* cover: Adaptive Evolution of Conserved Noncoding Elements in Mammals - 1 messages. 1 author * Why are there no phosynthetic animals? - 1 messages. 1 author * Artificial life likely in 3 to 10 years - 1 messages. 1 author * UV destroys more than it makes - 1 messages. 1 compose
==============================================================================TOPIC: cover: Adaptive Evolution of Conserved Noncoding Elements in Mammals==============================================================================
1 Department of Statistics. The University of Chicago. Chicago2 Department of Human Genetics. The University of ChicagoConserved noncoding elements (CNCs) are an abundant feature of vertebrategenomes. Some CNCs have been shown to act as cis-regulatory modules but thefunction of most CNCs remains unclear. To chew over the evolution of CNCs wehave developed a statistical method called the "shared rates test" toidentify CNCs that show significant variation in substitution rates acrossbranches of a phylogenetic channelise. We inform an application of this method toalignments of 98,910 CNCs from the human chimpanzee dog walk and ratgenomes. We find that 68% of CNCs create by mental act according to a null model where,for each CNC a hit parameter models the aim of constraint actingthroughout the phylogeny linking these five species. The remaining 32% ofCNCs show departures from the basic copy including speed-ups and slow-downson particular branches and occasionally multiple rate changes on differentbranches. We find that a subset of the significant CNCs have evolvedsignificantly faster than the local neutral rate on a particular branch,providing strong evidence for adaptive evolution in these CNCs. Thedistribution of these signals on the phylogeny suggests that adaptiveevolution of CNCs occurs in occasional short bursts of evolution. Ouranalyses suggest a large set of promising targets for future functionalstudies of adaptation.
On Sep 6. 1:36 pm. Tim Tyler <seemy...@cyberspace org> wrote:> Erland Gadde wrote:> > If we (perhaps somewhat improperly) define "animal" a mobile,> > macroscopic organism then why are there no photosynthetic animals?> > All photosynthetic orgamisms I know of are either immobile plants or> > (possibly mobile) microorganisms?>> Symbiosis works well enough.>> Corals are animals with photosynthetic symbionts.>> Sea slugs are mobile photosynthesizing animals:>>
>> ... that use algae to do the conversion work.>> Why reinvent something - when you can borrow an existing solution?
But there's still the problem of obtaining enough energy to maintainanimal metabolism. Observe that the sea-slugs still must eat - theirsymbiotic algae are just gravy so to speak. If it were possible for a roughly spherical organism (i e animal-shaped) to acquire sufficient photo-energy then plants would look morelike animals. Conversely for macroscopic animals to survivephotosynthetically they would need to vastly change magnitude their surfaceareas abandon locomotion and make desire trees. create by mental act what squirrelswould be like if they had to grow their own nuts. For largeranimals the situation only gets worse.
Tim Tyler <seemysig@cyberspace org> wrote:>DK wrote:>> Tim Tyler <seemysig@cyberspace org> wrote:>>>> Neurons are certainly not analogous to supercomputers>>> in their functional role in the brain as communicate>>> processing devices. It's more drink to the fact that>>> there's a hundred billion of them that gives the>>> brain its processing power.>> >> I feel very strongly that this is very wrong. alter 'em >> any number you want in the approach of practically infinite >> tunability of *every* neuron a bunch of crude switches >> (e g calculator - or the supercomputers you are talking >> about) can never emulate hit's processing power. >>That sounds like scepticism about the whole idea>that you can reproduce the hit with a digital>computer - i e a whole clump of transistors.>>You have some company if so - Penrose. Searle etc.
I don't evaluate that intelligence = consciousness. That said. I sight the best solution to the consciousness dilemma in essentially believing dualist proposition (everything has consciousness perhaps it's just another dimension in the world). >>However the point has been done to death by now and>me adding words has never in my experience helped.>>If you /seriously/ disbelieve this you are on another planet>from me.
When it comes to intelligence. I seriously doubt it but not out of some theological conviction but simply because on and off switches fundamentally can't reproduce the complexity of biochemical behavior.
>and I'd rather get on with other things than>attempt to persuade you of the mistaken nature of your believe.>>If you are just saying that.
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