Hello,

I recently stumbled upon this post written by Jonathan M: http://www.evolutionnews.org/2011/10/wikipedia_and_common_descent_p051681.html

This has been the only creationist article that I found which dealt with this subject in more depth. I haven't seen any response to it so far and, as I'm not an expert on biology, didn't know what to think of it.

Is the criticism in the link above valid?

Thanks

Without wishing to write a full scale article, no, of course it's not valid criticism - it's a lame attempt at shunting the findings of science off into a corner while espousing an entirely unscientific claim as if it has at least equal weight, if not greater.

If there are particular details you want information on, can you be a little more specific: a full rebuttal would take more time than I am prepared to give this guy.

I just Skimmed the link and found the following quote puzzling:-

For one thing, there are, in fact, plausible alternative explanations for this observation. For example, envision a scenario where our genus Homo, originally possessing 48 chromosomes, underwent a chromosomal fusion event within its own independent lineage.

How is that an alternative explanation? To my understanding this is exactly what happened - the Homo lineage used to have 48 chromosomes, as do all other members of Hominidae, and did undergo a chromosomal fusion event within its own independent lineage.
The only questionable thing is when in the history of the Homo lineage did this occur, before or after the genus Homo evolved.
Even so one still has to question why all members of Hominidae had 48 chromosomes up to the point at which the Homo lineage underwent a chromosomal fusion?
I guess the writer of the article simply does not understand this as a piece of evidence for evolution at all.

Also the assertion that

But then we are only coming back to the argument from similarity which, as I have already argued, supports common descent no more than it suggests common design.

Ignores the fact that the common design hypothesis is un-falsifiable, as whatever pattern was found one could claim that it was the will of the designer to make it so, and therefore it is of no scientific value as an explanation.
All one needs to do is ask someone who makes this claim - what are the constraints that would necessitate the designer to design it this way and not another?
The constraints in common descent are obvious - it must have been inherited.

ABE: welcome chcksr

Thanks you for your welcoming halucigenia

@Spearthrower:
I'm interested about this part: "Secondly, some of the arguments for supposing that chromosome 2 did indeed arise from a fusion event have been significantly weakened in recent years. One very interesting peer-reviewed paper, appearing in the journal Cytogenetic and Genome Research in 2009, by Farre, Ponsa and Bosch, reported...." .
He closes by saying "Thus, the take-home message is this: To make much of the 2q13 interstitial telomeric sequence and portray it as typical of what is observed in chimp and human genomes may be considered careful cherry-picking of data."

What I understand (from what he is saying) is that scientists report evidence for fusion exists based only on the presence of the 2q13 site while ignoring others because they don't fit the theory.
What can be said about this?

I will see if I can get that article, because I think we're all well aware of Creationist mendacity with respect to commenting on papers, but regardless of that - I like the way he's cherrypicking articles that purportedly lend support to his claim, while rejecting the others, then claiming that the scientists are cherrypicking data.

This appears to be the paper if anyone's got pubmed access?

http://www.ncbi.nlm.nih.gov/pubmed/1942 ... t=Abstract

Abstract

Although their function has not yet been clearly elucidated, interstitial telomeric sequences (ITSs) have been cytogenetically associated with chromosomal reorganizations, fragile sites, and recombination hotspots. In this paper, we show that ITSs are not located at the exact evolutionary breakpoints of the inversions between human and chimpanzee and between human and rhesus macaque chromosomes. We proved that ITSs are not signs of repair in the breakpoints of the chromosome reorganizations analyzed. We found ITSs in the region (0.7-2.7 Mb) flanking one of the two breakpoints in all the inversions assessed. The presence of ITSs in those locations is not by chance. They are short (up to 7.83 repeats) and almost perfect (82.5-97.1% matches). The ITSs are conserved in the species compared, showing that they were present before the reorganizations occurred.

Looking for other sources.

Of course there's also the dysfunctional second centromeric site and the correspondence of the DNA sequences.

http://en.wikipedia.org/wiki/Chromosome_2_(human)

Bert

The "independent lineage" bit means a lineage that was never connected to a non-human one; if the human and chimpanzee lineages were created separately (independently) with the same number of chromosomes, then the fact that one of them changed and became different from the other is no big deal.

What this means they're leaving out when they bring up the "argument from similarity" is the chronological component: not just that different organisms resemble each other in certain ways, but that their similarities were greater in the past.

halucigenia wrote:I just Skimmed the link and found the following quote puzzling:-

For one thing, there are, in fact, plausible alternative explanations for this observation. For example, envision a scenario where our genus Homo, originally possessing 48 chromosomes, underwent a chromosomal fusion event within its own independent lineage.

How is that an alternative explanation? To my understanding this is exactly what happened - the Homo lineage used to have 48 chromosomes, as do all other members of Hominidae, and did undergo a chromosomal fusion event within its own independent lineage.

I think his intent is to suggest that ancestors of human and those of the other ape species could have been completely unrelated, but just happened to coincidentally have the same number of chromosomes (48) as one another.
Of course this completely ignores the startling similarity of those chromosomes, that for instance the chromosomes of humans and chimpanzees match almost perfectly, except for the humans fused chromosome - which matches almost perfectly with the two other chromosome pairs of chimpanzees. Meaning that humans don't simply happen to have 23 pairs with one a fusion of two, and chimpanzees having 24 pairs, but humans would have 24 chromosomes if the fused one was split which are practically identical to those of chimpanzees!

Only having skimmed it myself, this problem seems to persist throughout; focusing on one piece of evidence, and claiming that it could be otherwise, but failing to address the combined strength of all of those pieces of evidence when looked at as a whole!

Yes, the purpose of the article is to split up the different lines of evidence one by one and then pretend no single one is convincing, thus ignoring it all in the end.

You can always come back and ask isn't it kind of strange that we should posess the exact same chromosomes as all the other great apes, complete with the same genes located on the same chromosomes, and then our chromosome 2 just happens by chance to be fused in the exact location that would hint it derives from two pairs of chromosomes in a common ancestor we share with the other great apes? Oh no, that's just chance I guess. Same goes for the phylogenetic sequence homologies that implies common descend, that's just chance. Same goes for comparative anatomy and developmental biology, that's just chance again. Same goes for the fossil record, pure coincidence. Etc. etc.

Rumraket wrote:Yes, the purpose of the article is to split up the different lines of evidence one by one and then pretend no single one is convincing, thus ignoring it all in the end.

You can always come back and ask isn't it kind of strange that we should posess the exact same chromosomes as all the other great apes, complete with the same genes located on the same chromosomes, and then our chromosome 2 just happens by chance to be fused in the exact location that would hint it derives from two pairs of chromosomes in a common ancestor we share with the other great apes? Oh no, that's just chance I guess. Same goes for the phylogenetic sequence homologies that implies common descend, that's just chance. Same goes for comparative anatomy and developmental biology, that's just chance again. Same goes for the fossil record, pure coincidence. Etc. etc.

Attempting to get into the head of a Creationist (yuck) I presume that the claim is not "chance" but "common design". The genetic similarities being due to common elements in the design of the various species. On that basis they should claim that Chromosome 2 is not a "fusion event" but a "design revision".

And of course, one inconvenient fact that creationists won't touch with a barge pole, is the fact that Linnaeus, sixty two years before Darwin was born, alighted upon the idea that humans and chimpanzees were related, on the basis of comparative anatomy alone, and even wanted to place humans and chimpanzees in the same taxonomic Genus. The reason he didn't? Oh, that's right, interfering religious busybodies in the church trying to tell scientists what their science should say.

Calilasseia wrote:And of course, one inconvenient fact that creationists won't touch with a barge pole, is the fact that Linnaeus, sixty two years before Darwin was born, alighted upon the idea that humans and chimpanzees were related, on the basis of comparative anatomy alone, and even wanted to place humans and chimpanzees in the same taxonomic Genus. The reason he didn't? Oh, that's right, interfering religious busybodies in the church trying to tell scientists what their science should say.

So why is it that the Homo and Pan genera are used by scientists today to define us and chimps?

chcksr wrote:Hello,

I recently stumbled upon this post written by Jonathan M: http://www.evolutionnews.org/2011/10/wikipedia_and_common_descent_p051681.html

This has been the only creationist article that I found which dealt with this subject in more depth. I haven't seen any response to it so far and, as I'm not an expert on biology, didn't know what to think of it.

Is the criticism in the link above valid?

Thanks

I have long maintained that the fusion event happened in a human ancestor who was himself a human. There is no need to hark back to a more distant hypothetical ancestor.

Atheistoclast wrote:

Calilasseia wrote:And of course, one inconvenient fact that creationists won't touch with a barge pole, is the fact that Linnaeus, sixty two years before Darwin was born, alighted upon the idea that humans and chimpanzees were related, on the basis of comparative anatomy alone, and even wanted to place humans and chimpanzees in the same taxonomic Genus. The reason he didn't? Oh, that's right, interfering religious busybodies in the church trying to tell scientists what their science should say.

So why is it that the Homo and Pan genera are used by scientists today?

Because they stuck. You are aware taxonomy is merely for classification and assistance for identifying an organism right? By all means the concepts of Genus and Species are barely existent in the natural world.

Atheistoclast wrote:

chcksr wrote:Hello,

I recently stumbled upon this post written by Jonathan M: http://www.evolutionnews.org/2011/10/wikipedia_and_common_descent_p051681.html

This has been the only creationist article that I found which dealt with this subject in more depth. I haven't seen any response to it so far and, as I'm not an expert on biology, didn't know what to think of it.

Is the criticism in the link above valid?

Thanks

I have long maintained that the fusion event happened in a human ancestor who was himself a human. There is no need to hark back to a more distant hypothetical ancestor.

Maintained with what empirical evidence?

Atheistoclast wrote:I have long maintained that the fusion event happened in a human ancestor who was himself a human. There is no need to hark back to a more distant hypothetical ancestor.

So the rest is co-incidence?

John