In article <3oumuk$4ff at agate.berkeley.edu>, frauwirt at notmendel.Berkeley.EDU
(Ken Frauwirth (BioKen)) writes:
>In article <3ore5j$jhm at jhunix1.hcf.jhu.edu>, <Chris Thoburn> wrote:
>>In article <3or8or$5bp at agate.berkeley.edu>, frauwirt at notmendel.Berkeley.EDU>>(Ken Frauwirth (BioKen)) writes:
>>
>>Several points:
>> 1) Parasitism does not mean death. An organism may well carry a parasite
load and be perfectly able to survive.
>>Perhaps not for all parasites, but for many it does mean death, especially in
>immunocompromised hosts. And without an immune system, the parasite load
>might very well be higher (and fatal).
I agree...just remember it is not always true.
>>> 2) I do not agree with you that the FUNCTION of immune systems is to protect
>> an organism from 'undesirables'. I have always been bothered by this
concept, finding no reason at all to beleive that the immune system 'protects'
one from anything.
>>A problem with discussions such as this is that language often obscures the
>intended meaning. What I meant is that the end result is that a (if not the)
>major advantage of having an immune system over not having one is that an
>organism is far less likely to succumb to infection by pathogens. "Function"
>implies intent, and I do not believe that natural selection has conscious
>intent. Whether or not the *original* advantage conferred upon the first
>organisms to have an immune system was resistance to pathogens, well, that is
>anyone's guess. But it seems that the major detrimental effect of destroying
>the immune system (at least in mice and humans) is overwhelming
>susceptibility to infectious diseases (and perhaps cancer).
Resistance to being overcome by pathogens would be an advantage. "Function"
does not imply intent. There did not have to be an 'original advantage'.
>>> 3) I'm not sure that evolution can not be 'directed' under certain
>> circumstances. I think that perhaps many possible machanisms fall under the
>> broad category of 'evolution' and that some can indeed be focused.
>>Of course it "can" be directed (humans do it all the time - we call it
>breeding), but I meant that prior to such interventions (e.g. when the immune
>system was evolving), there was no conscious direction involved. If you had
>any reproductive advantage over other organisms in your niche, you outcompeted
>them. That might mean, "If you are better able to withstand invasion by
>infectious organisms, you'll have more offspring."
I agree, in context that I intended to convey that evolution can be directed.
Keep in mind that direct evolution is not the only mechanism.
>>> 4) The question of the reason behind the existance of an endocrine system is
>> quite possibly the same reason behind the existance of the immune system.
You
>> dishearten me by insinuating that it is a foolish or worthless question.
>> Blind faith has it's part in religion, but not science. A true Scientist
>> (with a capital S) questions everything and does not dismiss a particular
>> question as worthless simply because it is difficult to answer.
>>An interesting rejoinder, when you state "I don't believe that the immune
>system 'uses' any principles... I think that perhaps it simply exists, time
>passes, and things are different than they were before." That is (to me) a
>very un-Scientific approach. Biology is a very deterministic science -
>everything has a molecular mechanism. Things don't "just happen", but there
>is some logic: stimulus/response. If the immune system simply "changes" with
>no rhyme or reason, than to study it is an exercise in futility.
[snip]
>>> 'What' and 'How' are merely observation...'Why' is philospohy.
>>That is exactly my point - it is not Science. Science can only answer "what"
>and "how" ("How did the immune system evolve" is not the same connotation as
>"Why did the immune system evolve"). I love to discuss philosophy, but please
>do not disguise it as science.
>>>>>>>"What are the basic principles that immune systems use to differentiate
>>> between the Good, the Bad, and the Irrelevant?" (This, of course, being the
>>> question addressed by our "disappointing" exchanges of "unoriginal" ideas)
>>>>I don't beleive that the immune system 'uses' any principles or that it can
>>differentiate between Good, Bad, and Irrelevant. I think that perhaps it
>>simply exists, time passes, and things are different than they were before.
>>>>>"What are the weaknesses of different types of immune systems, and are there
>>> evolutionary considerations that might have maintained some of these
>>> weaknesses (allergies, for example)?"
>>>>Since I think that the immune system simply exists and does not discriminte
>>between self and non-self, allergies (and other so called weaknesses) simply
>>happen. This makes sense to me without the need to consider anything as a
>>weekness. Again, I don't think evolution 'considers' anything at all. It
just
>>happens.
>>>>As I stated above, I find it difficult to reconcile these views with a
>Scientific approach. The study of biology (or any science) has the underlying
>assumption that life (or physical) processes follow rules, and that we can
>work out at least some approximation of those rules, and that we can then
>apply those rules to predict phenomena. While I realize that chaos theoy and
>particle physics have a degree of "unpredictability" to them, people who
>study those fields realize that the question of "Where exactly is the
>electron" is not worth pursuing. If there is no consistent mechanism by which
>the immune system is induced to change (i.e things "just happen"), then its
>study *is* "worthless", at least to Biology (with a capital B).
I think that you have confused technology with science. Science is indeed a
philosophy (a way of thinking...) seeking to understand. Technology is more
concerned with the practicality of knowledge. While neither is better than the
other (one needs both), a true scientist generally asks 'why' and technologist
generally asks 'how' and 'what'. A true scientist would never consider when to
stop asking a question because it is not worth pursuing, but a technologist
would.
please excuse the delay, I have had trouble posting...
Chris Thoburn
