Posted by
Gus Koehler on
URL: http://friam.383.s1.nabble.com/Cambrian-Explosion-tp521557p521564.html
You might find these references helpful:
Muller and Newman, Origination of Organismic Form.
Peterson and Parker, Ecological Scale.
Kalona and Lamb, Evolution in Four Dimensions.
Gould, Ontogeny and Phylogeny.
McNamara, Shapes of Time.
Edelman. Topobiology: An Introduction to Molecular Embryology.
Gus Koehler, Ph.D.
Principal
Time Structures
1545 University Ave.
Sacramento, CA 95825
916-564-8683, Fax: 916-564-7895
Cell: 916-716-1740
www.timestructures.com
-----Original Message-----
From:
[hidden email] [mailto:
[hidden email]] On Behalf
Of Jochen Fromm
Sent: Monday, March 13, 2006 11:13 AM
To: 'The Friday Morning Applied Complexity Coffee Group'
Subject: Re: [FRIAM] Cambrian Explosion
There is no doubt that environmental changes and chemical/physical stress
are among the causes for the
Cambrian explosion (Snowball Earth, glaciation, etc.). Certainly there is a
connection between "emergence" and "extinction", between complexity and
catastrophes. My question was more about the "how" (how does the
underlying code define the development of individuals?
is there such a code for the body plan?) and
less about the "why".
The form or "architecture" of plants for example can
be described well by fractals, IFS and L-Systems. Skeletons
and animal bodies have a certain amount of self-similarity,
too: a typical modern animal body has a certain amount of limbs
(2-6 legs or arms), and each limb has further sub-limbs
(2-6 toes or fingers). Therefore it must be possible to
describe bodies and their development with simple iterative
rules. I wonder what kind of rule set or code is really used?
The "three-lobed" trilobite for example, one of the first animals that
appeared in the Cambrian period has a very
simple repetitive head-body/thorax-tail structure, where the body is
composed of many similar repetitive segments.
http://en.wikipedia.org/wiki/Trilobite-J.
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