In August I spoke at the Chautauqua Institution as part of their celebration of Darwin and Linnaeus. I posted the written version of my talk back then, but I’ve just received the audio recording and thought some folks might prefer listening to it instead. I actually prefer it too, because whenever I give talks, I look at what I’ve written and revise it as I talk. You can listen to the talk right here on the handy Odeo player I’ve embedded at the bottom of the post. Or you can download it to listen offline.
December 22nd, 2008 at 7:09 pm
[...] [Update: You can listen to my talk here.] [...]
December 23rd, 2008 at 10:43 pm
Thanks Carl.
I will get that onto my iPod and listen to it the next time I am at work.
December 26th, 2008 at 12:01 pm
My question is this: what did Darwin get right? Other than sexual selection, (which is a mindful or otherwise intelligent choice) I rarely read of anythng of Darwin that he was right about. Natural selection may happen — the unfit may indeed get unselected — but who where is the scientific literature can we find that this is the reason populations evolve? Darwin’s assumption that differential breeding success was the CAUSE of evolution was premised on the notion that individuals did not have them the mechanisms to generate their own adaptations. He didn’t know that developing embryos could somehow (through their parents) perceive the outside world and then alter their traits accordingly. Darwin didn’t know about epigenetics or horizontal gene transfer or symbiosis or plastic phsiological responses. Adaptation happens one way or the other — not both. It either happens externally (via selection) or internally via individual mechanisms. If the latter is the case then selection (Darwin’s “dangerous idea”) is out of a creative job….it’s not the origin of species and it does little more than just stablize populations; in otherwords it’s just a conservative devise that basically does the opposite of what’s advertised; keeps populations from evolving.
Carl?
December 27th, 2008 at 1:32 pm
I’m not a biologist nor have I read Darwin’s texts, but I hear that he pretty much inaugurated the theory of evolution all by himself, recognizing and defining the process, proposing major mechanisms and testing it with a massive amount of examples. Oh, and he visualized and penned the first cladistic tree, didn’t he?
I’m fairly sure that this is trying to describe epigenetics, and I’m fairly sure it fails: “epigenetics refers to heritable changes in phenotype (appearance) or gene expression caused by mechanisms other than changes in the underlying DNA sequence“.
Seems mostly to be about development and its lasting effects on gene regulation, not about embryos able to “perceive” (how; and what is “perceiving”?) the environment.
That doesn’t sound quite right to me. Epigenetics is limited (see above); surely Darwin knew about symbiosis and surely it can be adaptive – in fact I believe I remember his successful prediction of an heretofore unknown pollinator for a flower with an exceptional long basket as an example of co-evolution, so score one for Darwin again; and acquired plastic responses are AFAIU evolved (i.e. not hereditary).
Even a layman as me can see that this description is utterly wrong – any mechanism affecting hereditary change, including stabilization, is part of the evolutionary process. Adaptation will respond to selective pressures, so if these pressures, say, change to another state from the putative stasis of yours it it will first ‘push’ the population (act for change) then ‘pull’ it (act for conservation) as regards the new state.
I’m sure the different strengths and applications of various mechanisms are discussed in between actually researching what is the case in individual cases. Be as it may, as the Loom itself has reported, adaptation is a well tested mechanism for bacterial evolution, such as macroevolution into new ecological species. (AFAIU bacterias are recognized against their niches, such as the media they can utilize.)
December 27th, 2008 at 1:46 pm
Sorry, I meant to spell it out in full after that: “so stabilization is an example of a population evolving”.
[Because to say that a mechanism "keeps populations from evolving" is IMHO blatant sophistry - it is wrong per the definition of evolution (as in "common descent", for example) which allows for observed stasis and/or stabilization.]
December 28th, 2008 at 12:02 am
Torbjorn Larsson,
You need to see the comment thread for Mr. Zimmer’s post responding to mail he received from creationists about the evolution of the face. The person posting as “tom” also posted there with similar derisiveness, rudeness, and lack of knowledge. A number of people tried to talk sense to him, but he rebuffed all with similar rudeness. He makes categorical claims about the falsity of evolutionary theory despite woeful lack of even cursory, fundamental knowledge of the topic. He also makes categorical claims about the paucity of evidence for evolution, despite having admitted in that thread to not having done any delving into the primary literature of papers published by scientists. He was given links to follow as well as some titles to go to as an introduction to some basics regarding evolution. He completely ignored them and then started talking about conspiracies between journalists and scientists to hide the truth about evolution. While your replies to “tom” are in good faith, know that he is not here in good faith, does not care to educate himself, and will show you no civility in your attempts to help him understand that of which he is completely ignorant. In short, you are wasting your time with him. He is not a serious individual at all, and is certainly not here to learn anything. If you go to that thread, you will see that he makes that abundantly and embarrassingly clear. Still, good for you for trying.
Yours,
Mel
January 8th, 2009 at 8:12 am
Darwin plagiarizes to Pierre Tremaux?
I leave you the link to scientific paper that it affirms that to the idea of allopatric speciation borrow of a book of Pierre Tremaux.
Trémaux on species: A theory of allopatric speciation (and punctuated equilibrium) before Wagner
http://philsci-archive.pitt.edu/archive/00003806/
Tremaux’s Book: Origine et transformations de l’homme et des autres êtres, 1865″ http://fon.gs/tremaux-book-google/
January 10th, 2009 at 11:00 am
[...] For Your Listening Pleasure: Darwin and Linneaus and the Web of Life [...]