URTH |
Date: Mon, 20 May 2002 01:03:20 -0500 From: Jeff WilsonSubject: RE: (urth) Liev's Postpostulate > From: > "Dan'l Danehy-Oakes" > Jeff Wilson claims that > > > Dollo's law is crap; it's violated by marine mammals, and > > moths that alight on trees in once-polluted areas. > > ...well, no; it isn't. > > In the case of peppered moths, no lost organs are reappearing; > the a:A balance of certain alleles is shifting due to natural > (or, I suppose, semi-artificial) selection. The "dark" genes > had always been present as a minority in the "gene pool," became > a far more prominent proportion of the gene pool when industrial > pollution caused the trees they sit on to become darker in color, > and once again became less common as pollution control allowed > the trees to regain their former light color. The basic papers > on this, by Kettlewell's and Haldane, are both easily available > in the Oxford reader on "Evolution," edited by Mark Ridley. > > In the case of marine mammals, what has happened is that the > lost organs have exactly failed to reappear -- all marine > mammals still must come to the surface to breathe; no gills > have reappeared. And, while the modified fins we call legs have > re-modified themselves to a more fin-like structure, this isn't > a case of anything lost reappearing. The only thing that might > be considered as a reappearance is the dorsal fin on some marine > mammals; I don't know enough about how those evolved to give a > legitimate answer to this. In that case, I sit corrected but I don't see the relevance; the function returns even if the anatomical detail doesn't. The Frenchmen don't give the suspected abos a medical exam, they test their limbs' function. Human hand or polymorphed pseudopod, if it can make nets it ought to be able to work a shovel. -- Jeff Wilson How Am I Posting? 1-800-555-6789 "If your SecOp can see you, so can the enemy." -Cpt Law --