Re: Senescence and death as properties of life?

[Dan Fiscus <***>]

Judith Rosen wrote:
snip
> *Incidentally, it is worth noting that all organisms seem to have more 
> than their own individuality encoded as "self"-- there's clearly a 
> species aspect to the definition of "self." This is more visible in 
> organism species which are dependent on sexual reproduction because each 
> gender clearly has the other encoded into it as well. What this means is 
> that if a species has two genders, any individual organism isn't really 
> "whole".*
snip

Judith,

Great point and I think we could add the other "missing/implied/other
half" aspect that functional types are similarly interdependent and not
whole taken alone. My same old autotrophic and heterotrophic dialectic.
In RR speak I'd go as far as to say that life = organism is not truly closed
to efficient cause since any organism requires an animated, active other
to participate in efficient cause. A coupled cooperative unit with both
autotroph and heterotroph on the other hand (but we'd also have to
cover the genders if a sexual community) is closed to efficient cause and
does not require other animate, active agents to survive long term. This
more whole life unit only needs abiotic/physical inputs, energy, matter,
etc.

As you say, self is complex, has more than one model or representation,
even within a single organismic self. I have recently re-started use of
these quotes to aid my thinking, to distinquish between 1) an organismic
self and discrete or particulate/localized life form and 2) a community
or ecosystemic self and continuous or extensive/non-localized life form.
The key modifier that goes along with the different definitions or models
is "sustained" as in long term or open-ended in time.

O'Neill et al. (1987)

"...define ecosystems as the smallest units that can sustain life in 
isolation
from all but atmospheric surroundings. However, one is still left with the
problem of specifying the area that should be included."

Morowitz (1992)

"sustained life is a property of an ecological system rather than a single
organism or species."


For this life and self of the community or ecosystem, death is an integral
aspect as you suggested too. Whereas at the scale or focal self of life the
organism a cell/organism is either alive or dead, at the scale or focal
self of the community/ecosystem this form is always both alive and dead.
Part of the ecosystem depends on detritus, soil, organic matter, etc. and
this is "dead life". Crucial to ecosystem function and the capacity for
open-ended life operation.

Dan


Morowitz, H.J. 1992. The Beginnings of Cellular Life: Metabolism
Recapitulates Biogenesis. Yale University Press. New Haven, CT. USA.

O'Neill, R.V., D.L. DeAngelis, J.B. Waide, T.F.H. Allen. 1987. A
Hierarchical Concept of Ecosystems. Princeton, NJ: Princeton University
Press. 253 pp.