Re: a reply to river wind
Originally posted by paulsamuel
I found it difficult to understand your response to my suggestion that your argument appeared to be telological, however I assure you that evolutionary processes are NOT goal directed OR progressional.
I agree.
is really not a valid argument becuase the exact opposite can be said and would be more correct, i.e., if it wasn't the case, then we wouldn't see so many organisms (many more orders of magnitude greater than sexual reproducers) that reproduce this way. However, biologically, you make a valid point. Theories on why sexual reproduction came about can be found in published work of John Maynard Smith and Richard Dawkins (The Selfish Gene). One theory is that sexual reproduction arose to provide genetic variability. Regardless of these theories, the consequence of reproduction is to get your genes into the next generation. One can regard fitness as how successful an individual is in getting genes into the next generation, the most fit being the individual with the most genetic representation in the next generation. Therefore the fittest individual is the one with all his genes, unaltered, in the next generation.
this assumes that the surrounding biological and non-biological environments remain stable between generation, which is usually not the case. The one who passes on the genes which are the most effective in dealing with the next generation's set of environmental conditions is the most successfull. Genetic success must be viewed with more that a single generation in mind. If I have 3,000 children, but all of them have sterile children, I am genetically a failure in the long term, despite my initial success.
when I stated that 'mistakes in copying are incidental to the process,' I meant the process of replication, i.e. hundreds of millions of cells copying hundreds of millions of bases of DNA hundreds of millions of times per hour, where mistakes are bound (and I mean this literally) to happen. to which you replied,
and I would ask, where do you think these mistakes are coming from?
from the methods you mention. However, they are not incidental, they are integral. Many animals control their rate of nucleotide reproduction error more than others- this tells me that those who do not have checks to the same degree did not have an evolutionary drive to develope them. Therefore, the mutation rate seen in animals without extensive error-cheecking systems is as important to their adaptation and survival as reproduction itself.
You appear to be mixing selective advantage of the parent and the offspring. Perhaps it would be an evolutionary advantage of the offspring if the parent dies, but this does not mean that it's advantageous to the parent that it dies, and it appears that this is what you are asserting...
I do mix these things, and that is because that after years of biological study, I have come to the conclusion that in many cases, evolution has worked itself tot he point where the boarder between the well being of the parent and the well bein gof the offspring is very blurred. In many cases, the well being of the offspring *is* the well being of the parent, such as in many mullusc, fish, and insect species where the parent individual dies right after mating.
What would be the purpose of mating if the individual was not going to die down the road? what would be the purpose of dying if an individual was not going to mate? After thinking about these two questions, it appears to me that death would not stand on it's own as a useful thing beyond the first generation without reproduction. Reproduction can stand on it's own two feet w/o death, but is not sustainable in that arrangement beyond a few generations (given a limited-reasource environment). Assuming nothing about why both things exsist, it is feasable that they both came about as evolutionary factors for the reasons I posted before.
Unless Death from "natural cuases" is simply due to the body wearing down over time. However, studies over the past decade with mice suggests that this is not the case. Aging seems to be controlled genetically.
iteroparity vs. semelparity.
I have studied these, but it was years ago. I'll read up on them again tonight, in case I have forgotten something important (it happens alot).
thanks for the rebuttal! always fun to track down these thought paths!
As for computer viruses and AI- I would say that they are not naturally alive, but that there is less and less noticably different between the two. As for computer viruses, I would say they would only count as alive if God exsists. Then both Computer viruses and biological life would have been created by intelligent being, with set directives. If God does not exsist, then I would say that computer viruses are not alive because they only reproduce because they were instructed to do so by their creator, with no reason or drive to do so beyond that. If I write a computer virus programmed not to replicate, then it won't.
Biological viruses, according to my undergrad biology textbook, are cosidered alive only when they are activly infecting a cell (during reproduction). At any other time, they are not considered alive. That seems like such a logical strech to me, I feel that "life" as a word, needs to be re-defined. As was mentioned earlier, there was a time when cells were the smallest atom of life. I feel that we know anough now to say that cells are *not* the basic building block of life, yet for some reason, we refuse to let go of the idea.
A incredibly complex robot which can avoid the obstacles in it's changing environment it's something great, but we cannot say the robot it's evolving when it avoids an obstacle; it is avoiding an obstacle, not evolving.
1)incredably simple robots, based on insect design can avoid objects
2)adaptation ( on an individual level) and evolution differ by only two things: the scale on which they act, and the method through which they act. Adaptation on an individual level works through chemical memory (a simple shift in chemical pathways via an outside influence) or conscoius/unconscious memory. In either cases, an individual who can adapt best to its environment is the most likely to survive and reproduce.
Evolution works on a genetic level within an overall population. However, it is still all about "who can adapt best to its environment is the most likely to survive and reproduce." "the individual" is just changed to "the species"
No, a robot that avoids an obsticle is not evolving. But if it learns how to avoid that object, and remembers for later use, it is adapting. And if it can then pass that knowledge on to its ofspring by changing the offsprings basic form or functionality, then it's kind is evolving. If it passes that knowledge on without changing the physical or the programmable form/function of its offspring in some way - if it passes it on by teaching alone - then its kind are not evolving either. They are just collectively learning.
