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Author Topic:   New Species of Homo Discovered: Homo naledi
RAZD
Member (Idle past 1404 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


Message 68 of 163 (768544)
09-11-2015 10:58 AM
Reply to: Message 1 by Percy
09-10-2015 7:59 AM


technicalities
Thanks for the technical paper link, Percy. All I had see to date was a video on facebook that showed the difficulty of navigating the cave.
The page link is: This Face Changes the Human Story. But How?
quote:
The bones were superbly preserved, and from the duplication of body parts, it soon became clear that there was not one skeleton in the cave, but two, then three, then five ... then so many it was hard to keep a clear count. ...
There were some 1,550 specimens in all, representing at least 15 individuals. Skulls. Jaws. Ribs. Dozens of teeth. A nearly complete foot. A hand, virtually every bone intact, arranged as in life. Minuscule bones of the inner ear. Elderly adults. Juveniles. Infants, identified by their thimble-size vertebrae. Parts of the skeletons looked astonishingly modern. But others were just as astonishingly primitivein some cases, even more apelike than the australopithecines. We’ve found a most remarkable creature, Berger said. His grin went nearly to his ears.
... But these teeth weren’t like anything the scientists in the tooth booth had ever seen. Some features were astonishingly humanlikethe molar crowns were small, for instance, with five cusps like ours. But the premolar roots were weirdly primitive. ...
The same schizoid pattern was popping up at the other tables. A fully modern hand sported wackily curved fingers, fit for a creature climbing trees. The shoulders were apish too, and the widely flaring blades of the pelvis were as primitive as Lucy’sbut the bottom of the same pelvis looked like a modern human’s. The leg bones started out shaped like an australopithecine’s but gathered modernity as they descended toward the ground. The feet were virtually indistinguishable from our own.
When you read the articles and see repeated references to the fossils showing a mixture of primitive and derived characteristics, you can see the evolution of traits found in our skeletons ... and when you go to the technical paper these aspects are laid out in detail.
You'll have to page down to the video. It also says, "The NOVA/National Geographic Special, Dawn of Humanity, premieres Sept. 16, 2015, at 9 p.m. ET/8 p.m. CT on PBS in the United States and is streaming online now.
Another good source is:
South African Cave Yields Strange Bones Of Early Human-Like Species
quote:
He notes that only a small section of the cave chamber has been excavated, and it looks like many more bones are down there.
"There is the potential for thousands of specimens in that cave," says Wood. "Intellectually, it's a real puzzle. And I think it's going to take scientists quite a time to get their heads around what the real significance of these discoveries is."
So ... watch this space, more to come ...
The combination of derived modern traits with primitive ancestral traits is what shows this to be a transitional species, fitting between Australopithicus and Homosapien fossils. It will be interesting to see how they date this find.
Enjoy
Edited by RAZD, : added comment

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RAZD
Member (Idle past 1404 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


Message 72 of 163 (768548)
09-11-2015 12:03 PM
Reply to: Message 70 by Faith
09-11-2015 11:48 AM


to fossil or not to fossil, that is the question ...
... All THOSE fossilized. ...
And what about the ones that did not fossilize? The bones in this cave are not fossilized ...
How can some bones fossilize and some bones not fossilize when they are all subjected to the same flood condition that you claim universally causes (somehow) the fossilization.
Enjoy

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RAZD
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Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


(1)
Message 84 of 163 (768560)
09-12-2015 7:03 AM
Reply to: Message 83 by Faith
09-12-2015 12:15 AM


Time
What evidence do you have that any particular skull in that chart microevolved from the one preceding it? I look at that collection and see an arrangement that's most likely artificial. Some overzealous evolutionist just put them in the order that seems to suggest evolution from one type to the next, but what's the evidence of that? I suspect there's none. (For one thing why should there be such a neat sequence that seems to demonstrate how we got a bigger brain than our apish ancestor anyway? Isn't that rather teleological and doesn't that violate a basic idea of how evolution supposedly works?)
Time.
The first skull is a modern chimpanzee skull for comparison, the rest are arranged chronologically from oldest to youngest.
29 Evidences for Macroevolution: Part 1
quote:
29 Evidences for Macroevolution
Part 1:
The Unique Universal Phylogenetic Tree
Figure 1.4.4. Fossil hominid skulls. Some of the figures have been modified for ease of comparison (only left-right mirroring or removal of a jawbone). (Images 2000 Smithsonian Institution.)
(A) Pan troglodytes, chimpanzee, modern
(B) Australopithecus africanus, STS 5, 2.6 My
(C) Australopithecus africanus, STS 71, 2.5 My
(D) Homo habilis, KNM-ER 1813, 1.9 My
(E) Homo habilis, OH24, 1.8 My
(F) Homo rudolfensis, KNM-ER 1470, 1.8 My
(G) Homo erectus, Dmanisi cranium D2700, 1.75 My
(H) Homo ergaster (early H. erectus), KNM-ER 3733, 1.75 My
(I) Homo heidelbergensis, "Rhodesia man," 300,000 - 125,000 y
(J) Homo sapiens neanderthalensis, La Ferrassie 1, 70,000 y
(K) Homo sapiens neanderthalensis, La Chappelle-aux-Saints, 60,000 y
(L) Homo sapiens neanderthalensis, Le Moustier, 45,000 y
(M) Homo sapiens sapiens, Cro-Magnon I, 30,000 y
(N) Homo sapiens sapiens, modern

Note that (B) and (C) are the same species\age, as are (D) and (E); that (J), (K) and (L) are all neanders, and that (M) is archaic human while (N) is modern human.
Note further that any denial of the ages shown is empty until you have explained the evidence in Age Correlations and An Old Earth, Version 2 No 1 for an old earth and the methods of dating artifacts.
The fossils sorted by age is what shows the evolutionary trending from more ape-like to modern human, it is not arbitrary, artificial or just some whim of some purported "overzealous evolutionist" as anyone with the same evidence, derived independently for each skull, would place them in the same order.
Until we have better dates for Homo naledi all we can say is that they appear to be between (C) and (D) at this time.
Finally please note that this is not intended as a linear line of development, rather it is a sampling of the hominids from those periods, and like the neanders, some could be cousins. And those cousins may also have interbred as we now know happened with neanders.
Enjoy
Edited by RAZD, : .

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 Message 83 by Faith, posted 09-12-2015 12:15 AM Faith has replied

Replies to this message:
 Message 91 by Faith, posted 09-12-2015 12:57 PM RAZD has replied

  
RAZD
Member (Idle past 1404 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


(3)
Message 94 of 163 (768626)
09-12-2015 1:21 PM
Reply to: Message 91 by Faith
09-12-2015 12:57 PM


Re: Time
Sorry, I don't accept your dating methods. Lot of "adjusting" goes on to make things fit the theory.
And curiously, as I said in Message 84: " ... any denial of the ages shown is empty until you have explained the evidence in Age Correlations and An Old Earth, Version 2 No 1 for an old earth and the methods of dating artifacts."
So until you actually show that the dating methods are actually erroneous, prone to error, or manipulated by some vast conspiracy, your comment is taken as plain denial of actual evidence to the contrary.
Enjoy

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RAZD
Member (Idle past 1404 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


Message 99 of 163 (768634)
09-12-2015 3:28 PM
Reply to: Message 98 by Admin
09-12-2015 2:14 PM


Moving on -- brain size and brain development
See the original paper for the details I just related and more: Homo naledi, a new species of the genus Homo from the Dinaledi Chamber, South Africa
That paper lists a number of traits that are primitive (ie more ape-like, and similar to australopiths) and traits that are derived -- modified from earlier species.
This involves iirc, curved finger bones, shape inside skull, hips and feet.
One of the things I find interesting is the size of the brain, and the comments regarding the conception of burial or care of the dead. There are no other animal bones in the cave (except one owl) so the best explanation is that they were deposited there by the naledi.
And one of the reasons I find this interesting is (a) the reasoning ability of chimps, and (b) Homo floriensis had similar smallish brains
quote:
Homo floresiensis: ... Examination of the remains shows members of the species stood just 1 metre tall and had a brain no bigger than a grapefruit.
Doing a "google scholar" on Homo floresiensis brain size I get:
quote:
The Brain of LB1, Homo floresiensis
Abstract
The brain of Homo floresiensis was assessed by comparing a virtual endocast from the type specimen (LB1) with endocasts from great apes, Homo erectus, Homo sapiens, a human pygmy, a human microcephalic, specimen number Sts 5 (Australopithecus africanus), and specimen number WT 17000 (Paranthropus aethiopicus). Morphometric, allometric, and shape data indicate that LB1 is not a microcephalic or pygmy. LB1's brain/body size ratio scales like that of an australopithecine, but its endocast shape resembles that of Homo erectus. LB1 has derived frontal and temporal lobes and a lunate sulcus in a derived position, which are consistent with capabilities for higher cognitive processing.
So we are talking the same approximate size, and what may matter more than size is whether we will see derived frontal and temporal lobes "... consistent with capabilities for higher cognitive processing."
So we will need more analysis or more fossils.
abe
From the technical paper it appears that cranial volume in nalide is larger than floresiensis:
This makes more information on the frontal and temporal lobe development to ascertain cognitive ability of even greater interest.
/abe
Enjoy
Edited by RAZD, : abe section

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RAZD
Member (Idle past 1404 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


Message 101 of 163 (768655)
09-12-2015 7:22 PM
Reply to: Message 100 by Faith
09-12-2015 6:36 PM


not to thumb my nose at this issue, but ...
I understand all that. The hand does not have a short thumb, as clearly shown in the pictures by Dr. A despite his ridiculous attempt to pretend otherwise..
I'm confused by this whole spat: it seems to me that both of you are saying that the thumb of naledi is not short, as it is for chimps (by comparison, though it may be more a matter of finger metacarpal lengths than thumb bones) ...
Can you cite the post where he says the thumb is short?

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RAZD
Member (Idle past 1404 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


(1)
Message 113 of 163 (768701)
09-13-2015 8:44 AM
Reply to: Message 112 by Faith
09-12-2015 10:30 PM


Re: Thumb length
For the record this is what the technical paper says about the hand:
quote:
Homo naledi, a new species of the genus Homo from the Dinaledi Chamber, South Africa
Abstract
... H. naledi has humanlike manipulatory adaptations of the hand and wrist. ...
... Based on this wide range of specimens from a single site, Berger et al. describe Homo naledi as being similar in size and weight to a small modern human, with human-like hands and feet. ...
Dinaledi hand 1 (H1) is a nearly complete (missing only the pisiform) right hand, found articulated in association, comprising specimens U.W. 101-1308 to −1311, −1318 to −1321, −1325 to −1329, −1351, −1464, and −1721 to −1732 (Figure 6; Supplementary file 1). ...
Hand 1.
Palmar view on left; dorsal view on right. This hand was discovered in articulation and all bones are represented except for the pisiform. The proportions of digits are humanlike and visually apparent, as are the expanded distal apical tufts on all digits, the robust pollical ray, and the unique first metacarpal morphology.
Hand (H1)
H. naledi possesses a combination of primitive and derived features not seen in the hand of any other hominin. H1 is differentiated from the estimated intrinsic hand proportions of Au. afarensis in having a relatively long thumb ((Mc1 + PP1)/(Mc3 + PP3 + IP3)) (Rolian and Gordon, 2013; Almcija and Alba, 2014). It is further distinguished from Au. afarensis, Au. africanus, and Au. sediba in having a well-developed crest for both the opponens pollicis and first dorsal interosseous muscles, a trapezium-scaphoid joint that extends onto the scaphoid tubercle, a relatively large and more palmarly-positioned capitate-trapezoid joint, and/or a saddle-shaped Mc5-hamate joint. H. naledi also differs from Au. sediba in that it lacks mediolaterally narrow Mc2-5 shafts (Kivell et al., 2011). Manual morphology of Au. garhi is currently unknown.
H1 is distinguished from H. habilis in having a deep proximal palmar fossa with a well-developed ridge distally for the insertion of the flexor pollicis longus muscle on the first distal phalanx, and a more proximodistally oriented trapezium-second metacarpal joint. It also differs from both H. habilis and H. floresiensis by having a relatively large trapezium-scaphoid joint that extends onto the scaphoid tubercle, and from H. floresiensis in having a boot-shaped trapezoid with an expanded palmar surface, and a relatively large and more palmarly-positioned capitate-trapezoid joint (Tocheri et al., 2005, 2007; Orr et al., 2013).
H1 is dissimilar to hand remains attributed to Paranthropus robustus/early Homo from Swartkrans (Susman, 1988; Susman et al., 2001) in having a relatively small Mc1 base and proximal articular facet, a saddle-shaped Mc5-hamate joint, and more curved proximal and intermediate phalanges of ray 2—5.
Manual morphology of H. rudolfensis is currently unknown, and that of H. erectus is largely unknown. Still, H1 differs from a third metacarpal attributed to H. erectus s. l., as well as from Homo neanderthalensis and H. sapiens by lacking a styloid process (Ward et al., 2013).
H1 is further distinguished from H. neanderthalensis and H. sapiens by its relatively small facets for the Mc1 and scaphoid on the trapezium, its low angle between the Mc2 and Mc3 facets on the capitate, and by its long and curved proximal and intermediate phalanges on rays 2—5.
H1 is differentiated from all known hominins in having a Mc1 that combines a mediolaterally narrow proximal end and articular facet with a mediolaterally wide distal shaft and head, a dorsopalmarly flat and strongly asymmetric (with an enlarged palmar-lateral protuberance) Mc1 head, and the combination of an overall later Homo-like carpal morphology combined with proximal and intermediate phalanges that are more curved than most australopiths. H1 also differs from all other known hominins except H. neanderthalensis in having non-pollical distal phalanges with mediolaterally broad apical tufts (relative to length).
Note for clarity sake: this is just the right hand, shown palm up and palm down in the picture, not a right and a left hand.
Now I don't expect you to understand a lot of the detailed descriptions of bones and shapes and their relative importance -- I know I don't -- but I DO expect you to understand that the scientists who wrote and read this article do. This is an example of the fine detail that scientists use to compare ALL fossils.
In fact I expect you will only take two things away from all of this information: (1) that "H1 is differentiated from the estimated intrinsic hand proportions of iAu. afarensis in having a relatively long thumb ... " and (2) that the hand is different from all other species used for comparison ... in the fine details, and that you will take this to support a YEC position of "separate" creation or your position of "normal" diversity in populations -- it doesn't. The simple fact that we can compare these bones in such fine detail is because the evidence supports relationships of the sort that only evolution predicts: a mixture (mosaic) of inherited primitive and (mutated, evolved) derived features fixed in a matrix of time and space.
Enjoy
Edited by RAZD, : hand
Edited by RAZD, : ...

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RAZD
Member (Idle past 1404 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


(2)
Message 123 of 163 (768847)
09-14-2015 12:39 PM
Reply to: Message 122 by NosyNed
09-14-2015 11:10 AM


Yes, that's the hand difference, now let's look at the foot?
This is the picture that Malcolm posted previously of a modern human hand:
Note that the thumb is missing an Intermediate Phalange, a trait common to hominids (includes apes).
If you compare bone lengths you can see that the thumb bones compare to the little finger bone lengths.
This is the previously posted Homo naledi hand:
As you can see it has traits very similar to the modern human hand diagram.
As noted in a previous post though, when you look at the fine detail (hard to see from these pictures), there are differences that the scientists find significant: the naledi bones have more curvature (intermediate between australopiths and later homos) and the joint structure is different.
Faith says that these minor differences fall within the normal variation of our species, based on her well documented knowledge of human hand bones
Thus she says it is human.
Now let's look at the foot, and see how similar that is:
quote:
Homo naledi, a new species of the genus Homo from the Dinaledi Chamber, South Africa
Abstract
Homo naledi ... also exhibits a humanlike foot and lower limb. ...
Holotype
... Dinaledi foot 1 (F1) is a partial foot skeleton missing only the medial cuneiform and the phalanges of rays II—V. Foot 1 is composed of specimens U.W. 101-1322, −1417 to −1419, −1439, −1443, −1456 to −1458, −1551, −1553, −1562, and −1698.
Figure 9. Foot 1 in (A) dorsal view; and (B) medial view.
(C) Proximal articular surfaces of the metatarsals of Foot 1, shown in articulation to illustrate transverse arch structure. Scale bar = 10 cm.
Differential diagnosis
Foot (F1)
The foot of H. naledi differs from the pedal remains of Au. afarensis, Au. africanus, and Au. sediba in having a calcaneus with a weakly developed peroneal trochlea. F1 also differs from Au. afarensis in having a higher orientation of the calcaneal sustentaculum tali. F1 can be further distinguished from pedal remains attributed to Au. africanus in having a higher talar head and neck torsion, a narrower Mt1 base, a dorsally expanded Mt1 head, and greater proximolateral to distomedial orientation of the lateral metatarsals. The H. naledi foot can be further differentiated from the foot of Au. sediba in having a proximodistally flatter talar trochlea, a flat subtalar joint, a diagonally oriented retrotrochlear eminence and a plantar position of the lateral plantar process of the calcaneous, and dorsoplantarly flat articular surface for the cuboid on the Mt4 (Zipfel et al., 2011). Pedal remains of Au. garhi are currently unknown, and those of P. robustus are too poorly known to allow for comparison.
The H. naledi foot can be distinguished from the foot of H. habilis by the presence of a flatter, non-sloping trochlea with equally elevated medial and lateral margins, a narrower Mt1 base, greater proximolateral to distomedial orientation of the lateral metatarsals, and a metatarsal robusticity ratio of 1 > 5 > 4 > 3 > 2. Pedal morphology in H. rudolfensis is currently unknown, and that of H. erectus is too poorly known to allow for comparison. The H. naledi foot can be distinguished from the foot of H. floresiensis by a longer hallux and shorter second through fifth metacarpals relative to hindfoot length, and higher torsion of the talar head and neck.
The foot of H. naledi can be distinguished from the foot of H. sapiens only by its flatter lateral and medial malleolar facets on the talus, its low angle of plantar declination of the talar head, its lower orientation of the calcaneal sustentaculum tali, and its gracile calcaneal tuber.
It would appear that the naledi foot is also very similar to modern human, maybe even more similar than the hand.
And it looks like hands (adapted for tool use?) and feet (adapted for bipedal upright locomotion) were well established in the early Homo evolution.
Perhaps for comparison we could have some australopith and modern human feet images posted?
Enjoy
Edited by RAZD, : clrty

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Replies to this message:
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RAZD
Member (Idle past 1404 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


(3)
Message 125 of 163 (768892)
09-14-2015 6:44 PM
Reply to: Message 124 by Diomedes
09-14-2015 3:18 PM


Re: Yes, that's the hand difference, now let's look at the foot?
... there is a Nova special on this Wednesday (check your local stations) called 'Dawn of Humanity'. It will be discussing this recent South African find along with other discoveries.
Including the discovery of Au. sediba.
And as mentioned in Message 68 it can be watched on-line at
The NOVA/National Geographic Special, Dawn of Humanity, ... is streaming online now (click this link).
It's an hour, and a very well spent hour.
Enjoy
(I did)

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RAZD
Member (Idle past 1404 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


(5)
Message 126 of 163 (768893)
09-14-2015 6:51 PM
Reply to: Message 125 by RAZD
09-14-2015 6:44 PM


Another source of information from NCSE
Another source:
Homo nalediAnother Awesome Twig on the Human Family Tree, Part 1
This find is a real treasure trove.
More to come.
Enjoy

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RAZD
Member (Idle past 1404 days)
Posts: 20714
From: the other end of the sidewalk
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Message 127 of 163 (768964)
09-15-2015 10:40 AM
Reply to: Message 123 by RAZD
09-14-2015 12:39 PM


Now here's an interesting exercise -- comparing hand and foot bones ...
Here's a diagram of a foot's bone structure beside the hand picture from Malcolm:
Curiously I notice several things:
  • metatarsals instead of metacarpals
  • proximal phalanges and distal phalanges on both on all toes\thumb\fingers
  • intermediate phalanges only on little toes\fingers, missing on both thumb and big toe
  • the carpal bones also match up to the cuniform and cuboid bones, with two toes meeting at the cuboid bone in similar fashion to the two fingers that meet and a single carpal
In older hominid fossils the big toe is slightly separated from the other toes -- intermediate between the hand like foot of an ape and the modern human foot, as demonstrated by the bones.
Enjoy
ps - iirc there was a discussion of australopithicus feet on one of the 'Lucy' threads, complete with matching it to the Laetoli footprints. I'll try to find it later.
Edited by RAZD, : clrty
Edited by RAZD, : sp

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RAZD
Member (Idle past 1404 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


Message 128 of 163 (769140)
09-16-2015 9:11 PM
Reply to: Message 127 by RAZD
09-15-2015 10:40 AM


Re: Now here's an interesting exercise -- comparing hand and foot bones ...
ps - iirc there was a discussion of australopithicus feet on one of the 'Lucy' threads, complete with matching it to the Laetoli footprints. I'll try to find it later.
So I looked through {composite\Lucy\Little-Foot\Australopithicus} was bipedal and found
Message 20: But if you think "little foot" was an unexpected find, then compare this 1935 prediction with "little foot" (same article):
quote:

A find that matches a prediction based on evolution.
The clearest pictures of the Laetoli footprints that I could find are:
Another article on matching footprints to fossils is
The Laetoli Footprint Trail: 3D reconstruction from texture; archiving, and reverse engineering of early hominin gait ...
Unfortunately that last link is broken.
The important thing to observe though is that the critical alignment of the big toe metacarpal onto the cuneiform bone is written in the fossil and it shows the slight splay of the big toe angled away from the other bones in a position intermediate between that of later hominids and that of apes.
Now some may think that the "Little Foot" fossil evidence is a little scant to extrapolate to the full footprint, but there are others ... it will take a little more digging to find them.
Enjoy

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This message is a reply to:
 Message 127 by RAZD, posted 09-15-2015 10:40 AM RAZD has seen this message but not replied

  
RAZD
Member (Idle past 1404 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


Message 130 of 163 (769204)
09-17-2015 8:27 AM
Reply to: Message 129 by NoNukes
09-17-2015 6:05 AM


Getting ahead?
Now that everyone is on the same page about the hand, and possibly even about the foot, the interesting thing is how different much of the rest of the skeleton is from modern humans.
It is fascinating to me how "modern" the foot is, that there has been so little further development of this part of the skeleton. This with the hand shows how macroevolution is not an all-at-once change, but an accumulation of changes over generations. The intermediates are a mosaic of ancestral traits and new derived traits.
... Because this is clearly a finding of a formerly living being with human-like hands that was not a homo sapiens.
I had hoped to get to the pelvic girdle next as that would tie back to discussions on Australopithicus but I did not see a reconstructed pelvis in the paper. Perhaps when they go back and dig further they might find one. We do have femurs, an abundance of femurs, but I don't think those will be as convincing.
That pretty well leaves us with the head\skull\cranial reconstruction:
quote:
Homo naledi, a new species of the genus Homo from the Dinaledi Chamber, South Africa
Abstract
Homo naledi is a previously-unknown species of extinct hominin discovered within the Dinaledi Chamber of the Rising Star cave system, Cradle of Humankind, South Africa. This species is characterized by body mass and stature similar to small-bodied human populations but a small endocranial volume similar to australopiths. Cranial morphology of H. naledi is unique, but most similar to early Homo species including Homo erectus, Homo habilis or Homo rudolfensis. While primitive, the dentition is generally small and simple in occlusal morphology.
... the skull had several unique features, it had a small braincase that was most similar in size to other early hominin species that lived between four million and two million years ago. ...
Holotype
Dinaledi Hominin 1 (DH1) comprises the partial calvaria, partial maxilla, and nearly complete mandible of a presumed male individual, ...
Figure 2. Holotype specimen of Homo naledi, Dinaledi Hominin 1 (DH1).
U.W. 101-1473 cranium in (A) posterior and (B) frontal views (frontal view minus the frontal fragment to show calvaria interior). U.W. 101-1277 maxilla in (C) medial, (D) frontal, (E) superior, and (F) occlusal views. (G) U.W. 101-1473 cranium in anatomical alignment with occluded U.W. 101-1277 maxilla and U.W. 101-1261 mandible in left lateral view. U.W. 101-1277 mandible in (H) occlusal, (I) basal, (J) right lateral, and (K) anterior views. Scale bar = 10 cm.
Paratypes
Dinaledi Hominin 2 (DH2) is a partial calvaria that preserves parts of the frontal, left and right parietals, right temporal, and occipital (Figure 3; Supplementary file 1). Dinaledi Hominin 3 (DH3) is a partial calvaria of a presumed female individual that preserves parts of the frontal, left parietal, left temporal, and sphenoid (Figure 4, Supplementary file 1). Dinaledi Hominin 4 (DH4) is a partial calvaria that preserves parts of the right temporal, right parietal, and occipital (Figure 3; Supplementary file 1). Dinaledi Hominin 5 (DH5) is a partial calvaria that preserves part of the left temporal and occipital (Figure 3; Supplementary file 1). U.W. 101-377 is a mandibular fragment that preserves dental anatomy in an unworn state; at present it cannot be definitively associated with any of these Dinaledi Hominin (DH) individuals, and indeed might represent another individual (Figure 5; Supplementary file 1). These cranial specimens agree closely in nearly all morphological details where they overlap in areas preserved except those we interpret as related to sex.
Figure 3. Cranial paratypes.
(A) DH2, right lateral view. (B) DH5, left lateral view. (C) DH4, right lateral view. (D) DH4, posterior view. Scale bar = 10 cm.
Figure 4. Paratype DH3.
(A) Frontal view. (B) Left lateral view, with calvaria in articulation with the mandible (U.W. 101-361). (C) Basal view. Mandible in (D) medial view; (E) occlusal view; (F) basal view. DH3 was a relatively old individual at time of death, with extreme tooth wear. Scale bar = 10 cm.
Figure 5. U.W. 101-377 mandible.
(A) Lateral view; (B) medial view; (C) basal view; (D) occlusal view. (D) The distinctive mandibular premolar morphology with elongated talonids in unworn state. Scale bar = 2 cm.
That is the fossil evidence.
Due to the volume of information I am going to break this into three posts -- the fossil evidence (here), the comparison to other fossils, and the reconstruction of the skull.
Enjoy

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Replies to this message:
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RAZD
Member (Idle past 1404 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


(1)
Message 131 of 163 (769217)
09-17-2015 12:12 PM
Reply to: Message 130 by RAZD
09-17-2015 8:27 AM


Re: Getting ahead? (pt 2)
Moving on to the comparisons then:
quote:
Homo naledi, a new species of the genus Homo from the Dinaledi Chamber, South Africa
Differential diagnosis
This comprehensive differential diagnosis is based upon cranial, dental and postcranial characters. The hypodigms used for other species are detailed in the ‘Materials and methods’. ...
Cranium, mandible, and dentition (DH1, DH2, DH3, DH4, DH5, U.W. 101-377)
The cranium of H. naledi does not have the well-developed crest patterns that characterize Australopithecus garhi (Asfaw et al., 1999) and species of the genus Paranthropus, nor the derived facial morphology seen in the latter genus. The mandible of H. naledi is notably more gracile than those of Paranthropus. Although maxillary and mandibular incisors and canines of H. naledi overlap in size with those of Paranthropus, the post-canine teeth are notably smaller than those of Paranthropus and Au. garhi, with mandibular molars that are buccolingually narrow.
H. naledi differs from Australopithecus afarensis and Australopithecus africanus in having a pentagonal-shaped cranial vault in posterior view, sagittal keeling, widely spaced temporal lines, an angular torus, a deep and narrow digastric fossa, an external occipital protuberance, an anteriorly positioned root of the zygomatic process of the maxilla, a broad palate, and a small canine jugum lacking anterior pillars. The anterior and lateral vault of H. naledi differs from Au. afarensis and Au. africanus in exhibiting only slight post-orbital constriction, frontal bossing, a well-developed supraorbital torus with a well-defined supratoral sulcus, temporal lines that are positioned on the posterior rather than the superior aspect of the supraorbital torus, a root of the zygomatic process of the temporal that is angled downwards approximately 30 relative to the Frankfort Horizontal (FH) and which begins its lateral expansion above the mandibular fossa rather than the EAM, a mandibular fossa that is positioned medial to the wall of the temporal squame, a small postglenoid process that contacts the tympanic, a coronally oriented petrous, and a small and obliquely oriented EAM. The H. naledi mandible exhibits a more gracile symphysis and corpus, a more vertically inclined symphysis, a slight mandibular incurvation delineating a faint mental trigon, and a steeply inclined posterior face of the mandibular symphysis without a post incisive planum. The incisors of H. naledi overlap in size with some specimens of Au. africanus, though the canines and post-canine dentition are notably smaller, with relatively narrow buccolingual dimensions of the mandibular molars. The maxillary I1 lacks a median lingual ridge and exhibits a broad and uninflated lingual cervical prominence, the lingual mesial and distal marginal ridges do not merge onto the cervical prominence in the maxillary I2, the mandibular canine exhibits only a weak lingual median ridge and a broad and uninflated lingual cervical prominence, and the buccal grooves on the maxillary premolars are only weakly developed. H. naledi exhibits a small and isolated Carabelli's feature in the maxillary molars, unlike the more prominent and extensive Carabelli's feature of Australopithecus. Moreover, the H. naledi mandibular molars possess small, mesiobuccally restricted protostylids that do not intersect the buccal groove, differing from the typically enlarged, centrally positioned protostylids that intersect the buccal groove in Australopithecus.
The cranium of H. naledi differs from Australopithecus sediba (Berger et al., 2010) in exhibiting sagittal keeling, a more pronounced supraorbital torus and supratoral sulcus, a weakly arched supraorbital contour with rounded lateral corners, an angular torus, a well-defined supramastoid crest, a curved superior margin of the temporal squama, a root of the zygomatic process of the temporal that is angled downwards approximately 30 relative to FH, a flattened nasoalveolar clivus, weak canine juga, an anteriorly positioned root of the zygomatic process of the maxilla, and a relatively broad palate that is anteriorly shallow. The H. naledi mandible (DH1) has a mental foramen positioned superiorly on the corpus that opens posteriorly, unlike the mid-corpus height, more laterally opening mental foramen of Au. sediba. The maxillary and mandibular teeth of H. naledi are smaller than those of Au. sediba, with mandibular molars that are buccolingually narrow. The lingual mesial and distal marginal ridges do not merge onto the cervical prominence in the maxillary I2, the paracone of the maxillary P3 is equal in size to the protocone, the protoconid and metaconid of the mandibular molars are equally mesially positioned, and the lingual cusps of the molars are positioned at the occlusobuccal margin while the buccal cusps are positioned slightly lingual to the occlusobuccal margin. Also, Au. sediba shares with other australopiths a protostylid that is centrally located and which intersects the buccal groove of the lower molars, unlike the small and mesiobuccally restricted protostylid that does not intersect the buccal groove in H. naledi.
The cranium of H. naledi differs from Homo habilis in exhibiting sagittal keeling, a weakly arched supraorbital contour, temporal lines that are positioned on the posterior rather than the superior aspect of the supraorbital torus, an angular torus, an occipital torus, only slight post-orbital constriction, a curved superior margin of the temporal squama, a suprameatal spine, a weak crista petrosa, a prominent Eustachian process, a small EAM, weak canine juga, and an anteriorly positioned root of the zygomatic process of the maxilla. Mandibles attributed to H. habilis show a weakly inclined, shelf-like post incisive planum with a variably developed superior transverse torus, unlike the steeply inclined posterior face of the mandibular symphysis of H. naledi, which lacks both a post incisive planum or superior transverse torus. The H. naledi mandible (DH1) has a mental foramen positioned superiorly on the corpus that opens posteriorly, while the mental foramen of H. habilis is at mid-corpus height and opens more laterally. The maxillary and mandibular dentitions of DH1 are smaller than typical for H. habilis. The mandibular P3 of H. naledi is more molarized and lacks the occlusal simplification seen in H. habilis; it has a symmetrical occlusal outline, and multiple roots (two roots: mesiobuccal and distal) not seen in H. habilis. The molars of H. naledi lack crenulation, secondary fissures, and supernumerary cusps that are common to H. habilis. The protoconid and metaconid of the mandibular molars are equally mesially positioned.
The cranium of H. naledi differs from Homo rudolfensis by its smaller cranial capacity, and by exhibiting frontal bossing, a post-bregmatic depression, sagittal keeling, a well-developed supraorbital torus delineated by a distinct supratoral sulcus, temporal lines that are positioned on the posterior rather than the superior aspect of the supraorbital torus, an occipital torus, an external occipital protuberance, only slight post-orbital constriction, a small postglenoid process, a weak crista petrosa, a laterally inflated mastoid process, a canine fossa, incisors that project anteriorly beyond the bi-canine line, and a shallow anterior palate. As in H. habilis, mandibles attributed to H. rudolfensis show a weakly inclined, shelf-like post incisive planum with a variably developed superior transverse torus, unlike the steeply inclined posterior face of the mandibular symphysis of DH1, the latter of which lacks either a post incisive planum or superior transverse torus. The mandibular symphysis and corpus of H. naledi are more gracile than those attributed to H. rudolfensis, and the H. naledi mandible (DH1) has a mental foramen positioned superiorly on the corpus that opens posteriorly, unlike the mid-corpus height, more laterally opening mental foramen of H. rudolfensis. The maxillary and mandibular dentition of H. naledi is smaller than that of most specimens of H. rudolfensis, with only KNM-ER 60000 and KNM-ER 62000 appearing similar in size for some teeth (Leakey et al., 2012). The molars of H. naledi lack crenulation, secondary fissures, or supernumerary cusps common in H. rudolfensis. The buccal grooves of the maxillary premolars are weak in H. naledi, and the protoconid and metaconid of the mandibular molars are equally mesially positioned.
H. naledi lacks the typically distinctive long and low cranial vault of Homo erectus, as well as the metopic keeling that is typically present in the latter species. H. naledi also differs from H. erectus in having a distinct external occipital protuberance in addition to the tuberculum linearum, a laterally inflated mastoid process, a flat and squared nasoalveolar clivus, and an anteriorly shallow palate. The parasagittal keeling that is present between bregma and lambda in H. naledi (DH1 and DH3) is less marked than often occurs in H. erectus, including in small specimens such as KNM-ER 42700 and the Dmanisi cranial sample. Also unlike most specimens of H. erectus, H. naledi has a small vaginal process, a weak crista petrosa, a marked Eustachian process, and a small EAM. The mandible of H. erectus shows a moderately inclined, shelf-like post incisive planum terminating in a variably developed superior transverse torus, differing from the steeply inclined posterior face of the H. naledi mandibular symphysis, which lacks both a post incisive planum or a superior transverse torus. The mental foramen is positioned superiorly and opens posteriorly in DH1, unlike the mid-corpus height, more laterally opening mental foramen of H. erectus. The maxillary and mandibular incisors and canines of H. naledi are smaller than typical of H. erectus. The mandibular P3 of H. naledi is more molarized and lacks the occlusal simplification seen in H. erectus, they reveal a symmetrical occlusal outline, and multiple roots (2R: MB+D) not typically seen in H. erectus. Furthermore, the molars of H. naledi lack crenulation, secondary fissures, or supernumerary cusps common in H. erectus.
H. naledi lacks the reduced cranial height of Homo floresiensis, and displays a marked angular torus and parasagittal keeling between bregma and lambda that is absent in the latter species. H. naledi further has a flat and squared nasoalveolar clivus, unlike the pronounced maxillary canine juga and prominent pillars of H. floresiensis. The mandible of H. floresiensis shows a posteriorly inclined post incisive planum with superior and inferior transverse tori, differing from the steeply inclined posterior face of the H. naledi mandibular symphysis, which lacks both a post incisive planum or a superior transverse torus. Dentally, H. naledi is distinguishable from H. floresiensis by the mesiodistal elongation and extensive talonid of the mandibular P4, and the lack of Tomes' root on the mandibular premolars. The molar size gradient of H. naledi follows the M1 < M2 < M3 pattern, unlike the M3 < M2 < M1 pattern in H. floresiensis, and the mandibular molars are relatively mesiodistally long and buccolingually narrow compared to those of H. floresiensis.
H. naledi differs from Middle Pleistocene (MP) and Late Pleistocene (LP) Homo (here we include specimens sometimes attributed to the putative Early Pleistocene taxon Homo antecessor, and MP Homo heidelbergensis, Homo rhodesiensis, as well as archaic Homo sapiens and Neandertals) in exhibiting a smaller cranial capacity. H. naledi has its maximum cranial width in the supramastoid region, rather than in the parietal region. It has a clearly defined canine fossa (similar to H. antecessor), a shallow anterior palate, and a flat and a squared nasoalveolar clivus. H. naledi lacks the bilaterally arched and vertically thickened supraorbital tori found in MP and LP Homo. H. naledi also differs in exhibiting a root of the zygomatic process of the temporal that is angled downwards approximately 30 relative to FH, a projecting entoglenoid process, a weak vaginal process, a weak crista petrosa, a prominent Eustachian process, a laterally inflated mastoid process, and a small EAM. The H. naledi mandible tends to be more gracile than specimens of MP Homo. The mandibular canine retains a distinct accessory distal cuspulid not seen in MP and LP Homo. Molar cuspal proportions for H. naledi do not show the derived reduction of the entoconid and hypoconid that characterizes MP and LP Homo. The mandibular M3 is not reduced in DH1, thus revealing an increasing molar size gradient that contrasts with reduction of the M3 in MP and LP Homo.
H. naledi differs from H. sapiens in exhibiting small cranial capacity, a well-defined supraorbital torus and supratoral sulcus, a root of the zygomatic process of the temporal that is angled downwards approximately 30 relative to FH, a large and laterally inflated mastoid with well-developed supramastoid crest, an angular torus, a small vaginal process, a weak crista petrosa, a prominent Eustachian process, a small EAM, a flat and squared nasoalveolar clivus, and a more posteriorly positioned incisive foramen. The H. naledi mandible shows a weaker, less well-defined mentum osseum than H. sapiens, as well as a slight inferior transverse torus that is absent in humans. The mental foramen is positioned superiorly in H. naledi, unlike the mid-corpus height mental foramen of H. sapiens. The mandibular canine possesses a distinct accessory distal cuspulid not seen in H. sapiens. Molar cuspal proportions for H. naledi do not show the derived reduction of the entoconid and hypoconid that characterizes H. sapiens. The mandibular M3 is not reduced in H. naledi, thus revealing an increasing molar size gradient that contrasts with reduction of the M3 in H. sapiens.
Again, this is a lot of detail, and difficult to follow if you are not into anatomy.
Suffice it to say, that this kind of detail is there, and that it -- especially the head\brain -- is what distinguishes one species from another.
In the next post we can look at the reconstructed skull and what it means for the brain inside.
Enjoy

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This message is a reply to:
 Message 130 by RAZD, posted 09-17-2015 8:27 AM RAZD has replied

Replies to this message:
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RAZD
Member (Idle past 1404 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


Message 135 of 163 (769242)
09-18-2015 9:55 AM
Reply to: Message 134 by NoNukes
09-18-2015 1:28 AM


Re: Getting ahead?
Can we get back to the topic? You can take your sole complaint to the complaint thread ...
Enjoy

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