[extropy-chat] evolution / selection of cells within a single body / lifespan

[The Avantguardian]

--- Ensel Sharon <user at dhp.com> wrote:

> 
> Hello,
> 
> I am very interested in learning more about the
> concept of cells or
> mitochondria evolving, or facing selection pressure,
> within a single body,
> and within a single human lifespan.
> 
> Nick Lane speaks a little about this in his book
> _Power, Sex, Suicide_,
> but not that much.  I am wondering:
> 
> 1. If anyone can recommend some other sources/books
> that talk more about
> this idea/theory

Lots of academic stuff like immunology text books,
cancer biology books, articles like:

http://www.sciencemag.org/cgi/content/abstract/194/4260/23?ijkey=810a8276b318c3fbfb91f9c30f34c002eaa675e5&keytype2=tf_ipsecsha

http://ije.oxfordjournals.org/cgi/content/full/35/5/1165

The idea has been around for some time amongst
biologists. Unfortunately I don't know of any popular
books that explain the concept very well. 

 
> 2. If there is an accepted term used to describe
> this, that I obviously
> don't know.

"Clonal selection" (although this term is more often
used to describe adaptive immunology and tolerance)

Clonal selection: there are two versions of this idea,
one from immunology and the other from cancer biology.


The immunological clonal selection theory is about how
white blood cells over the course of your life time
*evolve* or alternatively *learn* to recognize self
from non-self (or traitors to the self) in order to
defend the body against diseases like viruses and
cancer. 

The clonal selection theory of carcinogenesis is the
theory of how cells mutate to become cancer cells,
gradually developing adaptations that allow them to
escape or overwhelm the body's defenses and commandeer
more resources for themselves at the expense of the
rest of the body.

Although if you get bogged down in detail, the two
forms of clonal selection may seem to differ but the
general theme is the same. It is an evolutionary arms
race going on between cells of the self, non-self
cells (microbes), and defector cells within the
context of a single organism's body during its life
span.      

Other terms I have seen used in the literature
specifically in regards to cancer cells are "somatic
evolution" and "clonal evolution" which are more
reflective of the constant Darwinian struggle going on
within your body.

In no other way is the illusion of "you" made more
apparent than when you learn that you are a collective
of factions competing with one another as well as
foreign invaders for the holy grail of another
sunrise.
In any case it is a facinating subject which certainly
deserves a book.





Stuart LaForge
alt email: stuart"AT"ucla.edu

"Believe nothing. No matter where you read it, or who said it, even if I have said it, unless it agrees with your own reason and your own common sense."- Siddhartha Guatama aka Buddha.

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