Re: Function, Symbiosis, Parasitism

["Tim Gwinn" <***>]

John wrote:
> So is agriculture a parasitic, or a
> symbiotic arrangement?
> (I think a good question of the day).

That's a great question!

I'm going to try to approach it from Rosen's comments in chapter 21 of
"Essays". This involves some partial differential equations, but they are
not very hard. (Apologies in advance to those who are not partial to math
(pun intended!)). In this plain text, I'll use "6" to indicate a partial
differential, and "x#" to indicate "x-dot" ("a change in x").

We start with two separate individuals, with their own genomic identities,
a,b. (In this case, 'genome' is a general term for identity, and is not
automatically identified with DNA.)

They each have some behaviors, x#, y#, which are changes in state x,y of the
respective individuals.
They each have their respective environments, F,G.

So, bypassing the preliminary discussions (see ch. 21) survival is
associated with:
       6(6a/6F)/6x# < 0
which in plain language means that changes in genome (6a) per changes in
environment (6F) are inhibited by virtue of offsetting changes in behavior
(6x#).

A cooperative or symbiotic relationship is therefore when both of the
following are true:
       6(6a/6F)/6y# < 0        6(6b/6G)/6x# < 0
In this case, both species behaviors are mutually inhibiting changes in the
other's genome.

Similarly, Rosen descibes a competitive relationship as:
       6(6a/6F)/6y# > 0        6(6b/6G)/6x# > 0
where the behaviors of each species is working to promote changes in the
other's genome (i.e., in broadest terms: destroy the other's identity).

So, what is parasitism? I suspect it can be said to be the following case:
       6(6a/6F)/6y# < 0        6(6b/6G)/6x# > 0
where there is a one-sided relationship. One species promotes genome
preservation of the other, but the other's behavior is working to destroy
the genome of the first.

Where does agriculture fit in? If it is, say, chickens raised for eggs, then
that would pretty well fit in with the symbiotic scenario: there are
behaviors on both sides that provide mutually beneficial tradeoff of
resources while preserving both sets of individuals.Even if we shift the
discussion from individuals to 'generations of individuals' of the same
genome, it is likely that the situation would remain in the symbiotic realm.
That is, the forcing of production of nonfertilized eggs (which would by
itself appear to be a negative influence on generational success of the
chicken's genome) will be offset by the humans long-term cultivation of the
species. But this notion also shifts the idea of 'genome' from an individual
to a species.So, shifting to a generational timeframe cannot be directly
related to the genomic success on an individual level.

In the case of, say, raising chickens as food, it seems to be a parasitic
relationship if we only consider the timeframe up until the chickens are
killed: the chickens are parasitic on the humans. (Granted, we humans have
set up the initial conditions intentionally to make it so, but I thought it
was an interesting point.) The chickens provide nothing for the humans, and
instead are a potential source of harmful waste, disease, etc.

If we switch to a timeframe to include just the killing or harvesting of the
chickens (and thereby changing the particular behaviors x# under
consideration), we see that the situation is reversed: now it appears the
humans are parasitic on the chickens (i.e., killing a chicken is definitely
bad for its genomic identity!). But wait: the chickens behaviors (which
occur only while it is alive) are no different than before. I propose that
the situation has become one of competition, where both species (as living
entities trying to preserve their genomic identity) are negative influences
on the other. Its just that the "competition" is decidely one-sided, and for
the chickens, their "goose is cooked", so to speak.

If we use a more inclusive timeframe that covers both situations (and both
sets of behaviors), then what is the nature of the relationship? I propose
that it is essentially the same as the situation just described above; that
is, one of competition. The chickens, while alive, are a negative genomic
influence on the humans, and the humans overall behavior is negative in that
it ultimately leads to the demise of the chickens. I think it is a case
where it is a "battle for survival", but the game is rigged.

I had not expected to come to this conclusion, because commonsensically,
after we kill the chicken we get something from it, so there is some feeling
of some kind of reciprocity. However, the getting of meat occurs *after* the
genomic relationship has ended, so there is no reciprocity *within* the
context of a relationship between genomes.

Since agriculture refers to a timeframe *more inclusive* than the genomic
relationship itself, thereby also referring to the non-living material
(carcasses) and their use to us, it seems as if the appropriate term for
agriculture is simply "technology". That this technology includes other
living organisms as part of its process is, in a sense, incidental to the
overall situation. So, agriculture is a case where biological organisms are
*utilized* as part of an overall process to generate some end-product. The
biological organisms are "metabolized" by the processes in the technology to
render a food-product.

Regards,
Tim

> -----Original Message-----
> From: ROSEN Forum [mailto:*** Behalf Of John M
> Sent: Thursday, July 10, 2003 9:20 AM
> To: ***
> Subject: Re: Function, Symbiosis, Parasitism
>
-snip-
>
> As I 'taste' the two words again, I would deem "parasitic" as
> using (feeding
> on) the 'host' while "symbiotic" is living together, maybe feeding on the
> same stuff. The latter is IMO a 'mutation' in the form of living, like a
> partnership, in which the partners get not only used to each
> other, but also
> adjust to the togetherness.
>
> This is the process, how I deem 'symbiotic' the development of eukaryotes,
> from associating prokaryotes (one immerging to form the nucleus) and the
> other keeping the 'outside' structure. Other prokaryotes also joined the
> corporation, forming e.g. mitochondria.
> Then such monsters joined together in masses and formed us
> (give or take a billion years).
> Parasites, however, are smarter (or are they?) they eat what they
> get, don't
> save the chances, even if killing the host tat feeds them.
> More complex systems are e.g. the symbiotic parasites, like ants, with
> insects: they keep them alive, feed them, for food. Same as a farmer does
> with cattle or chicken, even crop. So is agriculture a parasitic, or a
> symbiotic arrangement?
> (I think a good question of the day).
>
> Regards
> John Mikes