nebula Posted February 22, 2011 Group: Royal Member Followers: 10 Topic Count: 5,823 Topics Per Day: 0.75 Content Count: 45,870 Content Per Day: 5.94 Reputation: 1,897 Days Won: 83 Joined: 03/22/2003 Status: Offline Birthday: 11/19/1970 Share Posted February 22, 2011 I'm not sure why where you got the idea of "all knowing" from. It wasn't explicit or implicit in what I wrote. Duh! I was getting my "omni" terms mixed up. Sorry about that. Omni-potent = "All power" OK, that makes more sense with what you said, then. The same type of initial cell developing into a skin cell, a nerve cell, a liver cell, and so on happens everyday. Genetic changes that affect development can have far reaching effects. Does the creation of something that never existed before, though, happen every day? Skin cells were pre-programmed. Nerve cells were pre-programmed. Liver cells were pre-programmed. Potorecptors on an organism that never had photoreceptors before is not the same as a liver cell having an altered function, for example. That would be like a baby being born with liver cells that can sense internal heat, or something like that. Yes, of course new organisms are created everyday? Ya know, little bunnies, birdies, and so on. That's not what I mean by new - new as in something that never existed beofre. Which is what has to have happened for evolution to take place as you all are saying it did. One day, no nerve cells in existence anywhere. Next day, a mutation takes place in the development of some creature somewhere that results in the first ever primitive nerve cell. You seem to have this idea that somehow cells are constrained to only develop in one manner, that is not the case. No, but your argument shows no sign of understanding the complexity of the differences between an epithelial cell and a nerve cell. Link to comment Share on other sites More sharing options...
nebula Posted February 22, 2011 Group: Royal Member Followers: 10 Topic Count: 5,823 Topics Per Day: 0.75 Content Count: 45,870 Content Per Day: 5.94 Reputation: 1,897 Days Won: 83 Joined: 03/22/2003 Status: Offline Birthday: 11/19/1970 Share Posted February 22, 2011 Not sure if there's any research that can satisfy your idea of "completely new" (I doubt this happened in one mutation), but off the top of my head one that comes into mind is a mutation that caused the fingers of the bat to elongate giving them their wings (prx2 gene, I think, this is off of memory). That's not as dramatic as a cell that never existed before, with a function that never existed before, coming into being. There was also an experiment where scientists changed a gene of a sea squirt [embryo] that changed the development of muscle tail cells into heart cells, creating a fully functional two-chambered heart when it only had one chamber before. Not exactly as dramatic as going from epithelial to nerve, but we did go from one type of muscle to another type that performed a newish function, at least to the cells themselves. Key here - "scientists changed the gene." Evolution implies no control by an intelligent source. You aren't really changing one cell type to another type of cell, you are changing the developmental pathway of certain cells before they differentiate. Did you read my last post? There are a lot of differences between an epithelial cell and a nerve cell. Nerve cells require the ability to produce and action potential, and that requires the inside of the cell membrane to have a specific "resting potential" charge, ion channels, additional or formation of NA-Cl pumps, and enough sodium and potassium for the action potential to be generated down the plasma membrane. Yes I read your post. We aren't taking a fully formed epithelial cell and changing it into a nerve cell. I'm talking about taking a cell that has yet to differentiate and changing it's pathway (that's what happened in the sea squirt experiment). A pathway that never existed before, though? Can all of this organization take place in some early embryonic mutation? Yes. I wouldn't say it happened in one mutation, I don't know and it seems rather unlikely. From what I understand it takes just two molecule complexes to be able to sense the light and start signal transduction. You have nerves attached all along your skin, if this eyespot happens to be on top of one of those nerves you have the makings of a primitive eye. It might have taken a few hundred or even a thousand generations to get everything together, but there's really nothing stopping it from happening. So for all these generations a useless trait was spreading throughout the population until one baby luckily had a developmental mutation that just so perfectly added to the useless trait to something functional? Link to comment Share on other sites More sharing options...
nebula Posted February 23, 2011 Group: Royal Member Followers: 10 Topic Count: 5,823 Topics Per Day: 0.75 Content Count: 45,870 Content Per Day: 5.94 Reputation: 1,897 Days Won: 83 Joined: 03/22/2003 Status: Offline Birthday: 11/19/1970 Share Posted February 23, 2011 And I still have yet to hear any of you explain the change in the complexity and make-up of the cell membrane and other such things in the process of this simplistic change. The DNA had never been programmed before to have the ability to send signals down its plasma membrane via ion exchange and ion channels and gated channels. And yet in a simple mutation at the early developmental level, these things come to be for the very first time in existence? Not buying it. Link to comment Share on other sites More sharing options...
nebula Posted February 23, 2011 Group: Royal Member Followers: 10 Topic Count: 5,823 Topics Per Day: 0.75 Content Count: 45,870 Content Per Day: 5.94 Reputation: 1,897 Days Won: 83 Joined: 03/22/2003 Status: Offline Birthday: 11/19/1970 Share Posted February 23, 2011 Are you saying that the first neuron cells were these eyespots? The eyespots on singke-celled organisms aren't cells, remember? How did you come to this conclusion? So pray tell, what was the first nerve cell? Link to comment Share on other sites More sharing options...
nebula Posted February 23, 2011 Group: Royal Member Followers: 10 Topic Count: 5,823 Topics Per Day: 0.75 Content Count: 45,870 Content Per Day: 5.94 Reputation: 1,897 Days Won: 83 Joined: 03/22/2003 Status: Offline Birthday: 11/19/1970 Share Posted February 23, 2011 Why would a proto-nerve cell have to operate in the same manner as the nerve cells we see today? The answer is, it doesn't and probably did not. So pray tell, what is a proto-nerve, and how did it function? Link to comment Share on other sites More sharing options...
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