addressalign-toparrow-leftarrow-rightbackbellblockcalendarcameraccwchatcheckchevron-downchevron-leftchevron-rightchevron-small-downchevron-small-leftchevron-small-rightchevron-small-upchevron-upcircle-with-checkcircle-with-crosscircle-with-pluscrossdots-three-verticaleditemptyheartexporteye-with-lineeyefacebookfolderfullheartglobegmailgoogleimageimagesinstagramlinklocation-pinmagnifying-glassmailminusmoremuplabelShape 3 + Rectangle 1outlookpersonplusprice-ribbonImported LayersImported LayersImported Layersshieldstartickettrashtriangle-downtriangle-uptwitteruseryahoo

Re: [philosophy-31] Darwin Misunderstood -Scientific American Magazine

From: Heide
Sent on: Monday, February 23, 2009 12:55 PM
Great points made by everyone, but I think it's time to move this to the "discussion board" on the APDG website, so ALL the members can participate in the discussion and not be bombarded (which is a possiblitiy in the future...just thinking ahead folks) by emails.
 
Thanks to all who have thus far shown interest in the topic and we look forward to other inputs and discussions on the "dissussion board".
Heidi P.


From: Jon Roland <[address removed]>
To: [address removed]
Sent: Monday, February 23,[masked]:02:35 AM
Subject: Re: [philosophy-31] Darwin Misunderstood -Scientific American Magazine

The anniversary of Darwin gives occasion to discuss evolution and genetic processes, but it should be kept in mind that those genetic processes were unknown to Darwin, and progress in the field makes evolution a more complex process than most people appreciate. Here are a few of those complications:

1. Mutation is not just a matter of copying errors or radiation damage. Chromosomes can get split, stitched together, doubled, or lost altogether.
2. Mitochondria also have genes that propagate only along the female line, and randomly mutate.
3. The cytoplasm plays a role in genetics that is not yet well understood, but all the action is not in the chromosomes. You don't get a copy of a dinosaur just with the dinosaur DNA in the chromosomes. You also need at least closely related  cytoplasm and mitochondrial DNA.
4. DNA can pass between cells of different species through other than meiosis. It can be injected by infective microorganisms and viruses, among other means.
5. The expression of genes, even if not suppressed by other genes or processes, is subject to random error. Our chromosomes contain less than 10^-11 of the information needed to specify the microstructure of adult organisms. The variations are neither the result of nature (genes) nor nurture (environment influences), but of chance. Identical twins have the same DNA when born that make it likely (but not certain) they will have fingerprints, but not identical fingerprints. Genes guide what is is largely a self-organizing, chaotic process.
6. Our DNA continues to change as we grow, so that by adulthood different cells have slightly different DNA, and identical twins no longer have perfectly identical DNA.
7. Besides the selective pressure from the natural environment, competitors, and food or prey, or from sexual selection, there is also social selection of individuals advantageous to the group, which seems likely to be important for primates in general and humans in particular.
8. Genetic change can involve both replacement of genes and the overlaying of their expression, which is how we retain remnants of ancestors, or the recapitulation of evolution in embryos. Each gene and more, the expression of it, involves an investment of energy and risk, that to be sustained requires a payoff in reproductive success, lacking which it will tend to disappear, slowly if it has little impact on reproductive success, and faster if the negative effect is large.
9. As has been pointed out, cooperation can be selected for as much as competition. That is how social species occur, and most mammals and birds are social to some degree. As Wilson and others have pointed out, adults are genes' way of producing more genes of the same line, and it makes sense for the group for individuals to sacrifice their own reproductive success to protect the progeny of their close relatives.
10. What we call morality and constitutional government is largely an expression of what is rational for social groups whose individuals have certain capabilities. It is not arbitrary or accidental, but an optimal strategy that we can expect will reappear anywhere in the Universe that a social species roughly like ours does. The details of this conjecture remain to be supported  by sufficient evidence and analysis, but I am confident this will be achieved in due course.

-- Jon

----------------------------------------------------------------
Jon Roland                                          512/[masked]
2900 W Anderson Ln C[masked], Austin, TX 78757 www.jonroland.org
----------------------------------------------------------------




--
Please Note: If you hit "REPLY", your message will be sent to everyone on this mailing list ([address removed])
http://philosophy.meetup.com/31/
This message was sent by Jon Roland ([address removed]) from Austin Philosophy Discussion Group (APDG).
To learn more about Jon Roland, visit his/her member profile: http://philosophy.meetup.com/31/members/4784383/
To unsubscribe or to update your mailing list settings, click here: http://www.meetup.com/account/comm/
Meetup Support: [address removed]
632 Broadway, New York, NY 10012 USA


People in this
Meetup are also in:

Sign up

Meetup members, Log in

By clicking "Sign up" or "Sign up using Facebook", you confirm that you accept our Terms of Service & Privacy Policy