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Politics : Evolution -- Ignore unavailable to you. Want to Upgrade?

To: TigerPaw who wrote (68664)	9/22/2015 5:57:45 PM
From: 2MAR$	Read Replies (1) \| Respond to of 69300

I think it's important to point out the context in which continental drift is important. Life began on this planet 4 billion years ago and for most of that time it didn't change very quickly Agreed, also with timelines for aerobic replacing anerobic , vast subject & slow change, have come to think life is a very rare event but somewhat inevitable. why the surface of the earth broke up into plates. One hypothesis is that the interior contracted as the planet cooled and the surface naturally cracked, while another posits that a large meteorite shattered the surface on impact. And common sense & intuition are contained in both. This expression 'Big Bang of Evolution' has caught on, you did see rebuff of Meyers, this contains a key Message 30233932 The main argument of Meyer is the mathematically impossible time scale that is needed to support emergence of new *genes* which drive the explosion of new species during the Cambrian period. Marshall points out that the relatively fast appearance of new animal species in this period is not driven by new genes, but rather by evolving from existing genes through "rewiring" of the gene regulatory networks (GRNs). This basis of morphogenesis is dismissed by Meyer due to his fixation on novel genes and new protein folds as prerequisite of emergence of new species. The root of his bias is his "God of the gaps" approach to knowledge and the sentimental quest to "provide solace to those who feel their faith undermined by secular society and by science in particular

To: TigerPaw who wrote (68664)	10/5/2015 12:57:43 AM
From: 2MAR$	Read Replies (1) \| Respond to of 69300

Evolution of Evolvability in Gene Regulatory Networks (PLOS: Computational Biology) http://journals.plos.org/ploscompbiol/article?id=10.1371/journal.pcbi.1000112

To: TigerPaw who wrote (68664)	10/6/2015 6:41:56 PM
From: 2MAR$	Respond to of 69300

after 3 1/2 half billion years life on this planet was still all single cell organisms...... Single cell organisms from anerobic to aerobic as you mentioned. Remembering there were 1000's of different cells that had evolved & spread, adapted & occupying about every concievable niche & habitat imaginable, extremophiles to stromatolites. Eventually see a long colonization period turn to segmentation, the first worms perhaps, letting the imgination stretch a bit of course. Quite a foundation being laid, genetically speaking.

To: TigerPaw who wrote (68664)	10/6/2015 6:57:40 PM
From: 2MAR$	Respond to of 69300

I suppose for Brumar seeing all those plate shiftings in that video we can deduce happening was just a bit too much reality, but your points are excellent. The breaking up, drifting plates produced so many shifting habitats, from shallow inland seas, lakes, river, mountain, ever changing land mass , so speeding up the process of adaptation & change as the land itself becomes colonized. Within oceans themselves we see life stratified, go down past 2000ft whole new worlds open up, there are the lovely siphonophores representing colonial organization we find existing there siphonophores.org " Siphonophores challenge us to think about what we mean when we call something an individual, a concept that we usually think of as being quite straightforward. Is a single zooid or an entire colony the siphonophore “individual”? The answer is that you have to specify what features you are interested in before you can expect a meaningful answer. Do you mean ecologically? The entire colony functions as a single organism whether it is predator or prey. So the colony is an ecological individual. The same can be said for behavior. How about evolutionarily? There are two different components to this question. If we ask how evolution acts on siphonophores now, they are individuals. All the parts of the colony are genetically identical and the colony lives or dies as a whole (except for the eudoxids described later) . So siphonophores are evolutionary individuals with respect to how natural selection shapes them today. The other way to look at evolutionary individuals is by descent. We can do this by taking a look at two animals and asking which structures descend from the same feature of a common ancestor. Just as this leads us to recognize that bat wings are modified arms, it shows that siphonophore zooids are polyps and medusae, structures that can be free living animals in other species. So this argument leads to the conclusion that the zooids of siphonophores are individuals. This is not contradictory to our previous conclusions, we are just looking at a different feature of individuality."