Re: Speciation
Posted: Mon Aug 27, 2012 3:36 am
Excellent...but for some science already knows everything because they are using computers and their doctor can give them a pill to help with their flu.Jonathan.s wrote:'Speciation' is still a very vexed question in evolutionary biology. The problem is the absence of fossils that belong to the intermediary forms that the 'gradual change' model seems to require. One example is transitional forms between lizards and snakes, but there are many others.
It seems like even the #1 has been defined by science and this without philosophical references.
Which is surprising since nobody can actually provide us with this definition.
Still others grasp one aspect of a theory, which they do not grasp fully, and cling to it for dear life....like genetic drift.
We are now to believe that sexual attraction is irrelevant since it's all just dumb luck...which is another way of saying: I don't know.
See when you go to the casino you cannot calculate the forces acting upon the die, so you just call the outcome luck. It's a way of dealing with the Heisenberg Uncertainty Principle while retraining the illusion that you actually provided an explanation.
I remind you that the humanities, in general, suffer from the absence of what you call "hard science" and are fraught with psychological and social and cultural and political considerations.
This is why some opinions can be dismissed as "hateful" or motivated by personal failings whereas the more comforting ones suffer no such critique because they sooth the majority and no weakness is sought in their motive.
Furthermore, there is no strong will behind the explanations - the Darwinian ones in particular - as most researchers are dependent upon grants and may suffer irreparable personal damages to career and family if they dare ask certain questions.
And you think Gould, the liberal, is the last word in Evolution Theory?Jonathan.s wrote:This is one of the reasons why Stephen J Gould introduced his 'punctuated equilibrium' model.
Try Pinker.
Cladogenesis is a clever way of negating the long periods of genetic isolation which would explain the current diversity of human types. It is a way of saving the liberal ideal of uniform potentials across geographic lines. It's a way of dismissing recent history as being irrelevant or inconsequential...yet performances in all fields, no matter how many politically-correct twists they are given still conform to a more "hard Darwinian model"....some would call it a "cruel" one....others would try to slander it by accusing it of hate mongering and of having ulterior motives...but whatever.
Censorship is alive and well...and more sophisticated these days.
Some, around here, would have us believe that environment plays no part in evolution, really revolutionizing the field altogether - zero, zilch, nada.
Things just happen magically, I suppose...or they follow some divine path.
So, we are to believe that no evolution occurs for centuries, under changing environmental conditions and then suddenly everything changes in a sudden spurt?
Even so...what factors are necessary for a species to splinter-off into two different types?
Use your own words.
Thanks for the rundown...now have you herd of Epigenetics: Ghost in your Genes.Jonathan.s wrote:The ultra-Darwinists (Dawkins et al) are strongly wedded to the notion of incremental random changes, so they reject anything like 'laws of form' or underlying prototypes. Simon Conway Morris, a 'dissident biologist', offers a model of 'convergence' which says that nature generally tends to develop along predictable lines. He points out the fact that both visual organs and photosynthesis evolved a number of times via very different routes.
Here, not only is environment decisive but its impact is immediate.
The question - and this is supposedly a forum dedicated to personal insight - was how YOU understood evolution or how YOU think species splinter-off from a common ancestor.Jonathan.s wrote:What is interesting is that it is still controversial, and also that it is controversial for philosophical reasons. The ultra-Darwinists would love it if it were all a matter of hard science, but it appears far from the case.
I'm assuming you actually think that there are different species, (am i going to be accused of being a speciest now?) because a philosophical case can be made against that and science uses sex as its deciding factor.
If I wanted to hear from Gould I would read his book. I do not think much of Gould but neither to I casually dismiss him as some do anyone they consider "immoral".
This is the level thinking has fallen to and you are telling me what? That it's accidental, or too small to matter?
Are you people so afraid of expressing personal opinion that you cannot utter a single word without referring to an "authority" figure?
This is a philosophy forum.
Philosophy is not about discussing what other people thought about reality...that's academics. Philosophy is about discussing, debating, over what YOU think about reality, with all the authorities and influences and mentors and personal insights and experiences included.
Have you people become afraid to think because some douche-bag will intimidate you with threats based on morality?!!!
You, YOU, see diversity in all forms, right?
Is it an illusion? If not then...how does it come about?
Not even two twins are exactly alike and you, yourself, are not the same today as you were yesterday, no?
You do not only see large divergences outside what you would consider your "kind" but you also see it within the group you are supposed to consider your own kind.
The very concept of a human species is a vastly greater generalization than any racial or sexist could come up with.
You see it within your own family.
Some of this divergence results in something as fundamental as a level of consciousness that leads to world dominance, and we call this intelligence...or you can call it imagination if you wish.
How do you think intelligence develops to a higher degree in one branch of a common genetic tree when it does not in another?
Chance? Is that your final answer?
Even these sudden spurts of evolution require a triggering mechanism.
Let's get it started.
We have a population A, right?
Population A is a group of unknown origins and with undefined characteristics.
And we have population B.
-1-
How do we decide that popualtionA is other than popualtionB?
This is the preliminary step...empiricism.
The first step towards the scientific method.
How do we judge divergence?
What criteria, what medium, do we use to categorize and differentiate.
At this point I remind you that consciousness is a tool of discrimination, no matter if the word itself has fallen in made repute in our modern, politically-correct, dumbed-down, world.
To discriminate is to be aware of a divergence...this is its original and only meaning.
If you agree proceed...
-2-
Now, I would say that genetic isolation must occur if any differentiation can come about, no matter if it occurs in short spurts or incremental steps.
If not then all mutations become evenly distributed within the entire population if they offer an advantage. No chance here...all natural selection is guided by conscious judgments in higher life forms. Females, actually, play the role of genetic filters...later becoming mimetic filters. They are how detrimental mutations are weeded out of a population's genetic pool.
This genetic isolation can be geographical, originally, but later on and with the development of mimetic groupings it might take on the form of a social isolation.
If you agree proceed...
-3-
Whatever changes occur in populationA cannot spread to populationB and how fast or how slow these changes come about is a detail that need not enter the evaluation yet.
These changes are nothing more than mutations. Genetic mutations that either benefit the organism, burden it or are neutral in their effect.
Sexuality develops mechanism to select mutations. This is the only reason sex evolves...alter acquiring social and cultural and psychological roles.This, too, need not be addressed yet.
We'll assume that whatever triggers a mutation to become detrimental or beneficial is also factored into our evaluations as being part of the environment.
What is to be considered beneficial, fit, superior, is determined by the particularities of a given environment at a given time.
These mutations accumulate, in time adding a level of complexity to the entire process, as the combination of what attributes benefit the organism must outweigh those that burdens it within this given environment and since the environment is also evolving the standard of fitness is also altering, proportionally to the changes in the environment. A meteorite hit leading to a sudden Ice Age would be an accelerated environmental alteration leading to drastic changes in genetic balances.
These aggregate mutations are what become the behavioral and physical attributes of a population, of a species.
There is no mind/body dichotomy. If the environment affects the form it also affects the brain.
If you agree proceed...
Let us stop here before we go onto...
-4- specialization, particularly sexual specialization as in male/female; how it evolves, why it evolves...
-5- how long is enough for a sufficient divergence to occur so as to be called a different species...
-6- how and why genes are uniformly distributed...
-7-how and why particular population groups develop particular custom, traditions, ways of thinking and behaving which we might call rudimentary forms of culture...
-8-why the senses evolve and why some consider them tools of tricking the organism rather than tools for aiding the organism to survive. How the cultural ideal evolved making sensual perception superficial or erroneous.....
etc.