How could we define homolog so that the genes in question have no chimp homologs? I’d have to reach way back to find a better example of your sheer bloodymindedness.
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The term “de novo” is really a misnomer in this context. There are indeed regions of the genome that develop the capability of being transcribed, and even fully expressed into polypeptides. However, these sequences did not simply appear out of the blue, but developed from sequences already present in the genome. If I understand how the BLAST tool works, it doesn’t do a great job of matching query sequence to un-annotated sequence (sequences not identified as translated or transcribed). So the lack of identified homologs for “de novo” genes does not tell the whole story. @T_aquaticus, please correct me if I’m wrong here.
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Those 56 sequences had an average length of 159bp, for a total of less than 9kb of sequence.
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If you are going to be serious about this “no evolution above the level of Genus”, I suggest you buckle down and actually investigate that claim in the most narrow part of the evolutionary path that actually matters: the Order Primates.
You know as well as I do that even if we proved evolution above the Genus level in fish, or reptiles, that Creationists (maybe even you?) would simply double-down and say: yeah, but what about Primates?!
So… let’s just go right to that group!
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There are 448 living species of Primates … and because they are living, they can have their genetic profiles compared. And we can drill down really deep, and really granular… to look at what the evidence actually shows.
So… Bill Cole… where in the Orders, Families and Genus’ of the Primates do you see a discontinuity worth discussing? Obviously, you can’t point to Homo sapiens as the discontinuity … because that’s the point that is trying to be proven ultimately. We need to examine some part of this group that doesn’t require references to humans.
It’s your circus… your monkeys (hey… did you see what I did there?)…
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what about the genes for a language?
What genetic evidence would convince you of a problem with the hypothesis that chimps and humans share a common ancestor solely from natural reproductive processes?
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Discontinuities in the nested hierarchy, obviously.
I’m only a novice when it comes to the ins and outs of BLAST, so don’t take my comments as gospel.
BLAST doesn’t use annotation, so that isn’t a problem. It simply searches for matches between sequence using user defined settings. You can change the specificity for a match, including penalties for gaps and the like.
I wouldn’t be surprised at all if there are short segments (~1000 base pairs) in any genome that has no detectable homology to other genomes since there are all sorts of mechanisms that can produce them. Funky recombination events and DNA breaks can produce all sorts of sequences. What is really strange is that ID/creationists think the emergence of new functional sequence is a problem for evolution when this is something the theory says should happen.
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Finding exact copies of genes from very distant species that are not found in other ape genomes or in the rest of the mammal tree. For example, there are mice that carry an exact copy of a jellyfish gene for green fluorescent protein, and that was produced by design.
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Why don’t you find those human genes and compare them to the chimp genome?
about 1\3 of gorila genes contradict the primate phylogeny. evolution is now wrong? im sure not.
Evolution predicts the relative amount of incomplete lineage sorting that we should see, so no, it isn’t wrong. As we move to more distant branches the amount of ILS goes down, as we would expect with evolution.
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but we do find such cases in nature. and scientists solving it by convergent loss or convergent evolution or LGT.
What distinguishes a chimp from a human?
Not DNA, really. Not proteins – many proteins in you, and in a chimp, are amino-acid-by-amino-acid identical.
Jonathan Marks (2009, p. 246; emphasis added) understands:
It is not that difficult to tell a human from an ape, after all. The human is the one walking, talking, sweating, praying, building, reading, trading, crying, dancing, writing, cooking, joking, working, decorating, shaving, driving a car, or playing football. Quite literally, from the top of our head (where the hair is continually growing, unlike gorillas) to the tips of our toes (the stoutest of which is non-opposable), one can tell the human part from the ape part quite readily if one knows what to look for. Our eye-whites, small canine teeth, evaporative heat loss, short arms and long legs, breasts, knees, and of course, our cognitive communication abilities and the productive anatomies of our tongue and throat are all dead giveaways. However, they are not readily apparent in a genetic comparison.
Until evolutionary biology can connect these anatomical, physiological, and behavioral differences – no chimps are reading this right now – to their causative DNA differences in the chimp and human genomes, respectively, all the DNA comparisons in the world won’t really bear on the unsolved evolutionary puzzle.
Pace Jared Diamond, we are not the “third chimpanzee.”
You can access the Marks 2009 paper here:
[PDF] What is the viewpoint of hemoglobin, and does it matter? | Semantic Scholar
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Name one gene shared by just humans and jellyfish that is not shared by any other species group.
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Then how do you explain the phenotypic differences between chimps and humans? What is causing it?
A Nobel Prize awaits the biologist who answers that question.
Then it seems that you only have an argument from ignorance. You are only citing our ignorance of which specific DNA differences are causing specific phenotypic differences.
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i can show you something similar like this one:
the magic word is LGT. evolution is false now?
Look in a mirror. You are the one who claims that DNA similarities and differences are the locus of explanatory significance.
Very early in our friendship, I asked Josh Swamidass to show me where, in the chimp and human genomes (respectively), the loci were that explained why humans have white sclera, and chimp, colored sclera. A very minor phenotypic difference; we’re not talking about the origins of language.
Josh didn’t know then (a few years ago), and no one knows today.
So color me underwhelmed about DNA comparisons.