Re: Lucy had gorilla-like fingers


alandarwinvanarsdale
 

In modern biology - systematics Australopithecus can not be ancestral to Homo. Because all known Australopithecus and Homo are derived relative to each other (not suitable ancestors either way). Australopithecus grades into African great apes, especially Gorilla (such as the bipedal female proto Gorilla Sahelanthropus). While Homo floresiensis is much closer to the Asiatic great ape Lufengpithecus than any known African great ape. Also see the most detailed cladistic study done on great ape relationships with Homo (Schwartz et al) orangutans are closer morphologically to Homo than any known African great ape. ________________________________________________________________________________________________________________________________________________The results of this paper are neither unexpected (in modern systematics) or previsouly unknown. Australopithecus are mosaics of unique derived traits for their clade, traits from Homo (presumably by gene flow) and derived African great ape traits (presumably also from interbreeding with great apes to which they overlapped in range) The origin of Pan in fact is evidenced to be Sub-Sahara, though there is no evidence the origin of Homo or Homo sapiens was Sub-Sahara. 


On Thu, Sep 22, 2022 at 7:20 AM Gareth Morgan <garethmorgan@...> wrote:
the hominin had shorter thumbs than was thought, with proportions more
closely resembling gorillas.

these results suggest Au.afarensis could not produce
precision grips with the same efficiency as Hs

Non sequitur. Look at this hand. What could it not do?



Lucy could have played the flute...



... manipulated delicate objects...



or picked up the tiniest insect.




The "thumbs on gorillas' feet are much bigger than the "fingers". 



Does that mean the "precision grip" of a gorilla's feet is more "efficient" than H. sap's hands?

G.


From: AAT@groups.io <AAT@groups.io> on behalf of Marc Verhaegen <m_verhaegen@...>
Sent: Thursday, September 22, 2022 3:32 PM
To: AAT@groups.io <AAT@groups.io>
Subject: [AAT] Lucy had gorilla-like fingers
 
Human ancestor had small thumbs

Fossil analysis reveals that a Hs ancestor would have made a terrible
hitch-hiker.
Past reconstructions of the hands of the hominin Au.afarensis assigned
scattered bones to individuals & single fingers.
Campbell Rolian (Univ.Calgary Canada) & Adam Gordon (SU NY Albany)
re-analysed an assembly of Au.afarensis bones to better account for
uncertainties in the fossil record.
Their results suggest:
the hominin had shorter thumbs than was thought, with proportions more
closely resembling gorillas.
Although Au.afarensis may have been able to bring the tips of its
fingers & thumbs together, its thumbs were not long enough for the
precision grip that later hominins used to craft stone tools.
Am. J. Phys. Anthropol. 152, 393–406 (2013)

Reassessing manual proportions in Australopithecus afarensis
Campbell Rolian & Adam D Gordon 2013 AJPA doi org/10.1002/ajpa.22365
Am J Phys Anthropol 152:393–406, 2013.

Previous analyses of hand morphology in Au.afarensis have concluded: it
had modern human-like manual proportions: rel.long thumbs & short
fingers.
These conclusions (based on the A.L.333 composite fossil assemblage from
Hadar) are premised on the ability to assign phalanges to a single
individual, and to the correct side & digit.
Neither assignment is secure, however, given the taphonomy & sample
composition at A.L.333.

Our re-sampling approach (incl. the entire assemblage of complete hand
elements at Hadar) takes into account uncertainties in identifying
phalanges by individual, side & digit nr.
This provides the most conservative estimates of manual proportions in
Au.afarensis.
We re-sampled hand long bone lengths in Au.afarensis & extant hominoids,
we obtained confidence limits for distributions of manual proportions in
the latter.
Results confirm: intrinsic manual proportions in Au.afarensis are
dissimilar to Pan & Pongo,
but manual proportions in Au.afarensis often fall at the upper end of
the distribution in Gorilla, very lower end in Homo:
disproportionately short thumbs & long medial digits in Homo.
This suggests:
manual proportions in Au.afarensis (particularly metacarpal proportions)
- were not as derived towards Homo as previously described,
- rather are intermediate between gorillas & humans.
Functionally, these results suggest Au.afarensis could not produce
precision grips with the same efficiency as Hs,
this may in part account for the absence of lithic technology in this
fossil taxon.

____

Only anthropocentric PAs believe Lucy was our ancestor.
Lucy was obviously a fossil relative of Gorilla.
Google "aaquarboreal ancestors".





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