Posted by
Louis Macovsky, Dynamic BioSystems on
URL: http://friam.383.s1.nabble.com/Cambrian-Explosion-tp521557p521562.html
Here is a novel interpretation from Jorge Herkovitz, first talked to him
about this at a Society for Environmental Toxicology and Chemistry
conference in 2001.
http://www.findarticles.com/p/articles/mi_m0CYP/is_12_109/ai_82551842>From the first paragraph I pasted the following:
Present-day biodiversity, estimated to comprise more than 100 million
species, has developed in around 4,000 million years on the basis of the
ability of life forms to adapt and multiply at a rate that surpassed
extinctions. Species, including humans, depend on the ecosystems that have
operated with no or minimal human intervention up to recent years. Recent
extinction rates are 100-1,000 times their pre-human levels in taxonomically
diverse groups from widely different environments. Moreover, it is accepted
that if all species currently endangered become extinct, then future
extinction rates will be 10 times recent rates (1). Although chemicals are
the basic units for the development of life, it seems meaningful to take
into account Paracelsus' statement that "all things are poison and nothing
is without poison." From this perspective it seems obvious that chemical and
physical features have been considered driving forces of evolutionary
processes from the beginning of recorded history. Estimates suggest that the
current world production of chemicals is 400 million metric tons. Almost 11
million naturally occurring or man-made chemicals have been identified in
the CAS Registry File, although only a small portion of them is commercially
available. I would like to present the hypothesis of a direct link between
chemical stress and a major mass extinction process, the Cretaceous-Tertiary
(C-T) event, with the aim of providing a more holistic view on the potential
of chemical stress on the evolutionary process.
Lou
----- Original Message -----
From: "Jochen Fromm" <
[hidden email]>
To: "'The Friday Morning Applied Complexity Coffee Group'"
<Friam at redfish.com>
Sent: Monday, March 13, 2006 4:21 AM
Subject: [FRIAM] Cambrian Explosion
>
> You have certainly heard of the Cambrian explosion.
> It is used to describe the sudden appearance of a
> huge variety of fossil organisms with hard skeletons
> at the beginning of the Cambrian Period.
>
http://en.wikipedia.org/wiki/Cambrian_Explosion>
> What are the most plausible explanations you know?
> If it is some form of strong emergence, there must be
> a code behind it, a code which specifies the spatial
> organization of the body and the body plan for complex
> organisms with hard shells and skeletons.
>
> Since the body is formed during the embryonic
> development, it must be an embryonic development
> code, a recipe for builing multicellular structures.
> How does this code look like ? Is it similar to fractals
> and iterated function systems (IFS) ? Is it more related
> to the 4-symbol alphabet of the genetic code, to the
> 20-symbol protein alphabet, or more to cell types
> (possibly attractors of genetic regulatory networks) ?
>
> -J.
>
>
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