Posted: Feb 25, 2014 7:32 pm
by Calilasseia
questioner121 wrote:
Skate wrote:Damn, Calilasseia! Nice post.

Questioner,

Is it correct that your argument sums up to amount to something akin to "you weren't there, so you can't know?" Others have said this, but I'd like to confirm that this is the case.

If so, I'd like to ask you how you think the Hawaiian Islands were formed.


Obviously "you weren't there, so you can't know?" applies.


No it doesn't, for the reason I've repeatedly schooled you on, namely, that physical processes leave behind them physical evidence of their having taken place. Your continued and duplicitous attempts to deny this basic fact, are akin to trying to tell us all that coins found on archaeological digs aren't evidence of the civilisations producing them.

questioner121 wrote:The point I'm trying to get across, with huge difficulties, is that the evidence supporting common ancestry is severely lacking data.


Bullshit. There are several thousand papers extant in the molecular phylogeny literature alone, all containing detailed descriptions of the evidence they examined. Indeed, as I've repeatedly stated here, if common ancestry hadn'tt occurred, then molecular phlogeny as a discipline would not exist, because it would be impossible to amass the data. The mere fact that the data can be amassed on its own tells us something important here, and that's before we factor in the manner in which other bodies of data are enormously consilient with the molecular phylogeny findings.

questioner121 wrote:The abundance of data that is used to support common ancestry is based off observations from closely related species.


You obviously haven't read anything on the subject, have you? Because if you had, you would know that molecular phylogeny includes studies covering the entire biosphere.

Plus, your admission above that some species are closely related, itself leads to the question of what form that relationship takes. Which is the question the scientists have been addressing, in case you hadn't worked this out.

questioner121 wrote:This is then being combined with other sets of data with observations from closely related species to "confirm" common ancestry.


Oh wait, Douglas Theobald's test of common ancestry was based upon an entirely different methodology. Theobald's test consisted of constructing rival models, then testing to see how well those different models matched the data. When he did this, he found that universal common ancestry provided a massively better fit to the data than rival models. In his paper, he demonstrated that universal common ancestry was a whopping 102,860 times more probable than rival, multiple-ancestor models. His test covered all three domains of life, Archaea, Eubacteria and Eukarya.

questioner121 wrote:The missing data is for one species right through to a very different species, such as from primate to human, reptile to bird, etc is simply not there.


Lie. How many fossils do we have to bring here to establish this?

questioner121 wrote:Citing extinctions and whatever else might have caused the common ancestor to be no longer around or missing chains from ring species is just not relevant.


Oh wait, the common ancestor is usually no longer around, because it's given rise to new descendants. However, one interesting exception to the rule is provided by the Cichlid fishes of Lake Victoria, which, upon the basis of molecular phylogeny, were determined to have arisen from an ancestral population of Haplochromis gracilior from nearby Lake Kivu. The fun part being, of course, that Haplochromis gracilior is still alive and well in Lake Kivu. The relevant paper is this one:

Origin Of The Superflock Of Cichlid Fishes From Lake Victoria, East Africa by Erik Verheyen, Walter Salzburger, Jos Snoeks and Axel Meyer, Science, 300: 325-329 (11 April 2003) [Full paper downloadable from here]

Verheyen et al, 2003 wrote:Lake Victoria harbors a unique species-rich flock of more than 500 endemic haplochromine cichlid fishes. The origin, age, and mechanism of diversification of this extraordinary radiation are still debated. Geological evidence suggests that the lake dried out completely about 14,700 years ago. On the basis of phylogenetic analyses of almost 300 DNA sequences of the mitochondrial control region of East African cichlids, we find that the Lake Victoria cichlid flock is derived from the geologically older Lake Kivu. We suggest that the two seeding lineages may have already been lake-adapted when they colonized Lake Victoria. A haplotype analysis further shows that the most recent desiccation of Lake Victoria did not lead to a complete extinction of its endemic cichlid fauna and that the major lineage diversification took place about 100,000 years ago.


Further on in that paper, we have:

Verheyen et al, 2003 wrote:Lake Kivu is located in the African Rift Valley and is completely isolated from the much younger LV (16). The formation of the Virunga Volcanoes about 14,000 to 11,000 years ago (17) or 25,000 to 20,000 years ago (16) interrupted the previous connection of proto–lake Kivu to the northern Rift lakes. Lake Kivu harbors 26 fish species, of which 15 are endemic haplochromines (18). Though presently connected to the Tanganyika system via the Rusizi, it is part of the East Coast ichthyogeographical region that includes Lakes Victoria, Edward, and George (18).

Here, we adopt a comprehensive phylogeographic approach to address the question of the origin of the haplochromine superflock, using sequence data published by Nagl et al. (7) and new sequences obtained in this study. These include: mitochondrial control region sequences (847 base pairs long) from East African haplochromine cichlids of lakes Victoria, Edward, George, Albert, representative East African rivers, and new sequences from 133 LK haplochromines representing 14 out of its 15 known endemic haplochromines, as well as sequences from fishes from small lakes in Uganda and Burundi. Sources of sequences and Genbank accession numbers are given in table S1.

In agreement with earlier studies (6, 7), our phylogenetic analyses (19) show that the Lake Victoria, Edward, George, and Albert haplochromines form a monophyletic superflock that includes two specimens (7) originating from Tanzanian rivers close to Lake Rukwa (Figs. 1 and 2A). Except for three specimens of all the assayed haplochromines from LK, all Kivu cichlids sampled belong to this superflock (Fig. 2). These three specimens have been identified as Haplochromis gracilior (Fig. 2C), an endemic LK species that is clearly phylogenetically distinct from the superflock haplochromines (by 30 to 42 mutations), and also occupies a pivotal position because it does not belong to the superflock, but appears to be its most recent sister species.

Our haplotype network approach (19, 20)—permitting a fine-grained reconstruction of the evolutionary histories of these young lacustrine faunas—shows that the cichlids from LK are crucial for the evolutionary history of the LV superflock. The haplotypes of H. gracilior have a state “A” in the diagnostic site 630 (Fig. 3C) and are therefore connected to the network through the central Rift Valley haplotype (25 in Fig. 3C). The haplotype network demonstrates the extensive sampling, because almost all possible haplotypes are represented (Fig. 3C). Four additional observations support the crucial role of LK haplochromines in the evolution of all the haplochromines of eastern Africa: (i) the haplotypes of fishes from other lakes are connected by, and therefore derived from, LK haplotypes; (ii) the LK fish are relatively more diverse, although LK currently contains only 15 species as compared to more than 500 in LV; we detected 41 haplotypes in the faunas from both lakes; (iii) even excluding H. gracilior, LK haplotypes show an average pairwise distance of 0.6% as compared to 0.5% for LV; (iv) a central haplotype (25 in Fig. 3C) is found in some species from all large lakes, but more than 50% of the fishes with this haplotype are LK endemics.


Here's the phylogenetic family tree Verheyen et al constructed from the genetic data:



Lake Victoria Cichlid Phylogeny.jpg


Lake Victoria Cichlid Phylogeny.jpg (855.92 KiB) Viewed 822 times





questioner121 wrote:We know species die off and there can be numerous reasons. There needs to be actual evidence of one species going to a completely different one before it can be confirmed.


How many papers from the speciation literature do we have to bring here? Oh wait, speciation has been observed on numerous occasions, both in the wild and in the laboratory. Indeed, Hackenslash has just reminded me of a particularly interesting example, involving Heliconius butterflies, in which the genetic data was used to determine the existence of a speciation event in the wild, which was then reproduced in the laboratory.

Game over methinks.

questioner121 wrote:Otherwise inference from the current data is ridiculous to confirm common ancestry beyond reasonable doubt especially given the understanding of nature we have which is hugely complex and in many situations quite unpredictable.


Bullshit. See above.

questioner121 wrote:
Calilasseia wrote:
Oh wait, I've already told you to look up fertillin genes. Which, wait for it, acquire changes over time leading to those incompatibilities.


Is the fertillin genes the deciding factor in whether one population can interbreed with another? If so then it should be possible to modify it so that reptiles and birds can interbreed and for that matter most animals.


Oh for fuck's sake, the biological ignorance in your posts is truly irritating to behold.

First of all, whilst fertillin genes play a significant role in species determination, because they play a large role in determining whether or not a sperm can fertilise an egg, they are not the sole determinants of speciation events. Other genes also contribute.

Second, once a lineage has had sufficient time to acquire a large number of differences within its members, the sort of Frankenstein chimaera experiment you hilariously offer up above is a non-starter. Oh wait, that large number of differences, in the case of birds and modern reptiles, includes a large number of significant anatomical features as well. Not to mention acquisition of large variation in chromosome count.

Once again, go and pick up some biology textbooks, and acquire some elementary knowledge, instead of posting shit like your above fantastic Frankenstein scenario.