Jochen, That concept of alternating opportunistic and constrained developmental phases, 'relaxed' then 'fierce' selection regimes, sounds like a statistical version of the behavioral model that growth begins from minute beginnings in an environment without constraint except itself. When that kind of growth exhausts its initially unlimited opportunities and runs into constraints then integrating with an environment becomes the selective test. That switch from just freely expanding on the past to adapting in relation to emerging future constraints corresponds to immature growth followed by maturation at climax (¸¸.´¯¯) and their very different selection regimes.
The behavioral 'trick' needed to make that statistical idea into a functional description of a new mode of evolution is letting the system be active partner and the environment a passive one. If the system actively explores its environment, just like you see virtually all living things are visibly doing whenever they're not sleeping, then the form of the system doesn't need to be present in the environment before the system develops. That's always been the real undiscussed problem with the normal Darwinian model. It's that individual exploratory habit of a system that makes opportunistic development such as Deacon describes physically possible. That's what my plankton paper shows is happening with G. tumida, a series of progressive evolutionary spurts and collapses on the way to the stabilization of a new form, clear active individual behavior in a passive environment. Phil > -----Original Message----- > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On > Behalf Of Jochen Fromm > Sent: Monday, October 06, 2008 3:34 PM > To: The Friday Morning Applied Complexity Coffee Group > Subject: [FRIAM] Relaxed selection > > One of the things I am interested in is how nature > creatures complex things. The latest New Scientist > (from 27 Sep. 2008) has an article named "As if from > nowhere" about the topic of "relaxed selection", a > concept invented by Terry Deacon. Terry Deacon is > an anthropology professor at Berkeley. > > According to Deacon, relaxed selection is a special > form of natural selection, where the selection > pressure and the competition is low (i.e. where > natural selection itself is nearly absent), and the > variety of traits which are able to survive and > reproduce is high. When the selection pressures lift, > genomes go wandering and new, unexpected traits may > arise. I think if there is a "relaxed selection", > then one can also speak of a "fierce selection": > a natural selection with fierce competition when > the climate is harsh and the food is sparse. Under > this conditions only the best, well adapted individuals > survive. > > Does natural selection occurs in different degrees? > During "relaxed selection", the system enters an > exploration phase: the chances of finding new > configurations, traits and features are higher. > The selection pressure for a species to remain > in the corresponding niche is lower. > During "fierce selection", the system enters an > exploitation phase: chances of optimizing existing > configurations, traits and features are higher. > The selection pressure for a species to remain > in the corresponding niche is higher. > > What do you think of "relaxed selection" ? > Is Deacon onto something? > > -J. > > > > > > ============================================================ > FRIAM Applied Complexity Group listserv > Meets Fridays 9a-11:30 at cafe at St. John's College > lectures, archives, unsubscribe, maps at http://www.friam.org ============================================================ FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org
