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Part 1 & PrologueJust Another Species of Big MammalPlease use this thread for discussing Part One and the Prologue of The Third Chimpanzee, which covers Chapters 1 and 2 and obviously the Prologue - pages 1 through 57.

In the Prologue, Diamond gives several ways in which humans differ from other apes (pg 7). What do you think are the most important differences? Has he left anything out that you would include?

I'm wondering how significant the statistics are in the Prologue. So we're very similar genetically to the other primates, but what is the difference between lets say a human and a dog? ...or a human and a frog? I imagine he gets to that later in the book, but right now, without anything to compare these stats to I am not appreciating their significance. I'm excited about this book though and hope we have plenty of participation.

While in the prologue Diamond states that the difference between both types of chimps and man is only 1.6%, a little further on (pgs 23 - 24) he compares the differences between monkeys and chimps (7.3%) and orangatans and chimps (3.6%) and between two species of very similar gibbons (2.2%). But like you I would like to know what the difference is between man and say, a mouse.

I may have a book that addresses this...I will see if I can find it. But did anyone do a search yet?Mr. P. Mr. P's place. I warned you!!!Mr. P's Bookshelf.I'm not saying it's usual for people to do those things but I(with the permission of God) have raised a dog from the dead and healed many people from all sorts of ailments. - AsanaThe one thing of which I am positive is that there is much of which to be negative - Mr. P.The pain in hell has two sides. The kind you can touch with your hand; the kind you can feel in your heart...Scorsese's "Mean Streets"I came to kick ass and chew Bubble Gum...and I am all out of Bubble Gum - They Live, Roddy Piper

The best way I've found to check this information is to run a search on comparative genomics.This from the U.S. National Human Genome Research Center fact sheet...www.genome.gov/11509542Has the field of comparative genomics yielded any results?The rapidly emerging field of comparative genomics has already yielded dramatic results. For example, a March 2000 study comparing the fruit fly genome with the human genome discovered that about 60 percent of genes are conserved between fly and human. Or, to put it simply, the two organisms appear to share a core set of genes.Researchers have found that two-thirds of human genes known to be involved in cancer have counterparts in the fruit fly. Even more surprisingly, when scientists inserted a human gene associated with early-onset Parkinson's disease into fruit flies, they displayed symptoms similar to those seen in humans with the disorder, raising the possibility the tiny insects could serve as a new model for testing therapies aimed at Parkinson's.More recently, a comparative genomic analysis of six species of yeast prompted scientists to significantly revise their initial catalog of yeast genes and to predict a new set of functional elements thought to play a role in regulating genome activity.And from genomics.energy.gov...www.ornl.gov/sci/techreso...pgen.shtmlThe often-quoted statement that we share over 98% of our genes with apes (chimpanzees, gorillas, and orangutans) actually should be put another way. That is, there is more than 95% to 98% similarity between related genes in humans and apes in general. (Just as in the mouse, quite a few genes probably are not common to humans and apes, and these may influence uniquely human or ape traits.) Similarities between mouse and human genes range from about 70% to 90%, with an average of 85% similarity but a lot of variation from gene to gene (e.g., some mouse and human gene products are almost identical, while others are nearly unrecognizable as close relatives). Some nucleotide changes are "neutral" and do not yield a significantly altered protein. Others, but probably only a relatively small percentage, would introduce changes that could substantially alter what the protein does.

Good...because I cound not find this info in my book!Mr. P. Mr. P's place. I warned you!!!Mr. P's Bookshelf.I'm not saying it's usual for people to do those things but I(with the permission of God) have raised a dog from the dead and healed many people from all sorts of ailments. - AsanaThe one thing of which I am positive is that there is much of which to be negative - Mr. P.The pain in hell has two sides. The kind you can touch with your hand; the kind you can feel in your heart...Scorsese's "Mean Streets"I came to kick ass and chew Bubble Gum...and I am all out of Bubble Gum - They Live, Roddy Piper

I have read a similar comparison between man and mouse, but it makes little sense. If there is a graduation between monkeys, chimps, and man, as Diamond writes, then there should be some greater difference between mice and men. The 85% average would mean that there is virtually no difference between monkeys and mice compared to men! I suspect that the more traits that are shared, the closer the DNA is likely to be. As mammals we share many more traits with apes that with mice. If the 85% similarity with mice were true, then it would mean that talking about DNA differences between any two species has no meaning.Diamond gives several examples of like species having similar DNA. Also, an article in Scientific American holds that there is less DNA difference between men and chimps than there is between dogs and foxes.

minority mandate: I have read a similar comparison between man and mouse, but it makes little sense. If there is a graduation between monkeys, chimps, and man, as Diamond writes, then there should be some greater difference between mice and men. The 85% average would mean that there is virtually no difference between monkeys and mice compared to men!Obviously, I'm no expert on comparative genomics, but given my limited understanding of the field, I'd say that there are two explanations. One is that a substantial portion of our DNA is probably devoted to very basic traits that are shared with just about all mammals, and laterally, by just about all known, complex life forms. So, yeah, it probably looks as though there's a huge amount of difference between a mouse and a man, but when you start adding up the things that they have in common -- skin, hearts, basic mammalian bone structure, heterosexual reproductive systems -- those are very complex elements and the very fact that they show up in both organisms probably accounts for a very large portion of their traits. Things like relative size and differences in shape may be much easier to code on a strand of DNA, which would explain why what we regard as major differences seem to make up only a very small percentage of the differences between the two species' DNA.In some part, that's a matter of perception. Do mice really have all that much in common with humans? It may seem like they don't, at least until you compare a human with a yeast.The other response is that, based on the articles I've linked to (specifically the second quote I provided), it looks as though the normative practice in comparative genomics has been to compare the DNA of shared genes -- eg. only comparing the genes that appear in both mice and humans, like the gene for, say, eyes -- and not making comparisons between the whole strand which would involve comparing genes that aren't shared by both -- say, for instance, genes for language acquisition. If that's the case, then it's easy to get a false impression of what's entailed by the posited similarities. What Diamond would actually be saying (if the text I quoted is applicable to The Third Chimpanzee) is that, for the traits we have in common, the genes of a human are more congruous to that of a human than to that of a mouse. In other words, the eye genes of a human are more similar to that of a chimp than that of a mouse -- which doesn't really imply much about how similar either the mouse or chimp genome is to that of the human, since humans may have genes that neither the mouse nor chimp have, and which are not being included in the comparison.Does that seem about right, based on everyone else's reading of the quoted text? Does anyone have any more information that might illuminate the subject?

Speaking to the point of mice as compared to humans...there are reasons that mice are used so much in research!!I believe the immune system in mice is very compatible with humans. I am saying this based on some nugget of info that is in my head and I cannot point to a source right now. But I do know that mice are good subjects for testing because of similarities.Mr. P. Mr. P's place. I warned you!!!Mr. P's Bookshelf.I'm not saying it's usual for people to do those things but I(with the permission of God) have raised a dog from the dead and healed many people from all sorts of ailments. - AsanaThe one thing of which I am positive is that there is much of which to be negative - Mr. P.The pain in hell has two sides. The kind you can touch with your hand; the kind you can feel in your heart...Scorsese's "Mean Streets"I came to kick ass and chew Bubble Gum...and I am all out of Bubble Gum - They Live, Roddy Piper