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Author Topic:   New Species of Homo Discovered: Homo naledi
Dr Adequate
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Posts: 15468
Joined: 07-20-2006
Member Rating: 3.8


Message 106 of 163 (768665)
09-12-2015 9:15 PM
Reply to: Message 104 by Faith
09-12-2015 8:43 PM


Dem Bones
The skeleton shows no difference in the length of the thumb from the fingers.

Once more. Here is the paper describing the find.

It contains this photograph of an H. naledi hand:

They describe it as follows: "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 ..."

It has a long thumb, like a modern human or like Australopithicus sediba, and unlike a chimp. It is not, however, as long as the fingers.

What it seems you are trying to do is gauge the length of the thumb by looking at a photograph where the bones of the hand have been taken apart and scattered on a table. (Close-up below.)

But obviously this has nothing to do with the actual proportions of the hand. If you dismembered my hand, then you could send the distal phalange of my thumb through the mail until it was thousands of miles from my trapezium, and yet this would not prove anything about my anatomy.

Edited by Dr Adequate, : No reason given.


This message is a reply to:
 Message 104 by Faith, posted 09-12-2015 8:43 PM Faith has responded

Replies to this message:
 Message 107 by NosyNed, posted 09-12-2015 9:34 PM Dr Adequate has not yet responded
 Message 109 by Faith, posted 09-12-2015 9:38 PM Dr Adequate has responded

  
NosyNed
Member
Posts: 8751
From: Canada
Joined: 04-04-2003
Member Rating: 10.0


Message 107 of 163 (768667)
09-12-2015 9:34 PM
Reply to: Message 106 by Dr Adequate
09-12-2015 9:15 PM


Thumb length
What it seems you are trying to do is gauge the length of the thumb by looking at a photograph...

No, worse than that I think. She is looking at her own hand and not realizing that about half the thumb length is buried in flesh and muscle.


This message is a reply to:
 Message 106 by Dr Adequate, posted 09-12-2015 9:15 PM Dr Adequate has not yet responded

Replies to this message:
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Faith
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Posts: 23953
Joined: 10-06-2001
Member Rating: 1.0


Message 108 of 163 (768670)
09-12-2015 9:37 PM
Reply to: Message 107 by NosyNed
09-12-2015 9:34 PM


Re: Thumb length
I see my hand as like the radiograph of a human hand.

Edited by Faith, : No reason given.


This message is a reply to:
 Message 107 by NosyNed, posted 09-12-2015 9:34 PM NosyNed has responded

Replies to this message:
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Faith
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Posts: 23953
Joined: 10-06-2001
Member Rating: 1.0


Message 109 of 163 (768671)
09-12-2015 9:38 PM
Reply to: Message 106 by Dr Adequate
09-12-2015 9:15 PM


Re: Dem Bones
Put it this way: THERE IS NO WAY TO TELL WHAT SORT OF HAND THAT IS FROM THE WAY THE BONES ARE ARRANGED.
This message is a reply to:
 Message 106 by Dr Adequate, posted 09-12-2015 9:15 PM Dr Adequate has responded

Replies to this message:
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Dr Adequate
Member
Posts: 15468
Joined: 07-20-2006
Member Rating: 3.8


Message 110 of 163 (768672)
09-12-2015 9:39 PM
Reply to: Message 109 by Faith
09-12-2015 9:38 PM


Re: Dem Bones
Put it this way: THERE IS NO WAY TO TELL WHAT SORT OF HAND THAT IS FROM THE WAY THE BONES ARE ARRANGED.

But in this picture, there is a way.


This message is a reply to:
 Message 109 by Faith, posted 09-12-2015 9:38 PM Faith has not yet responded

  
NosyNed
Member
Posts: 8751
From: Canada
Joined: 04-04-2003
Member Rating: 10.0


Message 111 of 163 (768673)
09-12-2015 9:40 PM
Reply to: Message 108 by Faith
09-12-2015 9:37 PM


Re: Thumb length
Faith writes:

The skeleton shows no difference in the length of the thumb from the fingers. My own hand shows a large difference. I have a much shorter thumb relative to my fingers than the one belonging to the skeleton has.

How odd, my thumb it very close to exactly the same length as my longest finger.
(I'd show it to you but admin might spank me)


This message is a reply to:
 Message 108 by Faith, posted 09-12-2015 9:37 PM Faith has responded

Replies to this message:
 Message 112 by Faith, posted 09-12-2015 10:30 PM NosyNed has responded

  
Faith
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Posts: 23953
Joined: 10-06-2001
Member Rating: 1.0


Message 112 of 163 (768680)
09-12-2015 10:30 PM
Reply to: Message 111 by NosyNed
09-12-2015 9:40 PM


Re: Thumb length
Yeah, I knew you couldn't tell one from another.
This message is a reply to:
 Message 111 by NosyNed, posted 09-12-2015 9:40 PM NosyNed has responded

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RAZD
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Posts: 18240
From: the other end of the sidewalk
Joined: 03-14-2004
Member Rating: 2.9


(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; Almécija 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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This message is a reply to:
 Message 112 by Faith, posted 09-12-2015 10:30 PM Faith has not yet responded

  
ringo
Member
Posts: 12815
From: frozen wasteland
Joined: 03-23-2005
Member Rating: 2.6


(1)
Message 114 of 163 (768750)
09-13-2015 3:50 PM
Reply to: Message 109 by Faith
09-12-2015 9:38 PM


Re: Dem Bones
Faith writes:

Put it this way: THERE IS NO WAY TO TELL WHAT SORT OF HAND THAT IS FROM THE WAY THE BONES ARE ARRANGED.


It's hard to tell what you're trying so hard to be wrong about. That hand looks a lot like mine.
This message is a reply to:
 Message 109 by Faith, posted 09-12-2015 9:38 PM Faith has not yet responded

  
jar
Member
Posts: 28422
From: Texas!!
Joined: 04-20-2004
Member Rating: 2.6


(1)
Message 115 of 163 (768755)
09-13-2015 4:30 PM
Reply to: Message 109 by Faith
09-12-2015 9:38 PM


Re: Dem Bones
There may well be no way for you tell what sort of hand it is from the way the bones are arranged but that does not preclude those who are not ignorant of anatomy, archaeology and anthropology to tell what sort of hand it is.

Fortunately the evidence is overwhelming that evolution is a fact, that the earth is billions of years old and that humans have been around for millions of years.


Anyone so limited that they can only spell a word one way is severely handicapped!

This message is a reply to:
 Message 109 by Faith, posted 09-12-2015 9:38 PM Faith has not yet responded

  
DevilsAdvocate
Member (Idle past 448 days)
Posts: 1548
Joined: 06-05-2008


(2)
Message 116 of 163 (768775)
09-13-2015 10:20 PM
Reply to: Message 71 by Faith
09-11-2015 11:52 AM


Re: incredible creationists
That artist's concept is ridiculous.

So you are totally unaware of forensic science. Over the past several decades forensic scientists and forensic artists have used facial reconstruction techniques to help match unidentified skeleton remains to missing persons around the globe. This is the same technology and methods used to help determine the physical appearance of these fossil remains.

http://lancasteronline.com/news/local/dead-men-do-tell-tales-forensic-artist-tries-to-find/article_8be3d75a-70ad-11e4-aa26-fb02c72d68f9.html

If the bones suggest that kind of physiognomy it's not a human being.

Agreed, it isn't a human being. But it isn't a chimpanzee, gorilla, or orangutan either. It is closer in resemblance to human beings than to chimpanzees, gorillas and orangutans. But it is clearly neither. So what is it, Faith?

Speciation is just a point in the microevolution where genetic differences caused by the reduction in genetic variability make breeding impossible.

You have it backwards. A reduction in genetic variability (aka organisms become more gentically similar) typically by itself does NOT cause speciation within that same group. Just think about it. Something has to cause a group of animals to become more genetically similar. That is usually a bottleneck of some sort i.e. a reduction in population caused by natural or human activity. Speciation usually occurs when a group of organisms is isolated (either physically or some other mechanism) from another group of the same species. Because these two groups are now genetically separate and little to no genetic information is shared between these two groups occur (through mating). Therefor, they drift apart genetically until at some point they differ so much genetically that they are no longer able to mate with each other. Thus they are now two separate species.

Evolution is that simple. And no there is no difference between micro and macro evolution. One is just a view of evolution up close and the other is from a distance; just the same as view a leaf of a tree with magnifying glass and the other viewing the entire tree from a distance.

It's still the same creature. The idea that it's a new species is completely bogus, just an assumption based on the theory.

Species by definition is a group of organisms that differ genetically to such a degree from organisms that they cannot mate and have offspring. Not sure what you find problematic about this concept.

Edited by DevilsAdvocate, : No reason given.

Edited by DevilsAdvocate, : No reason given.

Edited by DevilsAdvocate, : No reason given.


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NosyNed
Member
Posts: 8751
From: Canada
Joined: 04-04-2003
Member Rating: 10.0


Message 117 of 163 (768781)
09-13-2015 11:27 PM
Reply to: Message 112 by Faith
09-12-2015 10:30 PM


Re: Thumb length
So as I understand it we have some difference of opinion about thumb lengths, right?

You suggest your thumb is much shorter than your fingers. Anatomists say human thumbs are long. When I measure my thumb and fingers I find my thumb to be long.

There is a difference and your answer is: "Yeah, I knew you couldn't tell one from another." It sounds like you don't like where this is going.

So where are we? Are human thumbs long compared to other primates or not? How long is your thumb compared to your longest finger?


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 Message 112 by Faith, posted 09-12-2015 10:30 PM Faith has not yet responded

  
Meddle
Member
Posts: 156
From: Scotland
Joined: 05-08-2006


Message 118 of 163 (768808)
09-14-2015 8:05 AM
Reply to: Message 83 by Faith
09-12-2015 12:15 AM


Sorry for not replying sooner, was working this weekend. Will reply to the issues on the hand the now, and discuss about the skulls in a later post.

As for the hands, human hands have short thumbs and those don’t.

Apologies for any confusion, I realise now I should have included captions with the thumbnails I posted and been more clear in my description. The first picture is the bones of the human hand with the bones labelled which, I hoped, would make it easier to discuss the details, although I had been swithering over using the X-ray image Dr Adequate used showing the metacarpals embedded in the soft tissue of the palm. Second picture was obviously H.naledi and third was a Chimpanzee for comparison.

Yes human thumbs are shorter than the rest of our fingers because of the lack of the intermediate phalanx. However, the point I was trying to make was the proportions of the bones in the hand of H.naledi is a lot closer to Humans than it is to chimps. The metacarpals of the Chimp are elongated making the overall size of their hand much longer, giving the impression that the thumb is shorter. With that in mind, can you say from those thumbnails which structures of the hand of H.naledi is more like that of Chimps than humans?


This message is a reply to:
 Message 83 by Faith, posted 09-12-2015 12:15 AM Faith has responded

Replies to this message:
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Faith
Member
Posts: 23953
Joined: 10-06-2001
Member Rating: 1.0


(1)
Message 119 of 163 (768814)
09-14-2015 9:56 AM
Reply to: Message 118 by Meddle
09-14-2015 8:05 AM


Thank you for being polite.

Essentially then the hand is a human hand, even though the bones as arranged on the skeleton are indecipherable. Human hands differ from one another just as everything else about us differs from one to another, and such a small difference doesn't make this skeleton anything other than a human being.

Edited by Faith, : No reason given.


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NosyNed
Member
Posts: 8751
From: Canada
Joined: 04-04-2003
Member Rating: 10.0


Message 120 of 163 (768818)
09-14-2015 10:30 AM
Reply to: Message 118 by Meddle
09-14-2015 8:05 AM


So that's the difference
I am not counting the palm as part of the "finger" length. That is incorrect then? And then my thumb if very short compared to my fingers as Faith says. But thumbs are still long in humans compared to other primates?
This message is a reply to:
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Replies to this message:
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