Hi Wirt and all, I think it's a reasonable question to ask 'How important is competition in driving evolutionary change?'. Fitness is a measure of how well an organism is adapted to its environment. An environment is more than just competing species. I can imagine many systems where the way an organisms looks, acts, respires, metabolizes etc. has been shaped relatively little by competitors but relatively a lot by predators, mutualists, pathogens and abiotic environmental conditions. It may not be an either-or question but it certainly is a 'relative importance' question. Best.
Jeff H PS My own sense is that competition is not that important -----Original Message----- From: Wirt Atmar <[EMAIL PROTECTED]> To: [email protected] Date: Thu, 28 Feb 2008 22:01:45 -0700 Subject: Re: [ECOLOG-L] Evolution Population Ecology Competition or Adaptation Wayne Tyson asks: > I would like to know how many (what percentage of?) ecologists think > competition drives evolution or whether it's adaptation. The question isn't either-or. Competition for resources within a bounded arena results in adaptation. Darwinian evolutionary theory is composed of only five components: (i) a bounded arena, (ii) a replicating population which must eventually expand beyond the bounds of the arena, (iii) thermodynamically inescapable replicative error, (iv) competition for space in that arena among the inevitable variants, and (v) consequential competitive exclusion of the lesser fit. Darwinian evolutionary theory is an optimization algorithm. The most overt attribute of the process is the accumulation of increasingly appropriate behaviors within the evolving lineage of trials. "Adaptation" is simply the overt response to that evolution of increasingly appropriate behaviors. The agent of evolution is natural selection, which is mediated by the constant culling of the least appropriate phenotypes from the inevitable excess population locked within that finitely bounded arena at every generation. If you want to read a ponderously technical description of this process, written for engineers, you might look at: http://aics-research.com/research/notes.html When a process is understood well enough, and we do understand the Darwinian algorithm very well now, it can be exploited for engineering purposes. Indeed, that may be the ultimate test for how well we understand a process. I mentioned the other day that all sciences eventually become predictive, and that prediction is the only way we have of measuring how well we understand a subject, but engineering exploitation of a scientific discipline represents yet a higher level of understanding. There are now hundreds of engineering organizations employing Darwinian evolutionary methods to design structures and processes now. One of them is a group at NASA Ames Research Center, Moffett Field, CA, headed by Jason Lohn. One of the more interesting things that Jason's group has done recently is design the first spacecraft-flyable antennas using evolutionary methods: http://ic.arc.nasa.gov/projects/esg/research/antenna.htm The results of their design work appears at the bottom of the page. As Jason has said, "no matter how drunk you got an antenna engineer, he never would have designed anything that looks like this," but the evolved antennas have a higher gain and better angular coverage than do the best of all of the previously human-designed antennas. Leslie Orgel's Second Law, "evolution is cleverer than you are," now appears on more engineering PowerPoint slides than it does on those of biochemists, the audience for whom he originally meant the comment. Wirt Atmar
