https://www.nature.com/articles/ncomms9431

The hand of H.naledi is very similar to that of
modern humans, with two major differences:
a) it has an extraordinarily long and powerful
thumb;
b) Its fingers are curved, like those of
australopiths, but otherwise resemble those
of modern humans.

Anyone want to suggest likely reasons?

I've changed my views on this a couple of
times, and will probably modify them again
before posting here.

Paul Crowley wrote:

> https://www.nature.com/articles/ncomms9431
>
> The hand of H.naledi is very similar to that of
> modern humans, with two major differences:
> a) it has an extraordinarily long and powerful
> thumb;
> b) Its fingers are curved, like those of
> australopiths, but otherwise resemble those
> of modern humans.
>
> Anyone want to suggest likely reasons?
>
> I've changed my views on this a couple of
> times, and will probably modify them again
> before posting here.

#1. So much @#$% has been spewed about Naledi STARTING
WITH THE FIRST WORDS that I've sometimes wondered if it
really existed at all, or if it was all a PR campaign grafted on an
extinct species of ape...

Remember the "Modern Features" in the brain? The "Prepared
Burials?" Or what about the 2 million year (plus) age?

#1a. Naledi is representative of the lack of science. For instance,
I've complained elsewhere about it but, a documentary on the
excavations was produced and in it they didn't even take rudimentary
precautions against contamination. They handled remains in the
open air and with bare hands, uncovered faces.

It's difficult to come to any reasonable determinations when you are
dependent upon information from people who are less interested in
facts than they are headlines.

#2. The hands, if they're real, would be great for swimming. Modern
hand paddles are "Computer designed" and what not, but the vintage
ones increased surface area primarily by increasing length:

https://i.ebayimg.com/images/g/n0UAAOSwglxhQiVg/s-l300.jpg

https://www.ebay.com/itm/304147899133?chn=ps&mkevt=1&mkcid=28

#3. Hybridization is a very real possibility.

I've postulated that humans invented Chimpanzees. That, Pan began
as an upright walking tool user but also spread into the forests. Then
as the Homo line competed with them (preyed upon them) more and
more of their evolutionary pressures were on the forest dwellers,
exclusively. So in this model, we would expect some of the last of the
non-forest dwellers to exhibit forest (arboreal) adaptations, as the
breeding with the forest group would be asymmetrical, heavily favoring
the forest group.

It's not linear but, it is the sort of thing we can reasonably expect to
see.

So they could be arboreal adaptations even if they aren't associated with
an arboreal population. AND THEN there's the fact that they were climbing
in this cave!

-- --

https://jtem.tumblr.com/search/AGW

On Thursday, February 10, 2022 at 5:09:24 PM UTC-5, Paul Crowley wrote:
> https://www.nature.com/articles/ncomms9431
>
> The hand of H.naledi is very similar to that of
> modern humans, with two major differences:
> a) it has an extraordinarily long and powerful
> thumb;
> b) Its fingers are curved, like those of
> australopiths, but otherwise resemble those
> of modern humans.
>
> Anyone want to suggest likely reasons?
>
> I've changed my views on this a couple of
> times, and will probably modify them again
> before posting here.

A sediba: remarkably long gracile thumb
H naledi: long robust thumb
Homo: long thumb vs African apes, extremely long vs orangutan & gibbon

Tree sleeper, ground/waterside forager, no knucklewalking, elephant hitchhiker.

On Friday, February 11, 2022 at 9:58:49 AM UTC, Pandora wrote:

>> https://www.nature.com/articles/ncomms9431
>>
>> The hand of H.naledi is very similar to that of
>> modern humans, with two major differences:
>> a) it has an extraordinarily long and powerful
>> thumb;
>> b) Its fingers are curved, like those of
>> australopiths, but otherwise resemble those
>> of modern humans.
>>
>>Anyone want to suggest likely reasons?
>
> Already in the paper.

Not so. Or not in any meaningful manner:
This is typical of the technically detailed
verbiage, which lacks all sense of purpose
(What were these hands FOR . . ?) :

"This distinctive mosaic of morphology has yet to be observed
in any other hominin taxon and suggests the use of the hand
for arboreal locomotion in combination with forceful precision
manipulation typically used during tool-related behaviours."

Firstly, the 'arboreal locomotion' doesn't
apply since that's the norm for other
primates and their hands invariably have
long thin fingers.

Secondly, they appear to have lived in
dolomitic caves, and few trees grow on
their surface landscapes -- certainly no
large ones, and no forests. So it's hard
to see that they'd have much need for
'arboreal locomotion'.

Thirdly, if any hominin had a need for
'forceful precision manipulation typically
used during tool-related behaviours', it
would be later and bigger ones, especially
humans and neanderthals. But naledi's
thumb is (proportionately) much longer
and stronger than any seen later or
elsewhere.

" . . The H. naledi pollical distal phalanx (n=2) is large and robust"

Why?

On Saturday, February 12, 2022 at 6:49:15 PM UTC-5, Paul Crowley wrote:
> On Friday, February 11, 2022 at 9:58:49 AM UTC, Pandora wrote:
>
> >> https://www.nature.com/articles/ncomms9431
> >>
> >> The hand of H.naledi is very similar to that of
> >> modern humans, with two major differences:
> >> a) it has an extraordinarily long and powerful
> >> thumb;
> >> b) Its fingers are curved, like those of
> >> australopiths, but otherwise resemble those
> >> of modern humans.
> >>
> >>Anyone want to suggest likely reasons?
> >
> > Already in the paper.
> Not so. Or not in any meaningful manner:
> This is typical of the technically detailed
> verbiage, which lacks all sense of purpose
> (What were these hands FOR . . ?) :
>
> "This distinctive mosaic of morphology has yet to be observed
> in any other hominin taxon and suggests the use of the hand
> for arboreal locomotion in combination with forceful precision
> manipulation typically used during tool-related behaviours."
>
> Firstly, the 'arboreal locomotion' doesn't
> apply since that's the norm for other
> primates and their hands invariably have
> long thin fingers.
>
> Secondly, they appear to have lived in
> dolomitic caves, and few trees grow on
> their surface landscapes -- certainly no
> large ones, and no forests. So it's hard
> to see that they'd have much need for
> 'arboreal locomotion'.
>
> Thirdly, if any hominin had a need for
> 'forceful precision manipulation typically
> used during tool-related behaviours', it
> would be later and bigger ones, especially
> humans and neanderthals. But naledi's
> thumb is (proportionately) much longer
> and stronger than any seen later or
> elsewhere.
>
> " . . The H. naledi pollical distal phalanx (n=2) is large and robust"
>
> Why?

Sexual selection?

On Sunday, February 13, 2022 at 3:46:47 PM UTC, Pandora wrote:

>>> Already in the paper.
>>
>> Not so. Or not in any meaningful manner:
>> This is typical of the technically detailed
>> verbiage, which lacks all sense of purpose
>
> It's thoroughly empirical, comparative and functional anatomy.
> Apparently way above your level of expertise and comprehension.
> Where and when did you study primate functional anatomy?

Standard PA's 'level of expertise and
comprehension" can be judged from
their routine 'assessment' that the
curvature of hominin fingers before
homo came from arboreal behaviour,
in particular sleeping in trees! If they
had slept in trees, they'd have been
in them for more than 12 hours out
of 24, and required much the same
kinds of hands as those hominoids
that really do spend most of their
time in trees -- e.g. chimps.

And, of course, when why or how
they ever ceased to sleep in trees are
topics far beyond their 'level of
expertise'.

>> (What were these hands FOR . . ?) :

> It says right here:

When you are unable or unwilling to
deal honestly with the obvious questions
you are obliged to retreat into verbiage.

>> "This distinctive mosaic of morphology has yet to be observed
>> in any other hominin taxon and suggests the use of the hand
>> for arboreal locomotion in combination with forceful precision
>> manipulation typically used during tool-related behaviours."
>>
>> Firstly, the 'arboreal locomotion' doesn't
>> apply since that's the norm for other
>> primates and their hands invariably have
>> long thin fingers.
>
> But "forceful precision manipulation typically used during
> tool-related behaviours" is not typical of primates. That's where the
> mosaic morphology comes into view, because you can't do that with long
> thin fingers and a short thumb.

'Mosaic' is always such a handy word.
Of course, it would usually be more
accurate and honest to say "we
haven't a clue".

>> Secondly, they appear to have lived in
>> dolomitic caves, and few trees grow on
>> their surface landscapes -- certainly no
>> large ones, and no forests. So it's hard
>> to see that they'd have much need for
>> 'arboreal locomotion'.
>
> And don't recall any reconstruction of the paleoenvronment of Homo
> naledi outside their depositional environment.

The geomorphology of dolomitic limestone
is very stable: little or no water on the
surface; trees only in those isolated places
where the roots can reach down into
openings to get water -- usually where a
cave roof has collapsed.

It seems unlikely that there was open
water (or significant food resources) within
5-6 km of the Dinaledi chamber. Yet the
corpses were hardly carried that far,
suggesting that the group/tribe/family
resided in it, or in nearby caves, travelling
several km for daily foraging.

>> Thirdly, if any hominin had a need for
>> 'forceful precision manipulation typically
>> used during tool-related behaviours', it
>> would be later and bigger ones, especially
>> humans and neanderthals. But naledi's
>> thumb is (proportionately) much longer
>> and stronger than any seen later or
>> elsewhere.
>>
>> " . . The H. naledi pollical distal phalanx (n=2) is large and robust"
>
> As far as I can see from fig.2 in Kivell et al. relative thumb length
> in H. naledi falls within the range of modern male Homo sapiens, and
> is shorter than in Australopithecus sediba (2mya).
> https://www.nature.com/articles/ncomms9431/figures/2

It's around the 98th percentile -- not
usually describable as 'within the range'.
Modern male human hands are highly
variable, in size and shape. The paper
suggests that -- in this measure -- the
hands of h.naledi were all much the
same:

" . . The base and proximal articular facet of the pollical
metacarpal are remarkably small relative to its length,
both radioulnarly and dorsopalmarly in Hand 1 and in
the six additional pollical metacarpals . ."

> The same figure also shows that the most obvious difference is between
> hominins and Pan/Gorilla, not among hominins.

Of course. And since PA has got almost
nowhere in explaining the differences
between hominins and pan/gorilla, it
would be foolish to think it could do
anything with intra-hominin variations.

On Saturday, February 19, 2022 at 5:45:12 PM UTC, Pandora wrote:

> And this is confirmed by the rest of the upper limb morphology, such
> as a markedly cranially-oriented glenoid fossa and very oblique
> scapular spine, reflecting the habitually overhead posture of the arm
> in suspensory behaviour to assist with efficient arm elevation:
> https://www.sciencedirect.com/science/article/abs/pii/S004724841630135X

Homo did not spring from nowhere.
Its ancestors swung in trees. There
have been no strong selective forces
that would have displaced this
anatomy

>> If they
>> had slept in trees, they'd have been
>> in them for more than 12 hours out
>> of 24, and required much the same
>> kinds of hands as those hominoids
>> that really do spend most of their
>> time in trees -- e.g. chimps.
>
> Chimps also use their hands in terrestrial locomotion and much less
> for forceful precision manipulation. You get different kinds of
> trade-off.

Chimps were one example of the fairly
standard pattern of long-fingered
hands seen in primates. Some
primates use their hands in terrestrial
locomotion, but they don't lose their
long fingers. The standard PA
conception of everyday lives of early
hominins includes very little in the way
of 'forceful precision manipulation';
That would be a small fraction of their
behaviour if they brought the
supposed night-time requirements
into consideration. What were they
actually doing during the day? What
were they doing MUCH MORE than
chimps, such that they needed very
different hands?

>> It seems unlikely that there was open
>> water (or significant food resources) within
>> 5-6 km of the Dinaledi chamber. Yet the
>> corpses were hardly carried that far,
>> suggesting that the group/tribe/family
>> resided in it, or in nearby caves, travelling
>> several km for daily foraging.
>
> The many cercopithecids at sites such as Sterkfontein and Swartkrans
> indicate a significant arboreal component, while the valley bottom may
> have retained standing water year-round, supporting more extensive
> tree cover.

The cercopithecids at Sterkfontein
and Swartkrans are predominantly
terrestrial ones (e.g. baboons). I see
those sites are being places where
such animals died rather than where
they lived -- similar to the La Brea tar
pits. They were deadly traps for
thirsty animals finding themselves
lost on unfamiliar open country.

> I'm sure you have a fantastic idea about hand function in H. naledi,
> on the same level as marine hominins. Or is it just rock climbing with
> ropes and anchors?

Do I detect the glimmer of an active
brain cell?

Paul Crowley wrote:

> Homo did not spring from nowhere.
> Its ancestors swung in trees. There
> have been no strong selective forces
> that would have displaced this
> anatomy

So your position is that Chimps evolved from humans?

Because Chimps evolved from upright walkers who all
most certainly used tools. And if humans evolved from
an arboreal ancestor while Chimps did not, that would
require that Chimps evolved from humans.

Actually, you did get the relationship correct though
perhaps the timing wrong. Chimps did split off from,
away from our line, not the other way around. Not only
did Chimps evolve from an upright walker but they have
the more derived hand!

https://gwtoday.gwu.edu/human-hands-less-evolved-chimp-hands

You know hands, don't you? Everyone looks at the more
derived, arboreally adapted hand and pretends they're
seeing a more primitive hand...

Just something to chew on.

-- --

https://jtem.tumblr.com/tagged/gun%20control/page/2

Op donderdag 10 februari 2022 om 23:09:24 UTC+1 schreef Paul Crowley:
> https://www.nature.com/articles/ncomms9431
> The hand of H.naledi is very similar to that of
> modern humans, with 2 major differences:
> a) it has an extraordinarily long & powerful thumb;
> b) Its fingers are curved cf australopiths, but otherwise resemble Hs.

> Anyone want to suggest likely reasons?
> I've changed my views on this a couple of
> times, and will probably modify them again
> before posting here.

Pauli, Pauli, just google "Australopithecus naledi PPT".
Our hands are generally more primitive than those of P or G:
no knuckle-walking:
KWing evolved lately in parallel in P // G.
IOW, naledi was Pan naledi, fossil subgenus Australopithecus,
google "ape human evolution made easy PPT Verhaegen".

littor...@gmail.com wrote:

> Pauli, Pauli, just google "Australopithecus naledi PPT".
> Our hands are generally more primitive than those of P or G:
> no knuckle-walking:
> KWing evolved lately in parallel in P // G.
> IOW, naledi was Pan naledi, fossil subgenus Australopithecus,
> google "ape human evolution made easy PPT Verhaegen".

I agree. Well, Naledi is on the Pan(*) side of the divide. I can't see how
anyone in their right mind can call Naledi "Homo" without also
making an argument for reclassifying Chimps as Homo...

(*) Just as happy calling them Australopithecus naledi. Take your pick.

-- --

https://jtem.tumblr.com/post/158530861591