"...To walk upright is to be human. At
least that's what paleoanthropologists
have thought for decades. But now,
researchers have observed orangutans
walking in a way that resembles human
locomotion--albeit along the branches
of trees. This suggests that the earliest
stages of upright walking evolved in apes
living in the trees rather than in
hominids walking on the ground, according
to primatologist Robin Crompton of the
University of Liverpool, U.K., co-author
of the report in tomorrow's
issue of Science..."
http://tinyurl.com/2cl2m7

"...To walk upright is to be human.

"...To walk upright is to be human. At
least that's what paleoanthropologists
have thought for decades. But now,
researchers have observed orangutans
walking in a way that resembles human
locomotion--albeit along the branches
of trees. This suggests that the earliest
stages of upright walking evolved in apes
living in the trees rather than in
hominids walking on the ground, according
to primatologist Robin Crompton of the
University of Liverpool, U.K., co-author
of the report in tomorrow's
issue of Science..."
http://tinyurl.com/2cl2m7

Thanks a lot, m3d.

SKS Thorpe, RL Holder & RH Crompton 2007
"Origin of human bipedalism as an adaptation for locomotion on flexible
branches"
Science 316:1328-31

Human bipedalism is commonly thought to have evolved from a quadrupedal
terrestrial precursor, yet some recent paleontological evidence suggests
that adaptations for bipedalism arose in an arboreal context. However, the
adaptive benefit of arboreal bipedalism has been unknown. Here we show that
it allows the most arboreal great ape, the orangutan, to access supports too
flexible to be negotiated otherwise. Orangutans react to branch flexibility
like humans running on springy tracks, by increasing knee and hip extension,
whereas all other primates do the reverse. Human bipedalism is thus less an
innovation than an exploitation of a locomotor behavior retained from the
common great ape ancestor.
____

Gibbons walk bipedally over branches, orangs do this sometime it now
appears, so perhaps the early apes already did this, but all this does not
explain why no monkeys do this. In any case, it seems to suggest that the
early hominoids were already (parttime) bipedal: wading? branch-hanging?
(from which walking bipedally over branches as in gibbons & orangs & other
apes could have evolved).

Orangs don't knuckle-walk: on the ground (seldom), they walk on the "heels"
of the hand: they fist-walk (with the fingers +-flexed, usu.on the lateral
side of the hand) or palm-walk (with the fingers +-extended).
KWing (Pan & Gorilla) is very derived, in fact more derived than
(short-legged) bipedality as seen in all hominoids now & then. KWing (on
the dorsal side of the hand) can't evolve directly from palmigrady (on the
ventral side of the hand), so there must have been an intermediary phase:
short-legged bipedality in early hominoids, eg, for wading in swamp forests,
where the fossil apes are found. Arm-hanging (alone) does not explain KWing,
since gibbons & orangs & human infants palm-walk.

--Marc Verhaegen
http://allserv.rug.ac.be/~mvaneech/outthere.htm
http://allserv.rug.ac.be/~mvaneech/Symposium.html
http://groups.yahoo.com/group/AAT

On Jun 1, 11:32 am, Marc Verhaegen <m_verhae...@skynet.be> wrote:

"...To walk upright is to be human.

ROFL, let's see an orang make a hand axe, or get 50 flakes from a
single core.

Op 02-06-2007 01:30, in artikel
1180740608.965388.311...@g4g2000hsf.googlegroups.com, Lee Olsen
paleoc...@hotmail.com> schreef:

On Jun 1, 11:32 am, Marc Verhaegen <m_verhae...@skynet.be> wrote:
"...To walk upright is to be human.

Who said that nonsense? Ever heard of penguins?

ROFL, let's see an orang make a hand axe, or get 50 flakes from a
single core.

??
What on earth has walking upright to do with using tools IYO??

Most bipeds = dinos, birds,

Most tool-using animals can't be called bipedal: capuchins, chimps,
sea-otters.
Of the animals that walk upright (penguins... others?), only Hs uses tools
AFAIK.

Got it?

(no!)

"...To walk upright is to be human. At
least that's what paleoanthropologists
have thought for decades. But now,
researchers have observed orangutans
walking in a way that resembles human
locomotion--albeit along the branches
of trees. This suggests that the earliest
stages of upright walking evolved in apes
living in the trees rather than in
hominids walking on the ground, according
to primatologist Robin Crompton of the
University of Liverpool, U.K., co-author
of the report in tomorrow's
issue of Science..."
http://tinyurl.com/2cl2m7

Thanks a lot, m3d.

SKS Thorpe, RL Holder & RH Crompton 2007
"Origin of human bipedalism as an adaptation for locomotion on flexible
branches"
Science 316:1328-31

Human bipedalism is commonly thought to have evolved from a quadrupedal
terrestrial precursor, yet some recent paleontological evidence suggests
that adaptations for bipedalism arose in an arboreal context. However, the
adaptive benefit of arboreal bipedalism has been unknown. Here we show that
it allows the most arboreal great ape, the orangutan, to access supports too
flexible to be negotiated otherwise. Orangutans react to branch flexibility
like humans running on springy tracks, by increasing knee and hip extension,
whereas all other primates do the reverse. Human bipedalism is thus less an
innovation than an exploitation of a locomotor behavior retained from the
common great ape ancestor.

____

Gibbons walk bipedally over branches, orangs do this sometime it now
appears, so perhaps the early apes already did this, but all this does not
explain why no monkeys do this. In any case, it seems to suggest that the
early hominoids were already (parttime) bipedal: wading? branch-hanging?
(from which walking bipedally over branches as in gibbons & orangs & other
apes could have evolved).

Orangs don't knuckle-walk: on the ground (seldom), they walk on the "heels"
of the hand: they fist-walk (with the fingers +-flexed, usu.on the lateral
side of the hand) or palm-walk (with the fingers +-extended).
KWing (Pan & Gorilla) is very derived, in fact more derived than
(short-legged) bipedality as seen in all hominoids now & then. KWing (on
the dorsal side of the hand) can't evolve directly from palmigrady (on the
ventral side of the hand), so there must have been an intermediary phase:
short-legged bipedality in early hominoids, eg, for wading in swamp forests,
where the fossil apes are found. Arm-hanging (alone) does not explain KWing,
since gibbons & orangs & human infants palm-walk.