In all of those cases, selection is not random with respect to fitness.
I have never denied that evolution is a combination of chance and contingency. What I denied is that it is chance all the way through.
Fitness is random. It amounts tot he same thing. Evolution doesnāt have any preferred direction.
Goodā¦ finally some progressā¦ just so we are clear. What exactly do you mean by contingency?
Experiments demonstrate otherwise. Bacteria with mutations conferring antibiotic resistance quickly outnumber bacteria without those mutations in environments that contain antibiotics.
I mean the effect a mutation has on fitness in a specific environment, and the effect this fitness has on how the mutation is spread to future generations.
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Yes, in such environment, fitness is defined by resistance to antibioticsā¦ when the environment changes, (for example, a different antibiotic is used) fitness parameters change. Fitness changes according to the environment (including predators) and the environment changes randomly.
This is purely random and unpredictableā¦I.e dependent on chance.
So nothing wrong in saying the entire process is dependent on chance.
So this gets exactly to a key point.
The environment is not totally random. It is determined by features in a larger system than is modeled directly in biology. However, changes in the environment seems like random variable because we are not modeling that larger system. That does not mean it actually is random.
Keep in mind that when we talk about random and chance, that these are relative terms that depend on perspective. They are subjective terms @Ashwin_s.
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In most cases we are not sure what are the features of the environment, especially as we go back in time.
In such cases, contingency is assumed.
Contingency just means: the external factors that has an impact that we are not directly modeling. It is a catch all term that includes a whole range of things that we are just not directly dealing with from a certain point of view.
For example, the rise of mammals is contingent on the asteroid that fell 65 million years ago. From the biological point of view, this was just a random event that is not accounted for in biology. No theory of evolution makes predictions about when asteroids hit reset and free up a bunch niches. That does not mean weāve assumed the asteroid is totally random, or is epicurean chance, or is law like or is violating the laws of physics. We could even suppose an intelligent force wanted to create room for the mammals to rise, and tossed that asteroid our direction. That asteroid is contingency, from the point of view of biology.
So there is no āassumptionā. Contingency can include artificial selection too, and the input of intelligent design, but we cannot parse out what is what in that bucket without directly studying it.
This is significant data. I now understand your thinking.
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Correct, fitness is not random with respect to the environment. It is not chance all the way through as you tried to describe it earlier.
Need we go back to the example of the antibiotic resistant bacteria?
It would seem that communication on the part of scientists is not the problem here. It seems that you just donāt want to hear what they are saying.
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This is a giant quibble when you are participating on a list filled with folks who are buffeted by all sorts of disputes surrounding the term ārandomā. As far as Iām concernedā¦ any time (and I mean EVERY time ) you include the word random (without qualifying what you mean) you are intentionally sending out a point of confusion.
You canāt be lazy about explaining the word random! I think you will find that while you are here that leaving that word out of every post you make will not do your writing any harm at all.
While insisting to use the term just sends the wrong message!
The environment is randomā¦ you can call it contingency if it makes you happy. But itās still chance. Unless you believe the environment changes were guided to achieve a set goal.
Itās precisely because if contingency that fitness cannot be predicted except in cases like antibiotic resistance. I donāt see why you refuse to see the full consequences of your claim.
Nobody disputes small changes like antibiotic resistance. Itās the big picture at the macro evolution level that is being questioned.
Why so you want to deny the dependence on chance?
Itās not just the asteroid. The placenta is thought to have been developed as a result of a ERVā¦ that also would have to be contingent wouldnāt it? And pretty much every beneficial ārandomā mutation that turned up at the right time in the right place?
This is the first time I have heard of anyone claiming contingency need not be pure āepicureanā chance. Doesnāt science assume it is exactly that ? Just as it assumes that beneficial mutations were not directed by any purpose?
No, science does not assume that. Perhaps atheism does, but not science. There is nothing in science that tells about divine teleology (purpose). It is silent on matters of God.
That is not what contingency means. The fact that we have the specific syncytin we do at the location we have it is part of the historical contingency of the current moment. Other mammal families have different syncytins, in different locations, that perform essentially the same function. That difference is because of a different history.
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I have read claims that the word random (w.r.t mutations and events such as the meteor mentioned by you) means the following -
- Due to unknown causes.
- Not having any purpose or direction.
If definition 2 is valid. Then its directly speaks about purpose (whether Divine or of any other variety). How can you claim that science does not make claims connected to purpose?
Remember science is from a human point of view. The way to qualify #2 correclty is that one definition of random is not having any objectively discernable purpose.
Isnāt that a philosophical statement.By that definition, the entire process of evolution is randomā¦ and individual lives are also randomā¦ because we cant identify objectively discernable purpose for any natural processsā¦ ultimately for anything else.
This is a philosophical classification. What is materialistic philosophy doing in science???
Its very difficult to think that āevolutionary Scienceā does not have any commitment to materialism as a philosophy. It exists most comfortably in that particular world view.
That is not true.
Why notā¦ If randomness is due to not being able to identify an āobjectively discernableā purpose. Then randomness is decided by the limitations of the scientific method. So in a sense the limitations of the scientific method is being projected on mutations and the adjective ārandomā is ascribed to mutations (there is no reason mutations themselves should qualitatively differ based on presence or absence of purpose).
So obviously randomness will be projected on anything science studies which involves things that are not objectively discernableā¦ so scientifically speaking everything ultimately involves random causesā¦
Edit: This is why theories like evolution make philosophical claims in addition to scientific claimsā¦ atleast they do, when they are communicated to the public.
Why wouldnāt God have control over the environment. I am convinced that the dino-killing asteroid was completely Godās idea.
A good Philosophy of Science makes for good science. They are inextricably linked. In fact, the emergence of a sound philosophy is what helped turn Alchemy into Chemistry as we know it today!