Re: Lucy = slow

On Sep 28, 4:29 pm, Lee Olsen <paleoc...@xxxxxxxxxxx> wrote:
On Sep 28, 3:59 pm, nickname <alas_my_lo...@xxxxxxxxx> wrote:



On Sep 28, 6:04 am, Lee Olsen <paleoc...@xxxxxxxxxxx> wrote:

On Sep 27, 2:09 pm, nickname <alas_my_lo...@xxxxxxxxx> wrote:

On Sep 27, 5:54 am, Lee Olsen <paleoc...@xxxxxxxxxxx> wrote:

On Sep 26, 11:21 pm, nickname <alas_my_lo...@xxxxxxxxx> wrote:

On Sep 26, 4:27 am, "Mario Petrinovich"

<mario.petrinov...@xxxxxxxxxxx> wrote:
Gerrit Hanenburg:

http://www.timesonline.co.uk/tol/news/uk/science/article2434423.ece

Wait a minute, this article says that Lucy couldn't run because she
didn't have an achilles tendon. That's interesting. What would count
as evidence that A. afarensis didn't have an achilles tendon, as even
chimps have it? True, in chimps the tendon is much shorter than in
humans, but in both taxa the gastrocnemius muscle inserts through the
achilles tendon (= tendo calcaneus) on the posterior aspect
(tuberosity) of the calcaneus. So, the phylogenetic bracket in this
case suggests that A. afarensis also had an achilles tendon. Any other
evidence? Sure, the A.L. 333-8 calcaneus is described as "The inferior
half of the tuberosity is roughened for the insertion of the tendo
calcaneus" and A.L. 333-37 as "The tuberosity is roughened on its
inferior half for insertion of the calcaneal tendon" (Latimer et al.
1982. Hominid Tarsal, Metatarsal, and Phalangeal Bones Recovered From
the Hadar Formation: 1974-1977 Collections. Am. J. Phys. Anth. 57:
701-719). So, Lucy did have an achilles tendon.
Now, running is a function of stride frequency and stride length.
That's why even bipedally displaying chimps and bipedal Basilisk
lizards can run, and pretty fast too if only for short distances.
So, in the light of the above information it's likely that Lucy was
able to run, but probably not efficiently and for short distances if
she lacked the elongation of the achilles tendon (in humans circa 65%
of the total gastrocnemius length).
And of course, this research is also a fine piece of evidence that
humans were made for running. Why else would evolve an elongated
achilles tendon if not for storing elastic energy for locomotion?
Comparative evidence shows that this exactly the kind of mechanism
other mammals use to increase the efficiency of their run
(particularly well developed in ricochetal animals such as kangeroos).

Excellent, Gerrit.
I definitely think that Lucy had Achilles tendon. Without Achilles
tendom creature could not live on the ground. Now, the problem is, why Lucy
developed Achilles tendon in the first place? You mentioned other animals
that have developed Achilles tendon. I would say that all those animals
should develop Achilles tendon BEFORE being able to run bipedally.
This is the problem. You have to develop Achilles tendom BEFORE
going bipedal. This fits excellently into my Cliff Aquatic Ape Scenario. --
Mario Petrinovich

Since gibbons, siamangs and humans have a well developed achilles
tendon, but the great apes (which are typically more terrestrial than
the lesser apes), lack a well developed achilles tendon,

Except Hss and probably He. What about the differences?

and the
lesser apes do not climb cliffs nor run about on savannas, it would
seem the mystery has yet to be solved.

No really,

http://tinyurl.com/262xup
"Apparently, adaptations for arboreal locomotion have not constrained
the terrestrial locomotor abilities of gibbons. This may indicate that
the step from an arboreal ancestral ape to a terrestrial, upright
bipedal hominin might not be difficult and that structural
specializations are not a prerequisite for adopting a (non-habitual)
bipedal gait."

Same argument for orangs was cited on sap a while back.

I propose that the bipedal last common ancestor of the lesser apes,
great apes and Homo (about 20ma) had a well developed achilles tendon,
and it was lost in the great apes due to their reversion to a more
typical forest floor quadrupedal gait, knucklewalking and fist walking
while on the ground. Since the lesser apes and Homo have never done
that, the primitive tendon arrangement and bipedality has remained
unchanged.

Richmond and Strait suggest otherwise.

This is obvious when comparing the smooth bpal gait of the gibbon with
the awkward gait of the chimp. Even the spider monkey when carrying an
egg walks smoother bipedally than any great ape.

Size matters, Hulk Hogan would not make a very good ballerina.

Small gibbons and humans share these 4 traits:
1) chin 2) well developed achilles tendon 3) loss of laryngeal air sac
4) Song (not call hoots)

Great apes and Lucy (apiths) lack chins, lack well developed achilles
tendons and possess laryngeal air sacs and tend to call hoot.

Yep, see 'The Red Ape' for all the similarities between us and orangs,
what about it?

Lee your are so lost in loonyland I doubt it's worth the trouble.

Says the lying troll who doesn't know the difference between

the Mediterranean and a savanna.

Message-ID: <1190616231.506617.300...@xxxxxxxxxxxxxxxxxxxxxxxxxxxx>

Great apes diverged from the bipedal pattern,

Richmond and Strait suggest otherwise.

so their achilles
shrunk.

Says who?

Of course we share some other traits with the great apes,
we're closely related to them.

Well, duh.

Lee
arguing with yourself, assures you win every time.
snipping everything except your smartaleck answers leaves little of
value. Relevance and continuity please.

Says the lying troll who doesn't know the difference between

the Mediterranean and a savanna.

Message-ID: <1190616231.506617.300...@xxxxxxxxxxxxxxxxxxxxxxxxxxxx>

Watch out for the trollee!

.

Relevant Pages

  • Re: Lucy = slow
    ... as evidence that A. afarensis didn't have an achilles tendon, ... in chimps the tendon is much shorter than in ... but the great apes (which are typically more terrestrial than ... the primitive tendon arrangement and bipedality has remained ...
    (sci.anthropology.paleo)
  • Re: Lucy = slow
    ... as evidence that A. afarensis didn't have an achilles tendon, ... in chimps the tendon is much shorter than in ... but the great apes (which are typically more terrestrial than ... the primitive tendon arrangement and bipedality has remained ...
    (sci.anthropology.paleo)
  • Re: Lucy = slow
    ... as evidence that A. afarensis didn't have an achilles tendon, ... in chimps the tendon is much shorter than in ... but the great apes (which are typically more terrestrial than ... the primitive tendon arrangement and bipedality has remained ...
    (sci.anthropology.paleo)
  • Re: Lucy = slow
    ... as evidence that A. afarensis didn't have an achilles tendon, ... in chimps the tendon is much shorter than in ... but the great apes (which are typically more terrestrial than ... the primitive tendon arrangement and bipedality has remained ...
    (sci.anthropology.paleo)
  • Re: Lucy = slow
    ... as evidence that A. afarensis didn't have an achilles tendon, ... in chimps the tendon is much shorter than in ... but the great apes (which are typically more terrestrial than ... the primitive tendon arrangement and bipedality has remained ...
    (sci.anthropology.paleo)