Lukaisimpa huvikseni kirjan nimeltä
"Bioinformatics for Dummies"(kirja siis oli juuri minua varten kirjoitettu)
Luku "A Survival Guide to bioinformatics"
Sivu 196.
"The protein world:Kingdom or condominium?
The discovery of domains in the 1980s was a clear demostration of something everybody had strongly suspected from time Darwin started taking vacations in the Galapagos island:NATURE IS SMART BUT LAZY!
You can be sure thet if there is a way to turn an old thingy in a brand new gizmo it needs,nature will find it!
Protein domains are a wery nice illustrations of this principle, Propably no more than a few thousand diffrent types of domains exist. Nature builds an new proteins with this collektion like you used to play with your LEGO-pricks. Each type of domain is a special kind of prick characterized by very stable shape. The main diffrence between a LEGO-prick and a domains that evolution can easily modify an existing domain to accomodate a new function.
These modifications don't change the overall fold of the domain,but they involve mutations that can partly change some of the domain properties-its a binding affinity,for excample."
Luku "Becoming a specialist:Advanced Bioinformatics Techniques"
Sivu 386
"When we think evolution,we tend to think of natural selection,survival of fittest,struggle for life,and all these testosterone-loaded consepts. In molecular therms,gurus name this neo-darwinism. This popular theory states that the only reason mutations stay in a population is bekouse they are helpful and increase the fittness of the individuals that carry them. This ancient theory doesn't account very well for synonymous mutations or other harmless DNA-alterations.
In the sixties,the increased availability of molecular data led to the ellaboration of neutralism by Kimura. Naturalism,also known as a neutral theory,challenges neo-darwinism by stating that most mutations are either lethal or neutral. Everybody agrees that lethal mutations are disposed right away,but,for neutralists,in the fact that a new non-lethal mutation spreads or not in the population depends mostly on change. Even if these mutations are advantageous chance is the driving force. Keep in mind that neutral mutations aren't necessarily silent at the protein level and that they can also be mutations that slighly change a protein without altering its function. Of course,after these harmless but useless mutations are fixed,they can also find a niche and give some advantage to the individuals that carry them,later on.
Neutralism is a wery poverfull theory becouse it accounts very well for the way in which species build their adaptation potential before they need it.
If you are doing phylogeny,these neutral mutations are really the ones you're intrested in. You don't want to see adaptation;you want to measure evolutionary distances and the best measure of evolutionary distances you have is counting number of random and quasi-neutral events that occured on your sequences since they separated their ancestor. You can think of these mutations like each tick of a clock that been working,one mutation at time,for a million years."
"Bioinformatics for Dummies"(kirja siis oli juuri minua varten kirjoitettu)
Luku "A Survival Guide to bioinformatics"
Sivu 196.
"The protein world:Kingdom or condominium?
The discovery of domains in the 1980s was a clear demostration of something everybody had strongly suspected from time Darwin started taking vacations in the Galapagos island:NATURE IS SMART BUT LAZY!
You can be sure thet if there is a way to turn an old thingy in a brand new gizmo it needs,nature will find it!
Protein domains are a wery nice illustrations of this principle, Propably no more than a few thousand diffrent types of domains exist. Nature builds an new proteins with this collektion like you used to play with your LEGO-pricks. Each type of domain is a special kind of prick characterized by very stable shape. The main diffrence between a LEGO-prick and a domains that evolution can easily modify an existing domain to accomodate a new function.
These modifications don't change the overall fold of the domain,but they involve mutations that can partly change some of the domain properties-its a binding affinity,for excample."
Luku "Becoming a specialist:Advanced Bioinformatics Techniques"
Sivu 386
"When we think evolution,we tend to think of natural selection,survival of fittest,struggle for life,and all these testosterone-loaded consepts. In molecular therms,gurus name this neo-darwinism. This popular theory states that the only reason mutations stay in a population is bekouse they are helpful and increase the fittness of the individuals that carry them. This ancient theory doesn't account very well for synonymous mutations or other harmless DNA-alterations.
In the sixties,the increased availability of molecular data led to the ellaboration of neutralism by Kimura. Naturalism,also known as a neutral theory,challenges neo-darwinism by stating that most mutations are either lethal or neutral. Everybody agrees that lethal mutations are disposed right away,but,for neutralists,in the fact that a new non-lethal mutation spreads or not in the population depends mostly on change. Even if these mutations are advantageous chance is the driving force. Keep in mind that neutral mutations aren't necessarily silent at the protein level and that they can also be mutations that slighly change a protein without altering its function. Of course,after these harmless but useless mutations are fixed,they can also find a niche and give some advantage to the individuals that carry them,later on.
Neutralism is a wery poverfull theory becouse it accounts very well for the way in which species build their adaptation potential before they need it.
If you are doing phylogeny,these neutral mutations are really the ones you're intrested in. You don't want to see adaptation;you want to measure evolutionary distances and the best measure of evolutionary distances you have is counting number of random and quasi-neutral events that occured on your sequences since they separated their ancestor. You can think of these mutations like each tick of a clock that been working,one mutation at time,for a million years."
Vastaukset 3
Vanhimmat
Eli usein kuulee kreaattien esittävän väitteitä tyyliin "informaatiota ei voi syntyä itsestään" ja "nykyaikainen informaatioteoria tukee kreationismia".
Mitä he tarkkaanottaen näillä väitteillään tarkoittavat, eli miten he määrittelevät informaation vaikkapa molekyylitasolla, miten sen määrää mitataan ja mikä teoria muka tukee heidän väitteitään.
En tiedä.
Tottapuhuen ihmettelten väitettä,jonka Leisola esitti skepsiksen huuhaapalkinnonjakoon lähettämässään viestissä.
Väitteen mukaanhan nykytiede ei huomioi informaatiota biologiassa.
Kuitenkin bioinformatiikka on kasvava tieteenala,ja sen tuottaman todisteet tukevat nimenomaan evoluutiota..
Dembskihän laskee todennäköisyyksinä,eli informaatio on sitten Dembskin mukaan epäsattumaa.
Eli "negentropiaa".
Dembski laskee todennäköisyydet suoraan,ei ota "vaihtoja" huomioon.
(Eli Dembski ei laskee pokeripelin värisuoran todennäköisyyden ja väittää sitten että värisuoraa ei voi saada edes miljoonalla korttien vaihdolla...)