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| Marc Verhaegen... |
 Posted: Tue Aug 25, 2009 5:23 pm |
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Guest
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Independent evolution of knuckle-walking in African apes shows that humans
did not evolve from a knuckle-walking ancestor
TL Kivell & D Schmitt 2009 PNAS 106:14241-6
Despite decades of debate, it remains unclear whether human bipedalism
evolved from a terrestrial knuckle-walking ancestor or from a more
generalized, arboreal ape ancestor. Proponents of the knuckle-walking
hypothesis focused on the wrist and hand to find morphological evidence of
this behavior in the human fossil record. These studies, however, have not
examined variation or development of purported knuckle-walking features in
apes or other primates, data that are critical to resolution of this
long-standing debate. Here we present novel data on the frequency and
development of putative knuckle-walking features of the wrist in apes and
monkeys. We use these data to test the hypothesis that all knuckle-walking
apes share similar anatomical features and that these features can be used
to reliably infer locomotor behavior in our extinct ancestors. Contrary to
previous expectations, features long-assumed to indicate knuckle-walking
behavior are not found in all African apes, show different developmental
patterns across species, and are found in nonknuckle-walking primates as
well. However, variation among African ape wrist morphology can be clearly
explained if we accept the likely independent evolution of 2 fundamentally
different biomechanical modes of knuckle-walking: an extended wrist posture
in an arboreal environment (Pan) versus a neutral, columnar hand posture in
a terrestrial environment (Gorilla). The presence of purported
knuckle-walking features in the hominin wrist can thus be viewed as evidence
of arboreality, not terrestriality, and provide evidence that human
bipedalism evolved from a more arboreal ancestor occupying the ecological
niche common to all living apes. |
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| mclark... |
| Posted: Tue Aug 25, 2009 5:23 pm |
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Guest
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On Aug 25, 6:23 pm, Marc Verhaegen <m_verhae... at (no spam) skynet.be> wrote:
[quote:ae82763c51]Independent evolution of knuckle-walking in African apes shows that humans
did not evolve from a knuckle-walking ancestor
TL Kivell & D Schmitt 2009 PNAS 106:14241-6
Despite decades of debate, it remains unclear whether human bipedalism
evolved from a terrestrial knuckle-walking ancestor or from a more
generalized, arboreal ape ancestor. Proponents of the knuckle-walking
hypothesis focused on the wrist and hand to find morphological evidence of
this behavior in the human fossil record. These studies, however, have not
examined variation or development of purported knuckle-walking features in
apes or other primates, data that are critical to resolution of this
long-standing debate. Here we present novel data on the frequency and
development of putative knuckle-walking features of the wrist in apes and
monkeys. We use these data to test the hypothesis that all knuckle-walking
apes share similar anatomical features and that these features can be used
to reliably infer locomotor behavior in our extinct ancestors. Contrary to
previous expectations, features long-assumed to indicate knuckle-walking
behavior are not found in all African apes, show different developmental
patterns across species, and are found in nonknuckle-walking primates as
well. However, variation among African ape wrist morphology can be clearly
explained if we accept the likely independent evolution of 2 fundamentally
different biomechanical modes of knuckle-walking: an extended wrist posture
in an arboreal environment (Pan) versus a neutral, columnar hand posture in
a terrestrial environment (Gorilla). The presence of purported
knuckle-walking features in the hominin wrist can thus be viewed as evidence
of arboreality, not terrestriality, and provide evidence that human
bipedalism evolved from a more arboreal ancestor occupying the ecological
niche common to all living apes.
[/quote:ae82763c51]
Geez, Marco, *in the trees*. Who'da thunk it.
And no mention of water anywhere. |
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| RichTravsky... |
| Posted: Wed Aug 26, 2009 11:03 pm |
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Guest
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mclark wrote:
[quote:94ee59f1b6]
On Aug 25, 6:23 pm, Marc Verhaegen <m_verhae... at (no spam) skynet.be> wrote:
Independent evolution of knuckle-walking in African apes shows that humans
did not evolve from a knuckle-walking ancestor
TL Kivell & D Schmitt 2009 PNAS 106:14241-6
Despite decades of debate, it remains unclear whether human bipedalism
evolved from a terrestrial knuckle-walking ancestor or from a more
generalized, arboreal ape ancestor. Proponents of the knuckle-walking
hypothesis focused on the wrist and hand to find morphological evidence of
this behavior in the human fossil record. These studies, however, have not
examined variation or development of purported knuckle-walking features in
apes or other primates, data that are critical to resolution of this
long-standing debate. Here we present novel data on the frequency and
development of putative knuckle-walking features of the wrist in apes and
monkeys. We use these data to test the hypothesis that all knuckle-walking
apes share similar anatomical features and that these features can be used
to reliably infer locomotor behavior in our extinct ancestors. Contrary to
previous expectations, features long-assumed to indicate knuckle-walking
behavior are not found in all African apes, show different developmental
patterns across species, and are found in nonknuckle-walking primates as
well. However, variation among African ape wrist morphology can be clearly
explained if we accept the likely independent evolution of 2 fundamentally
different biomechanical modes of knuckle-walking: an extended wrist posture
in an arboreal environment (Pan) versus a neutral, columnar hand posture in
a terrestrial environment (Gorilla). The presence of purported
knuckle-walking features in the hominin wrist can thus be viewed as evidence
of arboreality, not terrestriality, and provide evidence that human
bipedalism evolved from a more arboreal ancestor occupying the ecological
niche common to all living apes.
Geez, Marco, *in the trees*. Who'da thunk it.
And no mention of water anywhere.
[/quote:94ee59f1b6]
You weren't supposed to notice that part. |
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| RichTravsky... |
| Posted: Wed Aug 26, 2009 11:11 pm |
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Guest
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Marc Verhaegen wrote:
[quote:9fd8b39de4]
Independent evolution of knuckle-walking in African apes shows that humans did not
evolve from a knuckle-walking ancestor
TL Kivell & D Schmitt 2009 PNAS 106:14241-6
[/quote:9fd8b39de4]
Discussed last week, child.
Our data cannot reject the hypothesis that knuckle-walking evolved only once at
the base of the African ape and human clade and that these differences evolved
after the Gorilla and Pan split.
Features found in the hominin fossil record that have traditionally been
associated with a broad definition of knuckle-walking are more likely reflecting
the habitual Pan-like use of extended wrist postures that are particularly
advantageous in an arboreal environment. This, in turn, suggests that human
bipedality evolved from a more arboreal ancestor occupying a generalized
locomotor and ecological niche common to all living apes.
The authors apparently did not consider australopithecines, which were
obligate bipeds with vestigial knuckle walking features. |
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| RichTravsky... |
| Posted: Mon Sep 07, 2009 6:38 pm |
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Guest
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Marc Verhaegen wrote:
[quote:d7194e7455]
[/quote:d7194e7455]
... knuckle-walking is not the same biomechanical phenomenon in Pan and Gorilla.
Previous researchers have noted postural (16, 31, 32) and biomechanical (13, 14)
differences in knuckle-walking behavior among African apes and our hypothesis
expands upon this foundation of work to suggest that knuckle-walking is a
fundamentally different mode of locomotion in Pan and Gorilla.
We propose that Gorilla uses a relative "columnar" forelimb posture during
knuckle-walking in which the hand and wrist joints are aligned in a relatively
straight, neutral posture compared to the more extended postures adopted by
Pan.
The variation in African ape hand posture may be more completely understood
through a consideration of differences in substrate use ... Specifically,
we propose that features traditionally associated with knuckle-walking may
actually reflect the habitual loading of the wrist in an extended posture on
arboreal substrates.
The results of this study show that researchers need to reevaluate all posited
knuckle-walking features and reconsider their efficacy as indicators of
knuckle-walking behavior in extant and extinct primates. In this context, the
absence of several posited knuckle-walking features in extant knuckle-walkers
(and the presence of some of these features in nonknuckle-walkers) makes it
difficult to argue that there is unambiguous evidence that bipedalism evolved
from a terrestrial knuckle-walking ancestor. Instead, our data support the
opposite notion, thatfeatures of the hand and wrist found in the human fossil
record that have traditionally been treated as indicators of knucklewalking
behavior are in fact evidence of arboreality and not terrestriality.
which in and of itself is not new, just better quantified.
Our data cannot reject the hypothesis that knuckle-walking evolved only once at
the base of the African ape and human clade and that these differences evolved
after the Gorilla and Pan split.
Features found in the hominin fossil record that have traditionally been
associated with a broad definition of knuckle-walking are more likely reflecting
the habitual Pan-like use of extended wrist postures that are particularly
advantageous in an arboreal environment. This, in turn, suggests that human
bipedality evolved from a more arboreal ancestor occupying a generalized
locomotor and ecological niche common to all living apes. |
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| deowll... |
| Posted: Mon Oct 05, 2009 11:36 pm |
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Guest
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"RichTravsky" <traRvEsky at (no spam) hotmMOVEail.com> wrote in message
news:4AA5A76B.26396D9B at (no spam) hotmMOVEail.com...
[quote:1a292b380d]Marc Verhaegen wrote:
... knuckle-walking is not the same biomechanical phenomenon in Pan and
Gorilla.
Previous researchers have noted postural (16, 31, 32) and biomechanical
(13, 14)
differences in knuckle-walking behavior among African apes and our
hypothesis
expands upon this foundation of work to suggest that knuckle-walking is a
fundamentally different mode of locomotion in Pan and Gorilla.
We propose that Gorilla uses a relative "columnar" forelimb posture during
knuckle-walking in which the hand and wrist joints are aligned in a
relatively
straight, neutral posture compared to the more extended postures adopted
by
Pan.
The variation in African ape hand posture may be more completely
understood
through a consideration of differences in substrate use ... Specifically,
we propose that features traditionally associated with knuckle-walking may
actually reflect the habitual loading of the wrist in an extended posture
on
arboreal substrates.
The results of this study show that researchers need to reevaluate all
posited
knuckle-walking features and reconsider their efficacy as indicators of
knuckle-walking behavior in extant and extinct primates. In this context,
the
absence of several posited knuckle-walking features in extant
knuckle-walkers
(and the presence of some of these features in nonknuckle-walkers) makes
it
difficult to argue that there is unambiguous evidence that bipedalism
evolved
from a terrestrial knuckle-walking ancestor. Instead, our data support the
opposite notion, thatfeatures of the hand and wrist found in the human
fossil
record that have traditionally been treated as indicators of
knucklewalking
behavior are in fact evidence of arboreality and not terrestriality.
which in and of itself is not new, just better quantified.
Our data cannot reject the hypothesis that knuckle-walking evolved only
once at
the base of the African ape and human clade and that these differences
evolved
after the Gorilla and Pan split.
Features found in the hominin fossil record that have traditionally been
associated with a broad definition of knuckle-walking are more likely
reflecting
the habitual Pan-like use of extended wrist postures that are particularly
advantageous in an arboreal environment. This, in turn, suggests that
human
bipedality evolved from a more arboreal ancestor occupying a generalized
locomotor and ecological niche common to all living apes.
[/quote:1a292b380d]
I suppose the role the obvious weight difference between Gorilla and Pan
might have played in locomotion adoptions was to obscure for them to
consider? The oversight does not commend them to me. |
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| RichTravsky... |
| Posted: Sun Oct 11, 2009 11:18 pm |
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Guest
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deowll wrote:
[quote:60e32c6339]"RichTravsky" <traRvEsky at (no spam) hotmMOVEail.com> wrote in message
Marc Verhaegen wrote:
... knuckle-walking is not the same biomechanical phenomenon in Pan and
Gorilla.
Previous researchers have noted postural (16, 31, 32) and biomechanical
(13, 14)
differences in knuckle-walking behavior among African apes and our
hypothesis
expands upon this foundation of work to suggest that knuckle-walking is a
fundamentally different mode of locomotion in Pan and Gorilla.
We propose that Gorilla uses a relative "columnar" forelimb posture during
knuckle-walking in which the hand and wrist joints are aligned in a
relatively
straight, neutral posture compared to the more extended postures adopted
by
Pan.
The variation in African ape hand posture may be more completely
understood
through a consideration of differences in substrate use ... Specifically,
we propose that features traditionally associated with knuckle-walking may
actually reflect the habitual loading of the wrist in an extended posture
on
arboreal substrates.
The results of this study show that researchers need to reevaluate all
posited
knuckle-walking features and reconsider their efficacy as indicators of
knuckle-walking behavior in extant and extinct primates. In this context,
the
absence of several posited knuckle-walking features in extant
knuckle-walkers
(and the presence of some of these features in nonknuckle-walkers) makes
it
difficult to argue that there is unambiguous evidence that bipedalism
evolved
from a terrestrial knuckle-walking ancestor. Instead, our data support the
opposite notion, thatfeatures of the hand and wrist found in the human
fossil
record that have traditionally been treated as indicators of
knucklewalking
behavior are in fact evidence of arboreality and not terrestriality.
which in and of itself is not new, just better quantified.
Our data cannot reject the hypothesis that knuckle-walking evolved only
once at
the base of the African ape and human clade and that these differences
evolved
after the Gorilla and Pan split.
Features found in the hominin fossil record that have traditionally been
associated with a broad definition of knuckle-walking are more likely
reflecting
the habitual Pan-like use of extended wrist postures that are particularly
advantageous in an arboreal environment. This, in turn, suggests that
human
bipedality evolved from a more arboreal ancestor occupying a generalized
locomotor and ecological niche common to all living apes.
I suppose the role the obvious weight difference between Gorilla and Pan
might have played in locomotion adoptions was to obscure for them to
consider? The oversight does not commend them to me.
[/quote:60e32c6339]
The weight difference is not as pertinent as the fact that they adopted the
essentially same modes of locomotion. |
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| deowll... |
| Posted: Sun Oct 11, 2009 11:38 pm |
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Guest
|
"RichTravsky" <traRvEsky at (no spam) hotmMOVEail.com> wrote in message
news:4AD2BC36.3550A648 at (no spam) hotmMOVEail.com...
[quote:b9df23aad6]deowll wrote:
"RichTravsky" <traRvEsky at (no spam) hotmMOVEail.com> wrote in message
Marc Verhaegen wrote:
... knuckle-walking is not the same biomechanical phenomenon in Pan and
Gorilla.
Previous researchers have noted postural (16, 31, 32) and biomechanical
(13, 14)
differences in knuckle-walking behavior among African apes and our
hypothesis
expands upon this foundation of work to suggest that knuckle-walking is
a
fundamentally different mode of locomotion in Pan and Gorilla.
We propose that Gorilla uses a relative "columnar" forelimb posture
during
knuckle-walking in which the hand and wrist joints are aligned in a
relatively
straight, neutral posture compared to the more extended postures
adopted
by
Pan.
The variation in African ape hand posture may be more completely
understood
through a consideration of differences in substrate use ...
Specifically,
we propose that features traditionally associated with knuckle-walking
may
actually reflect the habitual loading of the wrist in an extended
posture
on
arboreal substrates.
The results of this study show that researchers need to reevaluate all
posited
knuckle-walking features and reconsider their efficacy as indicators of
knuckle-walking behavior in extant and extinct primates. In this
context,
the
absence of several posited knuckle-walking features in extant
knuckle-walkers
(and the presence of some of these features in nonknuckle-walkers)
makes
it
difficult to argue that there is unambiguous evidence that bipedalism
evolved
from a terrestrial knuckle-walking ancestor. Instead, our data support
the
opposite notion, thatfeatures of the hand and wrist found in the human
fossil
record that have traditionally been treated as indicators of
knucklewalking
behavior are in fact evidence of arboreality and not terrestriality.
which in and of itself is not new, just better quantified.
Our data cannot reject the hypothesis that knuckle-walking evolved only
once at
the base of the African ape and human clade and that these differences
evolved
after the Gorilla and Pan split.
Features found in the hominin fossil record that have traditionally
been
associated with a broad definition of knuckle-walking are more likely
reflecting
the habitual Pan-like use of extended wrist postures that are
particularly
advantageous in an arboreal environment. This, in turn, suggests that
human
bipedality evolved from a more arboreal ancestor occupying a
generalized
locomotor and ecological niche common to all living apes.
I suppose the role the obvious weight difference between Gorilla and Pan
might have played in locomotion adoptions was to obscure for them to
consider? The oversight does not commend them to me.
The weight difference is not as pertinent as the fact that they adopted
the
essentially same modes of locomotion.
[/quote:b9df23aad6]
But as you note there are differences which has to mean something. |
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| RichTravsky... |
| Posted: Sun Oct 25, 2009 11:24 pm |
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Guest
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deowll wrote:
[quote]"RichTravsky" <traRvEsky at (no spam) hotmMOVEail.com> wrote in message
deowll wrote:
"RichTravsky" <traRvEsky at (no spam) hotmMOVEail.com> wrote in message
Marc Verhaegen wrote:
... knuckle-walking is not the same biomechanical phenomenon in Pan and
Gorilla.
Previous researchers have noted postural (16, 31, 32) and biomechanical
(13, 14)
differences in knuckle-walking behavior among African apes and our
hypothesis
expands upon this foundation of work to suggest that knuckle-walking is
a
fundamentally different mode of locomotion in Pan and Gorilla.
We propose that Gorilla uses a relative "columnar" forelimb posture
during
knuckle-walking in which the hand and wrist joints are aligned in a
relatively
straight, neutral posture compared to the more extended postures
adopted
by
Pan.
The variation in African ape hand posture may be more completely
understood
through a consideration of differences in substrate use ...
Specifically,
we propose that features traditionally associated with knuckle-walking
may
actually reflect the habitual loading of the wrist in an extended
posture
on
arboreal substrates.
The results of this study show that researchers need to reevaluate all
posited
knuckle-walking features and reconsider their efficacy as indicators of
knuckle-walking behavior in extant and extinct primates. In this
context,
the
absence of several posited knuckle-walking features in extant
knuckle-walkers
(and the presence of some of these features in nonknuckle-walkers)
makes
it
difficult to argue that there is unambiguous evidence that bipedalism
evolved
from a terrestrial knuckle-walking ancestor. Instead, our data support
the
opposite notion, thatfeatures of the hand and wrist found in the human
fossil
record that have traditionally been treated as indicators of
knucklewalking
behavior are in fact evidence of arboreality and not terrestriality.
which in and of itself is not new, just better quantified.
Our data cannot reject the hypothesis that knuckle-walking evolved only
once at
the base of the African ape and human clade and that these differences
evolved
after the Gorilla and Pan split.
Features found in the hominin fossil record that have traditionally
been
associated with a broad definition of knuckle-walking are more likely
reflecting
the habitual Pan-like use of extended wrist postures that are
particularly
advantageous in an arboreal environment. This, in turn, suggests that
human
bipedality evolved from a more arboreal ancestor occupying a
generalized
locomotor and ecological niche common to all living apes.
I suppose the role the obvious weight difference between Gorilla and Pan
might have played in locomotion adoptions was to obscure for them to
consider? The oversight does not commend them to me.
The weight difference is not as pertinent as the fact that they adopted
the
essentially same modes of locomotion.
But as you note there are differences which has to mean something.
[/quote]
No, one is larger and heavier, and the mode of locomotion may have a minimum weight
at which this mode becomes advantageous. |
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| deowll... |
| Posted: Thu Oct 29, 2009 11:16 pm |
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Guest
|
"RichTravsky" <traRvEsky at (no spam) hotmMOVEail.com> wrote in message
news:4AE5329B.4C65E989 at (no spam) hotmMOVEail.com...
[quote]deowll wrote:
"RichTravsky" <traRvEsky at (no spam) hotmMOVEail.com> wrote in message
deowll wrote:
"RichTravsky" <traRvEsky at (no spam) hotmMOVEail.com> wrote in message
Marc Verhaegen wrote:
... knuckle-walking is not the same biomechanical phenomenon in Pan
and
Gorilla.
Previous researchers have noted postural (16, 31, 32) and
biomechanical
(13, 14)
differences in knuckle-walking behavior among African apes and our
hypothesis
expands upon this foundation of work to suggest that knuckle-walking
is
a
fundamentally different mode of locomotion in Pan and Gorilla.
We propose that Gorilla uses a relative "columnar" forelimb posture
during
knuckle-walking in which the hand and wrist joints are aligned in a
relatively
straight, neutral posture compared to the more extended postures
adopted
by
Pan.
The variation in African ape hand posture may be more completely
understood
through a consideration of differences in substrate use ...
Specifically,
we propose that features traditionally associated with
knuckle-walking
may
actually reflect the habitual loading of the wrist in an extended
posture
on
arboreal substrates.
The results of this study show that researchers need to reevaluate
all
posited
knuckle-walking features and reconsider their efficacy as indicators
of
knuckle-walking behavior in extant and extinct primates. In this
context,
the
absence of several posited knuckle-walking features in extant
knuckle-walkers
(and the presence of some of these features in nonknuckle-walkers)
makes
it
difficult to argue that there is unambiguous evidence that
bipedalism
evolved
from a terrestrial knuckle-walking ancestor. Instead, our data
support
the
opposite notion, thatfeatures of the hand and wrist found in the
human
fossil
record that have traditionally been treated as indicators of
knucklewalking
behavior are in fact evidence of arboreality and not terrestriality.
which in and of itself is not new, just better quantified.
Our data cannot reject the hypothesis that knuckle-walking evolved
only
once at
the base of the African ape and human clade and that these
differences
evolved
after the Gorilla and Pan split.
Features found in the hominin fossil record that have traditionally
been
associated with a broad definition of knuckle-walking are more
likely
reflecting
the habitual Pan-like use of extended wrist postures that are
particularly
advantageous in an arboreal environment. This, in turn, suggests
that
human
bipedality evolved from a more arboreal ancestor occupying a
generalized
locomotor and ecological niche common to all living apes.
I suppose the role the obvious weight difference between Gorilla and
Pan
might have played in locomotion adoptions was to obscure for them to
consider? The oversight does not commend them to me.
The weight difference is not as pertinent as the fact that they adopted
the
essentially same modes of locomotion.
But as you note there are differences which has to mean something.
No, one is larger and heavier, and the mode of locomotion may have a
minimum weight
at which this mode becomes advantageous.
[/quote]
Okay so you don't understand what happens when you seriously scale an animal
up.
Your problem. |
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| RichTravsky... |
| Posted: Sun Nov 01, 2009 9:45 pm |
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Guest
|
deowll wrote:
[quote]"RichTravsky" <traRvEsky at (no spam) hotmMOVEail.com> wrote in message
deowll wrote:
"RichTravsky" <traRvEsky at (no spam) hotmMOVEail.com> wrote in message
deowll wrote:
"RichTravsky" <traRvEsky at (no spam) hotmMOVEail.com> wrote in message
Marc Verhaegen wrote:
... knuckle-walking is not the same biomechanical phenomenon in Pan
and
Gorilla.
Previous researchers have noted postural (16, 31, 32) and
biomechanical
(13, 14)
differences in knuckle-walking behavior among African apes and our
hypothesis
expands upon this foundation of work to suggest that knuckle-walking
is
a
fundamentally different mode of locomotion in Pan and Gorilla.
We propose that Gorilla uses a relative "columnar" forelimb posture
during
knuckle-walking in which the hand and wrist joints are aligned in a
relatively
straight, neutral posture compared to the more extended postures
adopted
by
Pan.
The variation in African ape hand posture may be more completely
understood
through a consideration of differences in substrate use ...
Specifically,
we propose that features traditionally associated with
knuckle-walking
may
actually reflect the habitual loading of the wrist in an extended
posture
on
arboreal substrates.
The results of this study show that researchers need to reevaluate
all
posited
knuckle-walking features and reconsider their efficacy as indicators
of
knuckle-walking behavior in extant and extinct primates. In this
context,
the
absence of several posited knuckle-walking features in extant
knuckle-walkers
(and the presence of some of these features in nonknuckle-walkers)
makes
it
difficult to argue that there is unambiguous evidence that
bipedalism
evolved
from a terrestrial knuckle-walking ancestor. Instead, our data
support
the
opposite notion, thatfeatures of the hand and wrist found in the
human
fossil
record that have traditionally been treated as indicators of
knucklewalking
behavior are in fact evidence of arboreality and not terrestriality.
which in and of itself is not new, just better quantified.
Our data cannot reject the hypothesis that knuckle-walking evolved
only
once at
the base of the African ape and human clade and that these
differences
evolved
after the Gorilla and Pan split.
Features found in the hominin fossil record that have traditionally
been
associated with a broad definition of knuckle-walking are more
likely
reflecting
the habitual Pan-like use of extended wrist postures that are
particularly
advantageous in an arboreal environment. This, in turn, suggests
that
human
bipedality evolved from a more arboreal ancestor occupying a
generalized
locomotor and ecological niche common to all living apes.
I suppose the role the obvious weight difference between Gorilla and
Pan
might have played in locomotion adoptions was to obscure for them to
consider? The oversight does not commend them to me.
The weight difference is not as pertinent as the fact that they adopted
the
essentially same modes of locomotion.
But as you note there are differences which has to mean something.
No, one is larger and heavier, and the mode of locomotion may have a
minimum weight
at which this mode becomes advantageous.
Okay so you don't understand what happens when you seriously scale an animal
up.
Your problem.
[/quote]
Orangs do not knuckle walk. But that's because they don't spend as much time on
the ground.
Average weights (loosely) (males)
http://www.apetag.org/aboutApes.html
Orang 175-200 pounds
chimp 90-132 "
gorilla 350-400 " |
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The time now is Sun Nov 22, 2009 3:50 am
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