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| Lee Olsen... |
 Posted: Thu Oct 01, 2009 6:56 am |
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| Andrew Nowicki... |
| Posted: Thu Oct 01, 2009 6:11 pm |
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Ardi (Ardipithecus Ramidus) was a bipedal omnivore living in a
woodland. Bipedal posture is not useful for picking food from the
ground, but it is perfect posture for wading because wading reduces
heat loss to water and hydrodynamic drag and because you can see the
aquatic environment well from the high vantage point of your bipedal
body. There was plenty of food in aquatic roots, bulbs, tubers,
rhizomes, corms, sprouts and stems. The best way to exploit this food
source was pulling the food out with dexterous hands, strong spine,
and very strong buttock muscles (gluteus maximus). Unlike apes, we
have very large buttock muscles. They are needed for stooping rather
than walking, running, or jumping. |
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| Lee Olsen... |
| Posted: Thu Oct 01, 2009 6:58 pm |
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On Oct 1, 9:11 pm, Andrew Nowicki <andrew.nowicki... at (no spam) gmail.com> wrote:
[quote:4dd7d92b84]Ardi (Ardipithecus Ramidus) was a bipedal omnivore living in a
woodland. Bipedal posture is not useful for picking food from the
ground,
[/quote:4dd7d92b84]
I'm going to bet Ardi had longer arms than later Homo, who had no
trouble picking stones off the ground and bashing bones to pieces
on the ground. |
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| Marc Verhaegen... |
| Posted: Fri Oct 02, 2009 12:53 am |
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Op 02-10-2009 06:11, in artikel
f16e2621-2106-45e5-8c54-5f09c03651b5 at (no spam) c37g2000yqi.googlegroups.com, Andrew
Nowicki <andrew.nowicki.00 at (no spam) gmail.com> schreef:
[quote:3848c719be]Ardi (Ardipithecus Ramidus) was a bipedal omnivore living in a
woodland. Bipedal posture is not useful for picking food from the
ground, but it is perfect posture for wading because wading reduces
heat loss to water and hydrodynamic drag and because you can see the
aquatic environment well from the high vantage point of your bipedal
body. There was plenty of food in aquatic roots, bulbs, tubers,
rhizomes, corms, sprouts and stems. The best way to exploit this food
source was pulling the food out with dexterous hands, strong spine,
and very strong buttock muscles (gluteus maximus). Unlike apes, we
have very large buttock muscles. They are needed for stooping rather
than walking, running, or jumping.
[/quote:3848c719be]
Yes, Andrew, Ardip seems to have been a wader-climber in densely vegetated
swamp forests full of herons & other waterbirds (google aquarboreal). It was
a fossil African ape, but not necessarily closely related to one of the
living hominids (gorillas, humans, chimps). I see no reason to think it was
a human ancestor. But let's first read the papers in Science in detail.
--marc |
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| rmacfarl... |
| Posted: Fri Oct 02, 2009 1:22 am |
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| mclark... |
| Posted: Fri Oct 02, 2009 3:23 am |
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On Oct 2, 2:22 am, "rmacfarl" <rmacf... at (no spam) alphalink.com.au> wrote:
[quote:f15ceb47c9]"Lee Olsen" <paleoc... at (no spam) hotmail.com> wrote in messagenews:3cf6bc3c-d088-4b89-b1ca-40b63efb6530 at (no spam) 12g2000pri.googlegroups.com...
http://tinyurl.com/y9kghr6
PA goes viral:
http://blogs.discovermagazine.com/loom/2009/10/01/ardipithecus-we-mee...http://www.msnbc.msn.com/id/33110809/ns/technology_and_science-scienc...http://www.dailymail.co.uk/sciencetech/article-1217400/Ardi-skeleton-...http://johnhawks.net/weblog/fossils/ardipithecus/ardipithecus-faq-200...http://michael-balter.blogspot.com/2009/10/ardi.htmlhttp://tinyurl.com/ydbnbar(downloadable mp3 of NewsHour interview)
or visithttp://www.pbs.org/newshour/newshour_index.htmland watch on line (from October 1 lineup)
Interesting that it's interpreted as an arboreal quadruped and a terrestrial biped. MClark, your thoughts?
[/quote:f15ceb47c9]
Ho hum. That's right up Crompton's alley. isn't it? It looks to me
like
a puzzle piece that fits perfectly. I see Marco is claiming that they
lived in "gallery forests" and waded alot. I swear, you can set your
watch by him.
From Hawk's page:
" The last common ancestor of hominids and chimpanzees was
therefore a careful climber that retained adaptations to above-branch
plantigrady."
and
"After sampling carbon and oxygen stable isotopes in five
Ardipithecus individuals, they conclude that it had a C4
plant consumption much less than later australopithecines,
while higher than the very minimal value in chimpanzees,
and that it habitually lived in mesic
(not too wet, not too dry) habitat."
and (from Lovejoy)
"It also reveals an unanticipated and distinct locomotor
bauplan for our last common ancestors with African apes,
one based on careful climbing unpreserved in any extant form...."
Looks like today, Oct 2, 2009, (publication of the papers)
is a big day in Paleo Anthropology. I wonder if the peanut
gallery is paying any attention....(?)
[quote:f15ceb47c9]"A study of Ardi, under way since the first bones were discovered in 1994, indicates the species lived in the woodlands and could climb on all fours along tree branches, but the development of their arms and legs indicates they didn't spend much time in the trees. And they could walk upright, on two legs, when on the ground."
[Quoted from the msnbc link above.]
Ross Macfarlane[/quote:f15ceb47c9] |
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| Lee Olsen... |
| Posted: Fri Oct 02, 2009 3:29 am |
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On Oct 1, 11:53 pm, Marc Verhaegen <m_verhae... at (no spam) skynet.be> wrote:
[quote:ed42a1e5ae]Op 02-10-2009 06:11, in artikel
f16e2621-2106-45e5-8c54-5f09c0365... at (no spam) c37g2000yqi.googlegroups.com, Andrew
Nowicki <andrew.nowicki... at (no spam) gmail.com> schreef:
Ardi (Ardipithecus Ramidus) was a bipedal omnivore living in a
woodland. Bipedal posture is not useful for picking food from the
ground, but it is perfect posture for wading because wading reduces
heat loss to water and hydrodynamic drag and because you can see the
aquatic environment well from the high vantage point of your bipedal
body. There was plenty of food in aquatic roots, bulbs, tubers,
rhizomes, corms, sprouts and stems. The best way to exploit this food
source was pulling the food out with dexterous hands, strong spine,
and very strong buttock muscles (gluteus maximus). Unlike apes, we
have very large buttock muscles. They are needed for stooping rather
than walking, running, or jumping.
Yes, Andrew, Ardip seems to have been a wader-climber in densely vegetated
swamp forests full of herons & other waterbirds (google aquarboreal).
[/quote:ed42a1e5ae]
So, in orangs, who also live in in densely vegetated swamp forests,
were
also aquarborealists too? |
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| Lee Olsen... |
| Posted: Fri Oct 02, 2009 4:26 am |
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On Oct 2, 6:23 am, mclark <mbclar... at (no spam) comcast.net> wrote:
[quote:68df3a7f6f]
"After sampling carbon and oxygen stable isotopes in five
Ardipithecus individuals, they conclude that it had a C4
plant consumption much less than later australopithecines,
while higher than the very minimal value in chimpanzees,
and that it habitually lived in mesic
(not too wet, not too dry) habitat."
[/quote:68df3a7f6f]
If Ardi really lived in a "densely vegetated swamp" forest, as
Marc claims, then why would the fossils of it be found at all?
Forests make for poor preservation, as the dearth of chimp
bones demonstrate. The only fossil chimp teeth are relatively
late, found in the rift, and probably some sort of dry/savanna
attempt like these chimps are doing:
http://www.sciencedaily.com/releases/2007/11/071112172155.htm |
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| rmacfarl... |
| Posted: Sat Oct 03, 2009 1:41 am |
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On Oct 2, 6:23 am, mclark <mbclar... at (no spam) comcast.net> wrote:
[quote:c817d8e4e8]
"After sampling carbon and oxygen stable isotopes in five
Ardipithecus individuals, they conclude that it had a C4
plant consumption much less than later australopithecines,
while higher than the very minimal value in chimpanzees,
and that it habitually lived in mesic
(not too wet, not too dry) habitat."
[/quote:c817d8e4e8]
The finding of arboreal quadruped and a terrestrial biped doesn't
seem consistent with a hypothesis that bipedality evolved in the
trees, would you agree Mike? |
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| mclark... |
| Posted: Sat Oct 03, 2009 4:07 am |
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On Oct 3, 2:41 am, "rmacfarl" <rmacf... at (no spam) alphalink.com.au> wrote:
[quote:0d35d758d1]On Oct 2, 6:23 am, mclark <mbclar... at (no spam) comcast.net> wrote:
"After sampling carbon and oxygen stable isotopes in five
Ardipithecus individuals, they conclude that it had a C4
plant consumption much less than later australopithecines,
while higher than the very minimal value in chimpanzees,
and that it habitually lived in mesic
(not too wet, not too dry) habitat."
The finding of arboreal quadruped and a terrestrial biped doesn't
seem consistent with a hypothesis that bipedality evolved in the
trees, would you agree Mike?
[/quote:0d35d758d1]
Yea, that would be my first thought. On second thought,
I'm not so sure I'm going to sign on to the "arboreal
quadruped" thing. Clearly bipedal on the ground,
clearly a "slow climber", clearly "transitional", I
don't see any ~other~ substrate on the horizon nor
any other selective choreography which would
produce such a desirable end. I would add here
that I'm a bit skeptical of Lovejoy's reduced canine
<-> altered social structure but it makes large sense
and adds a new dimension to this whole discussion.
Let's see what other discussion we can find today.
I see somebody left Crowley's cage door open
again. See below. |
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| RichTravsky... |
| Posted: Sun Oct 04, 2009 10:22 pm |
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Andrew Nowicki wrote:
[quote:a637294a59]
Ardi (Ardipithecus Ramidus) was a bipedal omnivore living in a
woodland. Bipedal posture is not useful for picking food from the
[/quote:a637294a59]
It's very useful for spotting food - "high vantage point". Bending over is a
trivial matter. We humans do it ALL the time.
[quote:a637294a59]ground, but it is perfect posture for wading because wading reduces
heat loss to water and hydrodynamic drag and because you can see the
[/quote:a637294a59]
Drag? from wading? Must be mighty fast wading...
[quote:a637294a59]aquatic environment well from the high vantage point of your bipedal
body. There was plenty of food in aquatic roots, bulbs, tubers,
rhizomes, corms, sprouts and stems. The best way to exploit this food
[/quote:a637294a59]
More food on land.
[quote:a637294a59]source was pulling the food out with dexterous hands, strong spine,
and very strong buttock muscles (gluteus maximus). Unlike apes, we
have very large buttock muscles. They are needed for stooping rather
than walking, running, or jumping.
[/quote:a637294a59]
Stooping? You make no sense - just above you count that as a negative. Make
up your mind. Our gluts are for bipedal locomotion - like running and
jumping. |
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| RichTravsky... |
| Posted: Sun Oct 04, 2009 10:26 pm |
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Marc Verhaegen wrote:
[quote:151f1884cd]
Op 02-10-2009 06:11, in artikel
f16e2621-2106-45e5-8c54-5f09c03651b5 at (no spam) c37g2000yqi.googlegroups.com, Andrew
Nowicki <andrew.nowicki.00 at (no spam) gmail.com> schreef:
Ardi (Ardipithecus Ramidus) was a bipedal omnivore living in a
woodland. Bipedal posture is not useful for picking food from the
ground, but it is perfect posture for wading because wading reduces
heat loss to water and hydrodynamic drag and because you can see the
aquatic environment well from the high vantage point of your bipedal
body. There was plenty of food in aquatic roots, bulbs, tubers,
rhizomes, corms, sprouts and stems. The best way to exploit this food
source was pulling the food out with dexterous hands, strong spine,
and very strong buttock muscles (gluteus maximus). Unlike apes, we
have very large buttock muscles. They are needed for stooping rather
than walking, running, or jumping.
Yes, Andrew, Ardip seems to have been a wader-climber in densely vegetated
swamp forests full of herons & other waterbirds (google aquarboreal). It was
[/quote:151f1884cd]
Wrong. No swamp forest.
The combination of geological and taphonomic evidence, the
assemblage of small-mammal and avian fossils, and the taxonomic
and isotopic compositions of remains from larger mammals indicate
that Aramis was predominantly a woodland habitat during Ar.
ramidus times. The anatomical and isotopic evidence of Ar. ramidus
itself also suggests that the species was adapted to such a habitat. |
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| RichTravsky... |
| Posted: Sun Oct 04, 2009 10:26 pm |
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Lee Olsen wrote:
[quote:fa49072638]On Oct 1, 11:53 pm, Marc Verhaegen <m_verhae... at (no spam) skynet.be> wrote:
Op 02-10-2009 06:11, in artikel
f16e2621-2106-45e5-8c54-5f09c0365... at (no spam) c37g2000yqi.googlegroups.com, Andrew
Nowicki <andrew.nowicki... at (no spam) gmail.com> schreef:
Ardi (Ardipithecus Ramidus) was a bipedal omnivore living in a
woodland. Bipedal posture is not useful for picking food from the
ground, but it is perfect posture for wading because wading reduces
heat loss to water and hydrodynamic drag and because you can see the
aquatic environment well from the high vantage point of your bipedal
body. There was plenty of food in aquatic roots, bulbs, tubers,
rhizomes, corms, sprouts and stems. The best way to exploit this food
source was pulling the food out with dexterous hands, strong spine,
and very strong buttock muscles (gluteus maximus). Unlike apes, we
have very large buttock muscles. They are needed for stooping rather
than walking, running, or jumping.
Yes, Andrew, Ardip seems to have been a wader-climber in densely vegetated
swamp forests full of herons & other waterbirds (google aquarboreal).
So, in orangs, who also live in in densely vegetated swamp forests,
were
also aquarborealists too?
[/quote:fa49072638]
No answer. |
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| RichTravsky... |
| Posted: Sun Oct 04, 2009 10:32 pm |
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Marc Verhaegen wrote:
[quote:4b51a2674a]
Ardi (Ardipithecus Ramidus) was a bipedal omnivore living in a
woodland. Bipedal posture is not useful for picking food from the
ground, but it is perfect posture for wading because wading reduces
heat loss to water and hydrodynamic drag and because you can see the
aquatic environment well from the high vantage point of your bipedal
body. There was plenty of food in aquatic roots, bulbs, tubers,
rhizomes, corms, sprouts and stems. The best way to exploit this food
source was pulling the food out with dexterous hands, strong spine,
and very strong buttock muscles (gluteus maximus). Unlike apes, we
have very large buttock muscles. They are needed for stooping rather
than walking, running, or jumping.
Yes, Andrew, Ardip seems to have been a wader-climber in densely vegetated
swamp forests full of herons & other waterbirds (google aquarboreal). It was
a fossil African ape, but not necessarily closely related to one of the
living hominids (gorillas, humans, chimps). I see no reason to think it was
a human ancestor. But let's first read the papers in Science in detail.
The Science papers can be uploaded for free after free registration at
http://www.sciencemag.org/ardipithecus/
Not so densely vegetated apparently:
[/quote:4b51a2674a]
predominantly a woodland habitat
[quote:4b51a2674a]assemblages. The combined results suggest that Ar.ramidus occupied a wooded
Pliocene habitat.
[/quote:4b51a2674a]
wooded |
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| RichTravsky... |
| Posted: Sun Oct 04, 2009 10:43 pm |
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Paul Crowley wrote:
[quote:1d85038c8e]
mclark wrote:
The combined
results suggest that Ar.ramidus occupied a wooded
Pliocene habitat.
Gerrit
We have a great piece of scientific investigation,
but what does Mikey find in all of it?
Look at this:
"Breakthrough adaptations can transform life-history by
deviating from typical reproductive strategy. Early hominids
show feminized male canines (left) and primitive bipedality
(right). These suggest that females preferred nonaggressive
males who gained reproductive success by obtaining
copulation in exchange for valuable foods (vested
provisioning). Success would depend on copulatory frequency
with mates whose fertility remained cryptic (e.g., absence
of cycling in mammary size). The result would be reduced
agonism in unrelated females, and cooperative expansion of
day ranges among equally cooperative males, eventually
leading to exploitation of new habitats. "
No matter how good the science, Mikey unerringly
locates the nonsense -- here some flower-power
fantasies based on interpretations that have only
one 'virtue' -- they are politically correct.
[/quote:1d85038c8e]
Ramidus exhibits reduced/feminized canines in males. That is the
data. No political correctness involved.
In basal dimensions, the canines of Ar. ramidus are roughly as
large as those of female chimpanzees and male bonobos, but their
crown heights are shorter (see figure). The Ar. ramidus sample is now
large enough to assure us that males are represented. This means that
male and female canines were not only similar in size, but that the
male canine had been dramatically “feminized” in shape. The crown
of the upper canine in Ar. ramidus was altered from the pointed shape
seen in apes to a less-threatening diamond shape in both males and
females. There is no evidence of honing. The lower canines of Ar.
ramidus are less modified from the inferred female ape condition
than the uppers. The hominid canines from about 6 Ma are similar in
size to those of Ar. ramidus, but (especially) the older upper canines
appear slightly more primitive. This suggests that male canine size
and prominence were dramatically reduced by ~6 to 4.4 Ma from an
ancestral ape with a honing C/P3 complex and a moderate degree of
male and female canine size difference.
In modern monkeys and apes, the upper canine is important in
male agonistic behavior, so its subdued shape in early hominids and
Ar. ramidus suggests that sexual selection played a primary role in
canine reduction. Thus, fundamental reproductive and social behavioral
changes probably occurred in hominids long before they had
enlarged brains and began to use stone tools. |
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