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| Lee Olsen... |
 Posted: Fri Oct 30, 2009 6:02 pm |
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| caldervangogh at (no spam) gmail.com... |
| Posted: Sat Oct 31, 2009 6:11 am |
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On Oct 30, 11:02 pm, Lee Olsen <paleoc... at (no spam) hotmail.com> wrote:
[quote]http://www.nytimes.com/2009/10/27/health/27well.html
[/quote]
That may be true now, or in recent past
http://tinyurl.com/ygquqdk
but Ardi makes it difficult to push this back before 4.4 mya.
Yes, h.e. at 1.8 mya.
Yes now, perhaps, with the flat soles, training, etc. (although note
that the injuries have gone up with other soles)
but how does this, endurance running, or persistance hunting, relate
to our becoming bipedal at about 6 mya?
regards
calder |
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| Lee Olsen... |
| Posted: Sat Oct 31, 2009 9:43 am |
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On Oct 31, 9:11 am, "caldervang... at (no spam) gmail.com"
<caldervang... at (no spam) gmail.com> wrote:
[quote]
but how does this, endurance running, or persistance hunting, relate
to our becoming bipedal at about 6 mya?
[/quote]
As Craig Stanford puts it, something like a gibbon, in the trees, gave
apes
a "headstart program" to select upon. Then as the climate dried out
and trees
became further apart, selection went further in the bipedal direction.
http://tinyurl.com/38osfr
then
http://www.youtube.com/watch?v=hlzRCHASvsw
Where trees didn't go mostly away, chimps evolved. The Laetoli
tracks prove by 3.5 mya something was already walking straight lines
(which means open country) and probably following the herd
migrations.
Gerrit posted a great photo ( I lost the URL) showing the straight-
line
migration tracks, which is what the ridges at Laetoli are thought to
represent.
By 2.5 mya tools are found in the same beds with ostriches.
By 1.8 mya there are the foot prints that look exactly like ours
today.
Here is a better paper than the one above:
http://www.fas.harvard.edu/~skeleton/pdfs/2007c.pdf
[quote]
regards
calder[/quote] |
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| caldervangogh at (no spam) gmail.com... |
| Posted: Mon Nov 02, 2009 5:01 pm |
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Guest
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On Oct 31, 2:43 pm, Lee Olsen <paleoc... at (no spam) hotmail.com> wrote:
[quote]On Oct 31, 9:11 am, "caldervang... at (no spam) gmail.com"
caldervang... at (no spam) gmail.com> wrote:
but how does this, endurance running, or persistance hunting, relate
to our becoming bipedal at about 6 mya?
As Craig Stanford puts it, something like a gibbon, in the trees, gave
apes
a "headstart program" to select upon. Then as the climate dried out
and trees
became further apart, selection went further in the bipedal direction.http://tinyurl.com/38osfr
thenhttp://www.youtube.com/watch?v=hlzRCHASvsw
Where trees didn't go mostly away, chimps evolved. The Laetoli
tracks prove by 3.5 mya something was already walking straight lines
(which means open country) and probably following the herd
migrations.
Gerrit posted a great photo ( I lost the URL) showing the straight-
line
migration tracks, which is what the ridges at Laetoli are thought to
represent.
By 2.5 mya tools are found in the same beds with ostriches.
By 1.8 mya there are the foot prints that look exactly like ours
today.
Here is a better paper than the one above:http://www.fas.harvard.edu/~skeleton/pdfs/2007c.pdf
regards
calder- Hide quoted text -
- Show quoted text -
[/quote]
I am skeptical of the "bipedalism started in the trees" scenario
because of the way that humans and some of the other great apes use
their leg muscles. They are not analagous. Some of this was in the
"Red Ape Stroll" article and all of it was in another article on
Science News that I don't have access to right now. (my subscription
is out.. will probably renew soon.)
Rich posted a version of the Red Ape Stroll.
Anyway, it seems that our muscles and nerves respond in exactly the
opposite manner to those creatures that walk bipedally on limbs. This
would mean we would evolve one type of bipedalism, abandon it, and
then evolve another. In a mere 6 million years. (or really 3
million, since "Lucy" was already using straight-toe walking.)
Running is, IMHO, a contenter for the "bipedalism prize" but I just
don't yet see my way clear thru the obstacles.
regards
calder |
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| Lee Olsen... |
| Posted: Tue Nov 03, 2009 3:44 am |
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On Nov 2, 7:01 pm, "caldervang... at (no spam) gmail.com" <caldervang... at (no spam) gmail.com>
wrote:
[quote]On Oct 31, 2:43 pm, Lee Olsen <paleoc... at (no spam) hotmail.com> wrote:
On Oct 31, 9:11 am, "caldervang... at (no spam) gmail.com"
caldervang... at (no spam) gmail.com> wrote:
but how does this, endurance running, or persistance hunting, relate
to our becoming bipedal at about 6 mya?
As Craig Stanford puts it, something like a gibbon, in the trees, gave
apes
a "headstart program" to select upon. Then as the climate dried out
and trees
became further apart, selection went further in the bipedal direction.http://tinyurl.com/38osfr
thenhttp://www.youtube.com/watch?v=hlzRCHASvsw
Where trees didn't go mostly away, chimps evolved. The Laetoli
tracks prove by 3.5 mya something was already walking straight lines
(which means open country) and probably following the herd
migrations.
Gerrit posted a great photo ( I lost the URL) showing the straight-
line
migration tracks, which is what the ridges at Laetoli are thought to
represent.
By 2.5 mya tools are found in the same beds with ostriches.
By 1.8 mya there are the foot prints that look exactly like ours
today.
Here is a better paper than the one above:http://www.fas.harvard.edu/~skeleton/pdfs/2007c.pdf
regards
calder- Hide quoted text -
- Show quoted text -
I am skeptical of the "bipedalism started in the trees" scenario
because of the way that humans and some of the other great apes use
their leg muscles.
[/quote]
Yes, *now*...you are not taking into account their separate
evolutionary trajectories.
..
There is no reason at all to believe any of the apes today (gibbons,
pan,
etc.) are a mirror image of the LCA to all of us.
[quote] They are not analagous.
[/quote]
No one said they were. But it is what is most parsimonious and that is
this guy:
http://tinyurl.com/38osfr
Of course he is not us or a direct ancestor.
[quote] Some of this was in the
"Red Ape Stroll" article and all of it was in another article on
Science News that I don't have access to right now. (my subscription
is out.. will probably renew soon.)
Rich posted a version of the Red Ape Stroll.
Anyway, it seems that our muscles and nerves respond in exactly the
opposite manner to those creatures that walk bipedally on limbs.
[/quote]
*now*.... please don't jump from 20 mya to now without considering all
the changes
between monkeys and the other apes. This thinking also applies to the
differences between A'piths. Some overlap in time, they all can't be
our direct ancestors.
[quote]this would mean we would evolve one type of bipedalism, abandon it, and
then evolve another. In a mere 6 million years. (or really 3
million, since "Lucy" was already using straight-toe walking.)
[/quote]
Nope, what you can't see is what's missing. How do you account for
the fact that Robusts and T-boy were sharing the same area? Both
walked
upright, so what?
And to go back just a bit further in time....Lucy may be a very close
cousin,
but we know she did not lead directly to us, anymore than Neandertals
led
directy to us.
[quote]
Running is, IMHO, a contenter for the "bipedalism prize" but I just
[/quote]
No, some type of runnining led to persistent running, by that time
what Lucy,
chimps, gibbons were doing is out of the loop and irrelevant, they
were
doing their own thing. Lemurs are a good example too. Only some lemurs
do a pathetic-type running between trees, they *all* don't do it. It
would only be
out of that group that could lead to endurant bipedalism 20 million
years from now
if the environmental circumstances where right. If not, they will
simply stay in
the trees and go extinct. I know it isn't that simple, just giving
you the general
idea.
[quote]don't yet see my way clear thru the obstacles.
[/quote]
Please advise on how you account for the lack of a tail between the
great apes
and the monkeys. What is the reason for that change in your mind?
[quote]regards
calder- Hide quoted text -
- Show quoted text -[/quote] |
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| caldervangogh at (no spam) gmail.com... |
| Posted: Tue Nov 03, 2009 3:39 pm |
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On Nov 3, 8:44 am, Lee Olsen <paleoc... at (no spam) hotmail.com> wrote:
[quote]On Nov 2, 7:01 pm, "caldervang... at (no spam) gmail.com" <caldervang... at (no spam) gmail.com
wrote:
On Oct 31, 2:43 pm, Lee Olsen <paleoc... at (no spam) hotmail.com> wrote:
On Oct 31, 9:11 am, "caldervang... at (no spam) gmail.com"
caldervang... at (no spam) gmail.com> wrote:
but how does this, endurance running, or persistance hunting, relate
to our becoming bipedal at about 6 mya?
As Craig Stanford puts it, something like a gibbon, in the trees, gave
apes
a "headstart program" to select upon. Then as the climate dried out
and trees
became further apart, selection went further in the bipedal direction..http://tinyurl.com/38osfr
thenhttp://www.youtube.com/watch?v=hlzRCHASvsw
Where trees didn't go mostly away, chimps evolved. The Laetoli
tracks prove by 3.5 mya something was already walking straight lines
(which means open country) and probably following the herd
migrations.
Gerrit posted a great photo ( I lost the URL) showing the straight-
line
migration tracks, which is what the ridges at Laetoli are thought to
represent.
By 2.5 mya tools are found in the same beds with ostriches.
By 1.8 mya there are the foot prints that look exactly like ours
today.
Here is a better paper than the one above:http://www.fas.harvard.edu/~skeleton/pdfs/2007c.pdf
regards
calder- Hide quoted text -
- Show quoted text -
I am skeptical of the "bipedalism started in the trees" scenario
because of the way that humans and some of the other great apes use
their leg muscles.
Yes, *now*...you are not taking into account their separate
evolutionary trajectories.
.
There is no reason at all to believe any of the apes today (gibbons,
pan,
etc.) are a mirror image of the LCA to all of us.
[/quote]
Well, of course, and that is the lesson that Ardi proved.
Briefly, the situation is like two people jumping on a trampoline.
When one "lands" the other is "rocketed" up, in sort of a action-
reaction sequence. The Orang, when it is moving bipedally on a limb,
uses his/her "rocket" muscles, and the human, when walking in a
similar fashion on a springy surface, uses the opposite muscles, the
"landing" ones....
Therefore, if (*IF*) bipedal walking evolved in humans for the reason
of walking on limbs, then it would be parallel evolution with the
other apes/great apes that walk on limbs, yes? So, we would have
evolved our "rocket" muscles for use in walking on land upright. Our
evolution plateau for this feature... bipedal movement... could have
occured 6 mya or 20 mya just the same... and would have to un-evolve
the "rocket" muscles in favor of the landing ones when transitioning
out of the trees. I am thinking specifically of the parsimony of this
problem.
[quote]
They are not analagous.
No one said they were. But it is what is most parsimonious and that is
this guy:http://tinyurl.com/38osfr
Of course he is not us or a direct ancestor.
Some of this was in the
"Red Ape Stroll" article and all of it was in another article on
Science News that I don't have access to right now. (my subscription
is out.. will probably renew soon.)
Rich posted a version of the Red Ape Stroll.
Anyway, it seems that our muscles and nerves respond in exactly the
opposite manner to those creatures that walk bipedally on limbs.
*now*.... please don't jump from 20 mya to now without considering all
the changes
between monkeys and the other apes. This thinking also applies to the
differences between A'piths. Some overlap in time, they all can't be
our direct ancestors.
[/quote]
Having done genealogy for 25 years, I can assure you that it is very
difficult to prove that any particular individual just a few
generations back is your actual ancestor. DNA has helped, but even
that is not accurate except to 8 generations ago. Point is, no, Ardi
or Lucy is probably not our direct ancestor, but definitely seem to be
in our clade.
[quote]
this would mean we would evolve one type of bipedalism, abandon it, and
then evolve another. In a mere 6 million years. (or really 3
million, since "Lucy" was already using straight-toe walking.)
Nope, what you can't see is what's missing. How do you account for
the fact that Robusts and T-boy were sharing the same area? Both
walked
upright, so what?
And to go back just a bit further in time....Lucy may be a very close
cousin,
but we know she did not lead directly to us, anymore than Neandertals
led
directy to us.
Running is, IMHO, a contenter for the "bipedalism prize" but I just
No, some type of runnining led to persistent running, by that time
what Lucy,
chimps, gibbons were doing is out of the loop and irrelevant, they
were
doing their own thing.
[/quote]
I thought you WERE proposing running as a reason that we evolved
bipedalism? Therefore, I suppose, we have no disagreement, because I
am full-on-board with running being an early and important adaptation
for homo.
[quote]Lemurs are a good example too. Only some lemurs
do a pathetic-type running between trees, they *all* don't do it. It
would only be
out of that group that could lead to endurant bipedalism 20 million
years from now
if the environmental circumstances where right. If not, they will
simply stay in
the trees and go extinct. I know it isn't that simple, just giving
you the general
idea.
don't yet see my way clear thru the obstacles.
Please advise on how you account for the lack of a tail between the
great apes
and the monkeys. What is the reason for that change in your mind?
[/quote]
There are a lot of papers on that one, and it seems to be balance
related in arboreal movement.
By the way, on my way to looking up other things, I did read through
this rather interesting abstract about the foot being great for
bipedal STANDING:
http://linkinghub.elsevier.com/retrieve/pii/S0021929004001265
Abstract
The ratio of the power arm (the distance from the heel to the
talocrural joint) to the load arm (that from the talocrural joint to
the distal head of the metatarsals), or RPL, differs markedly between
the human and ape foot. The arches are relatively higher in the human
foot in comparison with those in apes. This study evaluates the effect
of these two differences on biomechanical effectiveness during bipedal
standing, estimating the forces acting across the talocrural and
tarsometatarsal joints, and attempts to identify which type of foot is
optimal for bipedal standing. A simple model of the foot
musculoskeletal system was built to represent the geometric and force
relationships in the foot during bipedal standing, and measurements
for a variety of human and ape feet applied. The results show that:
(1) an RPL of around 40% (as is the case in the human foot) minimizes
required muscle force at the talocrural joint; (2) the presence of an
high arch in the human foot reduces forces in the plantar musculature
and aponeurosis; and (3) the human foot has a lower total of force in
joints and muscles than do the ape feet. These results indicate that
the proportions of the human foot, and the height of the medial arch
are indeed better optimized for bipedal standing than those of apes,
further suggesting that their current state is to some extent the
product of positive selection for enhanced bipedal standing during the
evolution of the foot.
Analysis of the human and ape foot during bipedal standing with
implications for the evolution of the foot
Journal of Biomechanics, Volume 37, Issue 12, Pages 1831-1836
W. Wang, R. Crompton
[quote]
regards
calder- Hide quoted text -
- Show quoted text -- Hide quoted text -
- Show quoted text -- Hide quoted text -
- Show quoted text -[/quote] |
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| Lee Olsen... |
| Posted: Tue Nov 03, 2009 5:23 pm |
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On Nov 3, 5:39 pm, "caldervang... at (no spam) gmail.com" <caldervang... at (no spam) gmail.com>
wrote:
[quote]
Having done genealogy for 25 years, I can assure you that it is very
difficult to prove that any particular individual just a few
generations back is your actual ancestor.
DNA has helped, but even
that is not accurate except to 8 generations ago. Point is, no, Ardi
or Lucy is probably not our direct ancestor, but definitely seem to be
in our clade.
[/quote]
Yep, pretty bushy tree.
[quote]
I thought you WERE proposing running as a reason that we evolved
bipedalism?
[/quote]
Not running as we know it, sloppy running as the gibbon is doing
getting
away from the dog and I'll bet they still have a long way to go.
Someone ought to take their trees away and see what happens in a few
million years.
http://tinyurl.com/ylqqknv
Some lemurs have got the idea, but their tail is probably going to be
a hindrance. Take their trees away and they simply may end up
a funny looking baboon.
[quote] Therefore, I suppose, we have no disagreement, because I
am full-on-board with running being an early and important adaptation
for homo.
[/quote]
[quote]
Please advise on how you account for the lack of a tail between the
great apes
and the monkeys. What is the reason for that change in your mind?
There are a lot of papers on that one, and it seems to be balance
related in arboreal movement.
[/quote]
I agree with that.
[quote]
By the way, on my way to looking up other things, I did read through
this rather interesting abstract about the foot being great for
bipedal STANDING:
http://linkinghub.elsevier.com/retrieve/pii/S0021929004001265
Abstract
The ratio of the power arm (the distance from the heel to the
talocrural joint) to the load arm (that from the talocrural joint to
the distal head of the metatarsals), or RPL, differs markedly between
the human and ape foot. The arches are relatively higher in the human
foot in comparison with those in apes. This study evaluates the effect
of these two differences on biomechanical effectiveness during bipedal
standing, estimating the forces acting across the talocrural and
tarsometatarsal joints, and attempts to identify which type of foot is
optimal for bipedal standing. A simple model of the foot
musculoskeletal system was built to represent the geometric and force
relationships in the foot during bipedal standing, and measurements
for a variety of human and ape feet applied. The results show that:
(1) an RPL of around 40% (as is the case in the human foot) minimizes
required muscle force at the talocrural joint; (2) the presence of an
high arch in the human foot reduces forces in the plantar musculature
and aponeurosis; and (3) the human foot has a lower total of force in
joints and muscles than do the ape feet. These results indicate that
the proportions of the human foot, and the height of the medial arch
are indeed better optimized for bipedal standing than those of apes,
further suggesting that their current state is to some extent the
product of positive selection for enhanced bipedal standing during the
evolution of the foot.
Analysis of the human and ape foot during bipedal standing with
implications for the evolution of the foot
Journal of Biomechanics, Volume 37, Issue 12, Pages 1831-1836
W. Wang, R. Crompton
[/quote]
OK, but the foot is connected to the legs that are connected to the
butt muscles. If we were just standing around all day or even
walking,
we wouldn't have evolved an ass bigger than a chimps. |
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| rmacfarl... |
| Posted: Wed Nov 04, 2009 2:28 am |
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<caldervangogh at (no spam) gmail.com> wrote in message
news:ff8936c0-bd8c-4ade-bdaa-b0190b076164 at (no spam) g23g2000yqh.googlegroups.com...
On Nov 3, 8:44 am, Lee Olsen <paleoc... at (no spam) hotmail.com> wrote:
[quote]On Nov 2, 7:01 pm, "caldervang... at (no spam) gmail.com"
caldervang... at (no spam) gmail.com
wrote:
....
Having done genealogy for 25 years, I can assure you that it is
very
difficult to prove that any particular individual just a few
generations back is your actual ancestor. DNA has helped, but
even
that is not accurate except to 8 generations ago. Point is,
no, Ardi
or Lucy is probably not our direct ancestor, but definitely
seem to be
in our clade.
[/quote]
Just a comment on this point... If you could successfully track
all of the connections & cross-connections back within your
family tree, you would be descended from nearly anybody you can
name. Hence mtDNA Eve.
I once read that from memory Mary Queen of Scots appears
something like 30+ times in Prince Charles' family tree. It's a
glib response to say the Royal Family are inbred - they are, but
no more than anyone living in a relatively closed society. Most
Englishmen of more than 50 years of age are very likely just as
inbred, but they can't trace their genealogy with as much
certainty as the PoW.
Whether Ardi or Lucy were our ancestors is more problematic. It
depends on whether their species evolved into early Homo or not -
which now seems unlikely for Afarensis at least. If they did, &
if Ardi &/or Lucy had progeny, it is quite conceivable that they
contributed directly to your and my family tree. You can be quite
sure though that the Taung baby & the Turkana boy didn't - they
died to young to leave descendants...
Ross Macfarlane |
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| Lee Olsen... |
| Posted: Wed Nov 04, 2009 3:42 am |
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On Nov 3, 11:28 pm, "rmacfarl" <rmacf... at (no spam) alphalink.com.au> wrote:
[quote]
Whether Ardi or Lucy were our ancestors is more problematic. It
depends on whether their species evolved into early Homo or not -
[/quote]
Right, I agree. It is all at the species level in the Pleistocene and
at the
5th cousin level now. |
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