans since our split of the chimp line, and probably much more.
>
> According to http://www.genetics.org/cgi/content/full/156/1/297, it's 199
> differences.
That is 199 in the area they searched, which was only about 11000
basepairs. The total amount they still estimate at 1.2% (and
http://www.gate.net/~rwms/EvoEvidence.html at 1.6 and 1.7%) which means
that the actual number of differences between you and that chimp in the
zoo is more in the 100 million ballpark.
> Furthermore, there are two basic fallacies in this argumentation:
>
> * Given that the average number of mutations *per individual* is estimated at
> about ~175 (!) in each generation (see aforementioned article - man, I confess
> this sounds crazy!), all these 199 differences might have been acquired in just
> one or two generations.
>
> * It is not even necessary for all of these mutations to have occurred *after*
> the split of the chimp/human line. Some may have been genetic differences that
> were introduced earlier in the common ancestors of chimps and humans, but with
> each variant prevailing in only one branch.
That is true. That is even true for the number that I was looking for:
the number of mutations that are present in all humans and not in either
chimp species. My initial estimate (above) is clearly nonsense, I admit,
but perhaps someone has a better idea.
> For instance, such a gene may have affected some aspect of visual appearance
> which our common ancestors did not care much about, but which may have had a
> beneficial side-effect for the new 46-chromosome group, therefore becoming more
> and more frequent among it as the groups evolved apart; another mutation may
> then have spread in the 48-chromosome group to consider this visual feature
> unpleasant, further reducing the interbreeding rate and at the same time
> beginning to extinguishing that feature in the 48-chromosome group.
>
>
> So all we can really say about it all is that there is at least *one* common
> ancestor to all humankind with any relation to the chimp/human separation: The
> individual to be the first with 47 instead of 48 chromosomes.
I would vote for the inversions too, although they can have occurred
simultaneously. Yet, I think that is not likely.
There is also that thing that if we would biotechnically separate
chromosome 2 again along the original lines, would the resulting
offspring be a person or an animal, human or chimp?
Ethically not permissible of course, but I find the idea of generating a
line of links between us and our chimp brothers quite appealing. If only
to annoy the pope and the born again Christians. Though perhaps the
possibility of creating intermediate chimans (humps?) would be enough to
have them think again.
Reality check: would my ethics change if there was an intermediate
(sub)species between humans an chimps? Checking... a bit, but no major
rebuilding necessary.
How about yours (to the group at large, or should that be a separate
thread?)?
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On 22-7-2009 23:09, clipka wrote:
> andrel <a_l### [at] hotmailcom> wrote:
>>> - mutations changing the number of chromosomes don't seem to be as uncommon as I
>>> had thought
>> http://en.wikipedia.org/wiki/List_of_number_of_chromosomes_of_various_organisms
>> is hard to explain otherwise.
>
> The Raccoon Dog seems particularly interesting in that respect; anyone knows
> whether the subspecies can interbreed?
>
> Hedgehogs (African vs. Woodland) likewise.
>
> Swamp Wallabys and Echidnas have interesting chromosome configurations, too.
Genetics and male/female seems to be much much more complicated (and
interesting) than what they tough us as school.
Another think I did not know: Broccoli, cabbage, kale, kohlrabi,
brussels sprouts, and cauliflower are all the same species
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andrel wrote:
> Reality check: would my ethics change if there was an intermediate
> (sub)species between humans an chimps?
You mean like Neanderthal? Otherwise, you're going to have to define
"subspecies". :-)
--
Darren New, San Diego CA, USA (PST)
"We'd like you to back-port all the changes in 2.0
back to version 1.0."
"We've done that already. We call it 2.0."
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On 22-7-2009 23:43, Darren New wrote:
> andrel wrote:
>> Reality check: would my ethics change if there was an intermediate
>> (sub)species between humans an chimps?
>
> You mean like Neanderthal? Otherwise, you're going to have to define
> "subspecies". :-)
>
That was meant in the context of reversing some of the mutations that
separate us from the chimps (or retrofitting our mutations in them*). At
some point the 'result' will probably still be able to interbreed with
humans but be a clear subspecies with different characteristics. Halfway
down the process I expect that there will be a true species that can not
interbreed with us, bonobos, or chimps. Unlikely, but possibly, it would
be able to mate with all, which would, I think, technically mean we
would all become subspecies of this human/chimp complex. So that is why
I put '(sub)' in parentheses, because I don't know. I wasn't referring
to Neanderthal or forensis or any other humanoid that has existed.
* you can do experiments on chimps. I think such a breeding experiment
would not even be illegal, contrary to the route starting with a human.
Though somewhere along the line you would hit a legal wall, when the
chimp becomes too human. Can we predict in advance when that will be? If
not, can we afterwards decide that we did cross the line?
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andrel wrote:
> On 22-7-2009 23:43, Darren New wrote:
>> andrel wrote:
>>> Reality check: would my ethics change if there was an intermediate
>>> (sub)species between humans an chimps?
>>
>> You mean like Neanderthal? Otherwise, you're going to have to define
>> "subspecies". :-)
>>
> That was meant in the context of reversing some of the mutations that
> separate us from the chimps (or retrofitting our mutations in them*).
I understand that. Aren't neanderthals between us and the common ancestor of
us and chimps? I.e., didn't cro magnon descend from neanderthal? I guess I
should look that up myself, but...
--
Darren New, San Diego CA, USA (PST)
"We'd like you to back-port all the changes in 2.0
back to version 1.0."
"We've done that already. We call it 2.0."
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Darren New wrote:
> John VanSickle wrote:
>> Darren New wrote:
>>> Well, so much for the old "we've never seen it happen, so it can't."
>>>
>>>
http://www.geneticarchaeology.com/research/Study_catches_2_bird_populations_as_they_split_into_separate_species.asp
>>
>>
>>
>> We haven't seen it happen yet.
>
> Actually we have, dozens of times. This is just an example of "on the
> cusp." But that's OK. :-)
I notice how much of the reasoning here treats things that makes sense
and don't contradict the evidence as if they had actually been observed,
when in fact they have not. For instance, this idea of this being a
cusp. Even if it were, it could not be truly counted as observed until
it has actually passed, in which case we would no longer be "on the cusp."
Regards,
John
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John VanSickle wrote:
> Even if it were, it could not be truly counted as observed until
> it has actually passed, in which case we would no longer be "on the cusp."
Speciation has been observed happening in the wild as well as induced by
people. Based on the induced speciation, people know at least one mechanism
by which it comes about. These birds are subject to one of those mechanisms
right now, according to the researchers.
Of course, maybe it won't happen. But if you're in the final innings of a
World Series baseball game and you're ahead by several runs, it's fair to
say you're "on the cusp" of winning, even if it turns out you lose.
I.e., it's assumed they're "on the cusp", yes, but that's always true when
you use that phrase, since it's predicting the future.
Given that, the article doesn't say "on the cusp".
--
Darren New, San Diego CA, USA (PST)
"We'd like you to back-port all the changes in 2.0
back to version 1.0."
"We've done that already. We call it 2.0."
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On 23-7-2009 1:11, Darren New wrote:
> andrel wrote:
>> On 22-7-2009 23:43, Darren New wrote:
>>> andrel wrote:
>>>> Reality check: would my ethics change if there was an intermediate
>>>> (sub)species between humans an chimps?
>>>
>>> You mean like Neanderthal? Otherwise, you're going to have to define
>>> "subspecies". :-)
>>>
>> That was meant in the context of reversing some of the mutations that
>> separate us from the chimps (or retrofitting our mutations in them*).
>
> I understand that. Aren't neanderthals between us and the common
> ancestor of us and chimps? I.e., didn't cro magnon descend from
> neanderthal? I guess I should look that up myself, but...
>
There is no easy way to know which mutations occured later, so a
complete rollback is impossible. Besides I suggested to start with the
biggest changes (some of them presumably among the oldest) first, so
that the result of that operation would not result in a species that had
ever existed. If cro magnon or neaderthal were a dead end, you can not
reach them even if you knew exactly in what order the mutations arose
starting from our common ancestor until modern humans.
But you knew that.
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Darren New <dne### [at] sanrrcom> wrote:
> I understand that. Aren't neanderthals between us and the common ancestor of
> us and chimps? I.e., didn't cro magnon descend from neanderthal? I guess I
> should look that up myself, but...
Nope.
In the last decades, research found clear evidence that neanderthalensis and cro
magnon developed independently from a common ancestor.
Recent research adds that although neanderthalensis and cro magnon have been
living side by side in Europe for quite some time, they did not interbreed (at
least not successfully in the long run); neanderthalensis did not leave any
trace in the genome of modern human (and it most likely wasn't for a lack of
occasional attempts).
Thus neanderthalensis - although most likely having been human enough to go
unnoticed in a modern city, and maybe also intellectually evolved enough to get
along ok in modern times - turns out to be just the last of many separate
species of homo erectus to be out-evolved by the direct ancestors of modern
human.
Looks like The Intelligent Designer did a lot of experimenting before settling
on the final design for Adam...
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