Guest Cricket Posted June 21, 2017 Posted June 21, 2017 (edited) DWA: I'm not so sure naledi isn't an australopithecine. There is almost no physical marker that points in another direction. Homo seems to rest entirely on the joint burial, falling once again into that very human trap of presuming "only humans do x." WSA: Right. It is precisely this need to lay a genus and species on a hunk of rock that drives it. Labels matter and we can't help ourselves. I'd be happy with "Fossil #3" and just describe it. When #4 shows up, tell us how it is different. Since the time you both wrote that, there has been publication of the type specimen’s description and analysis: http:// https://elifesciences.org/articles/09560 It is a lengthy and very thorough paper, including comparative cranial and dental measurements, and serves to illustrate the difference between what is written in the popular press on the one hand, and what is written in the scholarly publications on the other, as I mentioned the other day in a different post. While I haven’t had a chance to do a full and careful reading yet, I did see that the authors identified numerous features that they concluded indicated its placement in Homo, and they discussed how H. naledi differs from a variety of hominin taxa. Scroll down to click on the subheadings, and check out the text of the ‘differential diagnosis,’ the ‘description’ and the ‘discussion’ sections for why it is placed in Homo. Yes, there is a lot of osteological jargon, but it’s not impossible to grasp the gist of it. The thing about the H. naledi site is that you have fossils from multiple individuals of a variety of ages, and that does generate population and even phylogenetic inferences. “Aside from these limited faunal materials, the Dinaledi collection is entirely composed of hominin skeletal and dental remains. The collection so far comprises 1550 fossil hominin specimens, this number includes 1413 bone specimens and 137 isolated dental specimens; an additional 53 teeth are present in mandibular or maxillary bone specimens. Aside from the fragmentary rodent teeth, all dental crowns (n = 179) are hominin, recovered both from surface collection and excavation. Likewise, aside from the few bird elements, all morphologically informative bone specimens are clearly hominin. In all cases where elements are repeated in the sample, they are morphologically homogeneous, with variation consistent with body size and sex differences within a single population. These remains represent a minimum of 15 hominin individuals, as indicated by the repetition and presence of deciduous and adult dental elements...” One thing I definitely did notice when I saw the photo of the H. naledi skull in the video of Berger was that the chin appeared to be more vertical than that of australopithecines, and in the paper I found this (bold emphasis mine): “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. A mental trigon on the chin is a human mandibular characteristic. Image for mental trigon: http:// https://arcjohn.files.wordpress.com/2016/11/45-e1478320807740.png I also noticed that the tips of the distal phalanges appeared rather wide which would indicate something about manual dexterity, so I checked against an A. afarensis hand that had one complete digit and thought that it, too, had a fairly broad apical tuft, but couldn’t really adequately compare. Here’s what the authors of the H. naledi paper say about it: “...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)...” Edited June 21, 2017 by Cricket
Guest DWA Posted June 21, 2017 Posted June 21, 2017 I definitely had not read that. I'd also consider it probable that those markers hadn't been documented yet by the time I read what I read. I'm always on the lookout for premature conclusions. As we know, this is one field full of them. But when you're right, you're right; and there appears justification to go Homo with this. Thanks Cricket!
Guest DWA Posted June 21, 2017 Posted June 21, 2017 Unfortunately, I am getting 'blank page' when I click the links. :-(
Guest DWA Posted June 21, 2017 Posted June 21, 2017 Guideposts to adult behavior are being laid out across the forum. ^^^Please comply. A dialogue between scientists is going on. Understand or move on.
WSA Posted June 21, 2017 Posted June 21, 2017 Ditto on the links for me too Cricket....blank pages. Still, you've given me something to chew on, and thank you very much. I don't think I have the chops to make cogent taxonomic arguments either way, but I like to try and grasp as much as possible on the topic.
Twist Posted June 21, 2017 Posted June 21, 2017 2 hours ago, WSA said: Ditto on the links for me too Cricket....blank pages. Still, you've given me something to chew on, and thank you very much. I don't think I have the chops to make cogent taxonomic arguments either way, but I like to try and grasp as much as possible on the topic. Im just trying to grasp some of the words in your post lol
Guest Cricket Posted June 22, 2017 Posted June 22, 2017 (edited) Sorry about the faulty links! I will post the paper again because it really is worth seeing. There are photos as well as the tables. https://elifesciences.org/articles/09560 and the image for the mental trigon: https://arcjohn.files.wordpress.com/2016/11/45-e1478320807740.png Yes, I realize this paper was not available when this thread was underway. I saw in another thread that someone had mentioned genetic engineering and muscle strength of BF, and it made me think of something I was told regarding the differences between human and African ape muscle tissue, so I'm going to look into that until I can make my next post....back in 24 hours! I think by the end of the week I will be 'off the leash' here Edited June 22, 2017 by Cricket
Guest DWA Posted June 23, 2017 Posted June 23, 2017 On 6/21/2017 at 10:20 PM, Cricket said: Sorry about the faulty links! I will post the paper again because it really is worth seeing. There are photos as well as the tables. https://elifesciences.org/articles/09560 and the image for the mental trigon: https://arcjohn.files.wordpress.com/2016/11/45-e1478320807740.png Yes, I realize this paper was not available when this thread was underway. I saw in another thread that someone had mentioned genetic engineering and muscle strength of BF, and it made me think of something I was told regarding the differences between human and African ape muscle tissue, so I'm going to look into that until I can make my next post....back in 24 hours! I think by the end of the week I will be 'off the leash' here Thanks for this, Cricket. Reading now.
Guest DWA Posted June 23, 2017 Posted June 23, 2017 (edited) "A date younger than 1 million years ago would demonstrate the coexistence of multiple Homo morphs in Africa, including this small-brained form, into the later periods of human evolution. The persistence of such a species with clear adaptations for manipulation and grip, alongside MP humans or perhaps even alongside modern humans, would challenge many assumptions about the development of the archaeological record in Africa." Might also make a number of other things highly questionable, including the unreasonable assumption, refuted virtually conclusively by solid evidence, that no way other hominids - as intelligent a type of animal as we have found - could have made it into the modern world with H. sapiens, when so many other "lesser" (highly questionable itself) species have. Edited June 23, 2017 by DWA
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