Joined: Feb. 2006
Hmm, I forgot there was more, back when Dave first started claiming he was never told how the African ape LCA was determined.
On June 7, I post a further reply:
|Quote (afdave @ June 12 2006,09:21)|
I will say to Incorygible that I am still waiting to hear why you think it is valid to say that gorillas diverged at 8mya and chimps and humans diverged at 5mya. I know you read it in a textbook, but my questions was, 'Why did the textbook think this is valid? What is the basis for saying this?'
That would be as easy as reading my answers and checking the references, wouldn't it? Lewin (1989; Chapter 3: Historical Views) gives a detailed history of scientific thought on human-ape relationships between the 1890s and the present. He covers fossil hominid discoveries, early protein comparisons, etc., and the dates they suggested for branching in the ape lineage. This includes the earlier and longer-held notion that chimps were closer to gorillas, and why this was overturned. If you want even more details on some of this evidence, I provided you with a good reference (Stein and Rowe 1989) and relevant chapters.
Now, rather than implying that I don't answer your questions because I'm not spoonfeeding you dozens of pages of text, how about answering the one big question I posed to you many times regarding why your "Creator God Hypothesis" doesn't match the data? This has nothing to do with what evoltuionary theory says and why. Whether you view the "1%" as important or not, it is clear that the differences between us and chimps are smaller than your proposed "microevolutionary" variation within the "ape kind" (chimps and gorillas, plus we haven't even touched orangutans, which you would group in the ape kind, but have been known to be a significantly different outgroup since the 1920s). Why do your Creator's code and the fossils of His Flood so strongly suggest to us that humans are just another ape, contrary to His book?
And then, after he persisted, on June 21, I painstakingly typed out a key chunk of the book I was using in an effort to finally put this "how did you get the 8 my" lie to rest:
|Quote (afdave @ June 21 2006,11:21)|
No conspiracy. Just a rather arrogant consensus that the Bible is a fairy tale and anything that sound 'Biblical" or 'religious' is pretty much ignored with no investigation.
You're wrong, Dave. You're not the first to use the Bible as a source of hypotheses. It's been used in exactly that fashion for two thousand years. Caused no small degree of consternation when those hypotheses didn't pan out. Where the Bible matches the evidence (e.g., history), it remains a source of information. Where it doesn't (e.g., science), there's not much left to investigate. And "arrogance" is an interesting characterization by somebody with such lofty opinion of his own faith and knowledge that he's willing to discount practically every biologist, physicist, and geologist on the planet.
You keep repeating this, but why? My question is why? Why the millions of years? Do you have some math formula or something? Or is it just a regression of 'this book quotes this other book which quotes this other book which quotes this other book' etc. etc. all the way back to Darwin or somebody? Who put it in print first in modern times that apes and humans had a common ancestor several mya? And why did they say this? That's what I am trying to get you to tell me.
Why, Dave? Why? I repeat it because it illustrates the difference between your worldview and mine, and the projections you make. You are so confident in revelation without method, assertion without evidence, and knowledge without information that you assume that's where my "belief" comes from. You really think we can trace scientific understanding of life and the universe back to the pronouncements of some prophet on a mountain top, analogous to the source of your knowledge. Yes, Dave, books quote other books. They summarize them, answering the "why" on one level. If you want more, you go to those other books. But if you really think all of evolutionary theory (or even just the phylogeny of the great apes) reduces to "who put it in print first", you just don't get it.
But to answer your simple (and rather irrelevant) question: "Who put in print first in modern times that apes and humans had a common ancestor several mya? And why did they say this?"
Once again, I will refer you to that Lewin book you said you read, specifically Chapter 3 "Historical Views", which I referenced for you:
"During the past century, the issue of our relatedness to the apes has gone full cycle. From the time of Darwin, Huxley and Haeckel until soon after the turn of the centruy, humans' closeses relatives were regardes as being the African apes, the chimpanzee and gorilla, with the Asian great ape, the orangutan, being considered to be somewhat separate. Then, from the 1920s until the 1960s, humans were distanced from the great apes, which were said to be an evolutionarily closely-knit group. Since the 1960s, however, conventional wisdom has returned to its Darwinian cast."
[skip 2 pages of description regarding the players and positions in the first half of the 20th century]
"During the 1950s and 1960s, fossil evidence of early apes accumulated at a significant rate, and it seemed to show that these creatures were not simply early versions of modern apes, as had been tacitly assumed. This meant that those authorities who accpeted an evolutionary link between humans and apes, but did not accept a close human/African ape link, did not now have to go way back in the history of the group to 'avoid' the specialization of the modern species. At the same time, those who insisted that the similarities between African apes and humans were the result of common heritage, not parallel evolution, were forced to argue for a very recent origin of the human line. Prominent among proponents of this latter argument was Sherwood Washburn, of the University of California, berkeley.
"One of the fossil discoveries of the 1960s -- in fact, a rediscovery -- that appeared to confirm the notion of parallel evolution to explain human/African ape similarities was made by Elwyn Simons, then of Yale University. Ramapithecus was the fossil specimen, an apelike creature that lived in Eurasia about 15 million years ago and appeared to share many anatomical features (in the teeth and jaws) with hominids. Simons, later supported closely by David Pilbeam, proposed Ramapithecus as the beginning of the hominid line, thus excluding a human/African ape connection.
"Arguments about the relatedness between humans and African apes took place against a rethinking about the relatedness among the apes themselves. In 1927, G.E. Pilgrim had suggested that the great apes be treated as a natural group, with humans evolutionarily more distant. The idea eventually became popular, and was the accepted wisdom until molecular biological evidence undermined it in 1963, the work of Morris Goodman at Wayne State University. Goodman's molecular biology on blood proteins indicated that humans and the African apes formed a natural group, with the orangutan more distant.
"Thus, the Darwin/Huxley/Haeckel position was reinstated, with first Gregory and then Washburn its champions. Subsequent molecular biological -- and fossil -- evidence seems to confrim Washburn's original suggestion that the origin of the human line is indeed recent, lying between 5 and 10 million years ago. Ramapithecus was no longer regarded as the first hominid, but simply one of many early apes."
[skip a few pages discussion of more recent fossil hominids, too use, etc., not to mention historical phylogenetic trees showing the perceived evolutionary relationships between men and apes, including a 1927 version with "negroes" and "negroids" divering not long after Neanderthal]
"During the past decade, not only has there been an appreication of a spectrum of hominid adaptations -- which includes the notion simply of a bipedal ape -- but the lineage that eventually led to Homo sapiens has come to be perceived as much less human. Gone is the notion of a scaled-down version of a modern hunter-gatherer way of life. In its place has appeared a rather unusual African ape adopting some novel, un-apelike modes of subsistence.
"Hominid origins are thereforenow completely divorced from any notion of human origins. Questions about the beginning of the hominid lineage are now firmly within the territory of behavioral ecology, and do not draw upon those qualities that we might perceive as separating us from the rest of animate nature. [HINT: These are "qualities" like writing, SATs, and table manners, Dave] Questions of human origins have now to be posed within the context of primate biology."
[Exit the chapter on Historical Perspectives demonstrating that there was NO pronouncement by any patriarchal authority, but that thought developed, changed, and changed back more than once as the evidence appeared. Turn to Chapter 9 on Molecular Perspectives, which describes dated fossil finds and DNA data.]
"The shape of the hominoid tree according to the molecular evidence available in the early 1980s was therefore as follows: gibbons split away first, about 20 million years ago; orangutans next, about 15 million years ago; leaving humans, chimpanzees and gorillas in an unresolved three-way split, close to 5 million years ago. A three-way split of a lineage is biologically unlikely, and in this case it meant that the timing of the different divergences was so tightly bunched that none of the techniques was able to prise it apart with any confidence.
"Meanwhile, most morphologists had since the 1960s accepted the notion of a human/African ape clade, with an African ape clade existing within that. The expectation among molecular biologists, therefore, was that their data would confirm this pattern. showing that the common ancestor of humans and the African apes diverged to produce the human lineage on the one hand and an African ape lineage on the other, which then subsequently split to produce gorillas and chimpanzees.
[WOW, eh Dave? In the early 1980s, they were still expecting chimps to be closer to gorillas. Do you think a certain amount of your "I wouldn't invite a chimp to dinner" thinking led to that expectation? Kinda different then your idea that we have an innate, arrogant urge to convince everyone he's a monkey, eh?]
"It was therefore something of a surprise when, in 1984, Charles Sibley and Jon Ahlquist, then of Yale University, published data on DNA-DNA hybridization that strongly implied that chimpanzees are more closely related to humans than they are to gorillas. Gorillas evolved from the human/African ape common ancestor between 8 and 10 million years ago, they concluded, leaving humans and chimpanzees briefly sharing a common ancestory of their own, and splitting at between 6.3 and 7.7 million years ago."
Then we have a table, titled "Converging Evidence":
Time Ape/human divergence date (millions of years)
1980s 5-8 5-8
1970s 15 5
1960s 30 5
Then we have a tree, with Time -- Millions of years, illustrating:
So, your question of how I arrived at my 1985 prediction, way back when? Simple. By 1985, molecular and fossil data had converged on a split between humans and other apes (i.e., chimps) at 5 million years ago (the number I used). The gorilla estimate from 1989 was 7.7-11.0, but this included some of the new DNA techniques that we were supposed to be "predicting". So I went with a ballpark around 8 mya, which was the upper end of the 5-8 mya range of the "convergence" between fossils and "molecules", nicely "between 5 and 15, but closer to 5" from early 1980s fossil discoveries, the lower end of the 8-10 mya range from the first 1984 foray into DNA technology (which I would have been rightly skeptical of, but intrigued, in 1985), and closest to the 5 mya for the "three-way-split" from established molecular studies.
That's where I got my dates for in my silly (but fun) little hypothetical exercise, Dave. Don't you wish you could give an answer like that for your own arguments? Something other than "it's obvious" or "imagine you went to dinner/bed/school with a chimp"? Ever?
If this doesn't elevate Dave's lie from egregious to unequivocally sinful, I don't know what would. You are an evil liar, Dave.