Why is natural selection not random?

[Grumpy]

Emil

The question is why within a species or races, individuals are not exactly the same. What is the mechanism and why these differences occur?

They are many and varied. Mutation produces DNA with changes, most of which are fatal or neutral, but a few give traits that give a reproductive advantage. In addition, DNA does not throw things it has found to work away, it keeps DNA for traits that may not be expressed until there is great stress on the genome or even the presence of certain predators or parasites, transcription errors can switch the places of sections of DNA, which may or may not affect survivability or cause disease or malformation and your DNA is mixed with other DNA, each having it's own mix of traits, sexual reproduction became so dominate BECAUSE of the mixing of different genes gives MORE variation for Natural Selection to test. A bacteria has much less variation(but much faster reproduction)because it's DNA is largely(but not completely)seperate from that of other bacteria.

Grumpy

 

[Aqueous Id]

Inharent sense can be there in all live beings. That may suggest directed selection.

What are you talking about?
I have no idea what this means.

 

[Aqueous Id]

So far I have come across atleast 12 different definitions of what natural selection is, different websites/books seem to be saying different things. It would help if you could define it, then we can discuss if it is random or not.

:bugeye:
I have no idea what you mean. How many different ways can it be defined? If you're getting different definitions, you're probably reading the wrong material. Books with titles like you cited above are obviously not interested in biology. You would obviously need to read biology to get the right answer.

When asking about science, it's best to pick an authoritative source.

Natural Selection: Differential survival and reproduction of organisms as a consequence of the characteristics of the environment.​

If your eyes get tired reading the thousands of journal articles that encompass natural selection, you can also turn to audiovisual lectures and talks, such as this presentation of selection in action.

Since it's a topic of science you can obviously find any number of universities or schools with teaching materials.

What's the issue? I don't get it.

And what's the issue about randomness?

:shrug:

Will the bird see the uncamouflaged mutant bug? Probably. Eventually. Most of the time.

What difference does randomness make for the bug? He's maladapted.

From that standpoint, the game of chance is over. Eventually his phenotype will die out.

What does "directed" mean? It has the ring of creationism in it.

Where's the controversy?

:shrug:

 

[Kumar]

What are you talking about?
I have no idea what this means.

My definition of natural selection somewhat resemble which other poster has told:-

"Natural Selection: Differential survival and reproduction of organisms as a consequence of the characteristics of the environment."

One Definition of natural is :based on inharent sense of right and wrong and when we use natural in natural selection, it should be selection based on inharent sense of right & wrong.

 

[wellwisher]

The environment sets potentials. There are certain cause and effect scenarios which will minimize the impact of the potential. Relative to natural selection, the potentials establish their own selective cause and effect relative to optimization.

Say you were near a campfire and the wind starts to swirl. There is a moving sweet spot where you will breath the least smoke and get the best air. If you walk randomly to the beat of your own drum, without regards to smoke direction being established by the wind, you will breath too much smoke. Natural selection is like a dance where the potentials are leading, not the DNA. The DNA will establish variety so there is the capacity to find the sweet spot.

If the weather turns bad due to global climate change, this sets a new range of potentials for life. If life can minimize the impact of these potentials, they will have selective advantage. The sweet spot will result in the least physical resources needed and the least wear and tear on the hardware.

 

[darryl]

I have no idea what you mean. How many different ways can it be defined?

Let's be honest yeh! Please see this thread alone, users have so far given multiple meanings for natural selection.

According to the following sources natural selection is:

The process whereby organisms better adapted to their environment tend to survive and produce more offspring. The theory of its action was first fully expounded by Charles Darwin and is now believed to be the main process that brings about evolution.

Google Dictionary

“survival of the fittest,” the principle that in nature those individuals best able to adapt to their environment will survive and reproduce, whereas those less able will die.

Medical dictionary

According to which organisms tend to produce progeny far above the means of subsistence; in the struggle for existence that ensues, only those progeny with favorable variations survive; the favorable variations accumulate through subsequent generations, and descendants diverge from their ancestor.

Parker, S. P. (Ed.). (1997). McGraw-Hill Dictionary of Bioscience. New York: McGraw-Hill.

survival: a natural process resulting in the evolution of organisms best adapted to the environment

http://wordnetweb.princeton.edu/perl/webwn?s=natural selection

Natural selection is the process by which traits become more or less common in a population due to consistent effects upon the survival or reproduction of their bearers. It is a key mechanism of evolution.

http://en.wikipedia.org/wiki/Natural_selection (old version)

Natural selection is the gradual, non-random, process by which biological traits become either more or less common in a population as a function of differential reproduction of their bearers. It is a key mechanism of evolution.

http://en.wikipedia.org/wiki/Natural_selection (new version)

Natural Selection: The main mechanism of evolutionary change. In a given population of organisms, there are heritable traits that enable some members to contribute a larger number of offspring than others. If these offspring also have a greater reproductive success, then the genetic composition of the population is altered, thus evolution.

http://www.oceanlink.info/glossary.html

The mechanism for evolutionary change in which environmental pressures cause certain genetic combinations in a population to become more abundant; genetic combinations best adapted for present environmental conditions tend to become predominant.

http://www.mhhe.com/biosci/pae/glossaryn.html

An evolutionary process where heritable traits that arise through mutation give an organism a higher chance of survival in their environment and become more common in a population as these organisms have a higher likelihood of reproducing.

http://www.sciencelearn.org.nz/About-this-site/Glossary/(namefilter)/n

The preservation of favorable alleles and the rejection of injurious ones.

http://www.ncbi.nlm.nih.gov/books/NBK21126/

The process described by Darwin's theory of evolution that favors certain genotypes and disfavors others. This process is entirely guided by the interaction of an organism with its environment.

www.whatislife.com/glossary.htm

Natural selection is the process in which some organisms live and reproduce and others die before reproducing.

http://www.enchantedlearning.com/subjects/dinosaurs/glossary/indexn.shtml

A principle of Darwins theory of evolution that animals that have adapted better to their envir onment allows some members of a species to produce more offspring that others, as a result of possessing advantageous traits that improve survival chances and increase reproductive success.

The natural filtering process by which individuals with higher fitness are more likely to reproduce than individuals with lower fitness.

mitpress.mit.edu/books/FLAOH/cbnhtml/glossary.html

The directional process of evolutionary change. Some genes or allelles become more common over time because of beneficial effects that they have on survival and reproduction.

web.missouri.edu/~flinnm/courses/mah/glossary.htm

Differential survival and reproduction among members of a population or species in nature; due to variation in the possession of adaptive genetic traits.

www.streamnet.org/glossary.html

The concept developed by Charles Darwin that genes which produce characteristics that are more favorable in a particular environment will be more abundant in the next generation.

http://www.csrees.usda.gov/nea/biotech/res/biotechnology_res_glossary.html

The process in nature by which, according to Darwin's theory of evolution, only the organisms best adapted to their environment tend to survive and transmit their genetic characteristics in increasing numbers to succeeding generations while those less adapted tend to be eliminated.

American Heritage Dictionary

The process by which organisms that are better suited to their environment than others produce more offspring.

http://science.yourdictionary.com/natural-selection

a natural process resulting in the evolution of organisms best adapted to the environment

http://dictionary.kids.net.au/word/natural_selection

Natural selection is the theory that only the strong survive.

http://www.vocabulary.com/dictionary/natural selection

a process resulting in the survival of those individuals from a population of animals or plants that are best adapted to the prevailing environmental conditions. The survivors tend to produce more offspring than those less well adapted, so that the characteristics of the population change over time, thus accounting for the process of evolution

http://www.collinsdictionary.com/dictionary/english/natural-selection

The process by which genetic traits are passed on to each successive generation. Over time, natural selection helps species become better adapted to their environment. Also known as “survival of the fittest,” natural selection is the driving force behind the process of evolution.

National Geographic Glossary

Evolutionary change based on the differential reproductive success of individuals within a species

Michael A.Park, Introducing Anthropology: An Integrated Approach, 2nd Ed., glossary

Pretty much all DIFFERENT answers!

 

[Neverfly]

They pretty much all say the same thing, except for the definition supplied by vocabulary dot com which was just stupid and inaccurate.

 

[spidergoat]

darryl,

It's not that complex. Random "selection" would imply that individuals die randomly, that their reproductive success is random.

But we know that survival and reproduction rates are not random, but depend to a huge degree on the fitness or individual traits of the living thing. As long as your DNA code affects your fitness and ability to survive, it will influence whether you live or die to a larger or smaller degree. So, this means that non-fit DNA code will be weeded out of the gene pool as those less-fit individuals die sooner. Thus, evolution!

 

[Neverfly]

Fitness is a relative term.
Very relative.

Fitness could be whether or not you strike a good first impression with a breed-able female, regardless of faulty genes. If the genes are so faulty that associated health problems begin to affect individuals prior to breeding age, that species faces extinction. What happens after that is well... fair game.
Clearly, we're not exactly built to last...

Does the Banana Slug look especially fit to anyone? How about that Octopus? I don't care what any of you say- that's prime breeding material right thar!!

Fitness can be defined for Evolution as : Good enough to not go extinct, given that the environment doesn't change drastically.

Fitness as strength only comes into play when discussing competition for resources.
A desert shows many fit animals, but a small amount of diversity.

A rainforest shows extreme diversity- with animals that wouldn't last very long if they were placed elsewhere.

Transplanted animals can wreak havoc on an eco-system in competition.
Obviously, rats are more fit than the Dodo. Or is it that humans are more fit than the Dodo?
Odd considering that the Dodo was an ancient creature.

And then you have blind cave salamanders. How did being blind make them strong and fit?
Well, it didn't. But lacking eyes in total darkness is an advantage, as the soft and susceptible eyes can very easily be injured in the dark leading to lethal infection. Plus, anxious females can't see if you have eyes or not. They'll still do a mutant that has no eyes. The genes are introduced by that breeding and show a slight advantage over the salamanders with sensitive little eyeballs in the dark. Sure the process takes a very long time, but as long as they keep successfully breeding--- They are FIT.
http://www.youtube.com/watch?v=Kkm8x6Zp-14&feature=related


Charles Darwin never said, "Survival of the Fittest."
Someone else did. I can't remember who, because he was not important. All I know is someone with a time machine needs to go back in time and bitch slap him.

Q:What did one set of genes say to the other set? A:"Like, Oh my God, you are so, like, random!"

 

[darryl]

darryl,

It's not that complex. Random "selection" would imply that individuals die randomly, that their reproductive success is random.

But we know that survival and reproduction rates are not random, but depend to a huge degree on the fitness or individual traits of the living thing. As long as your DNA code affects your fitness and ability to survive, it will influence whether you live or die to a larger or smaller degree. So, this means that non-fit DNA code will be weeded out of the gene pool as those less-fit individuals die sooner. Thus, evolution!

This website presents an example of natural selection:

http://evolution.berkeley.edu/evolibrary/article/evo_25

Yet does not even define natural selection or explain what it exactly is!

According to their other page:

http://evolution.berkeley.edu/evolibrary/article/evo_32

Natural selection is the simple result of variation, differential reproduction, and heredity — it is mindless and mechanistic. It has no goals; it's not striving to produce "progress" or a balanced ecosystem.

So natural selection is mindless, mechanistic and has no goals but it is still not random ?

 

[darryl]

Charles Darwin never said, "Survival of the Fittest."
Someone else did. I can't remember who, because he was not important. All I know is someone with a time machine needs to go back in time and bitch slap him.

Darwin took "Survival of the fittest" off Herbert Spencer. In 1872 in the last edition of his book The Origin of Species he came to the conclusion that "natural selection" and "survival of the fittest" were the same thing. Chapter 4 of his book was titled "Natural Selection, or the Survival of the Fittest" in this chapter Darwin wrote that "survival of the fittest" is a "more accurate" definition of natural selection.

Natural selection is the process in which some organisms live and reproduce and others die before reproducing.

So natural selection is not random becuase organisms choose who they reproduce with whilst others die before reproducing. :shrug: Doesnt explain anything about evolution.

 

[Neverfly]

Clue me in here but who claimed it is not random... and the word "Random" needs to be defined for this context.

Random mutations, in this context, applies. It is "random." At least from our perspective.

Selective breeding is based on what traits a potential mate likes or dislikes. That is not random in this context.
If the traits are flawed enough that organisms have difficulty surviving to breeding age, that can be termed in this context as random, due to random mutations and events.

Ask yourself: Is it difficult to understand or are you resistant to understanding it?

Mazulu has a preference that he's able to tie in spiritual beliefs to science.

I will be very blunt- even some biologists and atheists may not like this statement- but it's how it is:
Evolution and Spiritual beliefs/Creation cannot be reconciled.
They stand apart. They cannot agree. It's just the way it is.

If a person cannot stand to leave them unreconciled, they are left with removing God to being active at the time of the Big Bang and inactive after that- or deliberately creating a clever, billions of years deception of making it look like he's not in existence while sending prophets to claim that he is in questionable desert scribblings.
Both notions are too insane to bother with trying to accept for a rational person.

 

[darryl]

Clue me in here but who claimed it is not random... and the word "Random" needs to be defined for this context.

It says so on most websites

http://www.pbs.org/wgbh/evolution/library/faq/cat01.html

Evolution is not a random process. The genetic variation on which natural selection acts may occur randomly, but natural selection itself is not random at all. The survival and reproductive success of an individual is directly related to the ways its inherited traits function in the context of its local environment. Whether or not an individual survives and reproduces depends on whether it has genes that produce traits that are well adapted to its environment.

I am still not getting why natural selection is not random.

Random mutations, in this context, applies. It is "random." At least from our perspective.

If mutations are random like most scientists claim they are, then why isn't natural selection as well?

I will be very blunt- even some biologists and atheists may not like this statement- but it's how it is: Evolution and Spiritual beliefs/Creation cannot be reconciled.

That is offtopic slightly for this thread, but note how natural selection was invented by a creationist.

 

[Neverfly]

If mutations are random like most scientists claim they are, then why isn't natural selection as well?

Why would it need to be? Evolution has randomness, but think about this:
There's randomness in your daily life. How much of what happens to you is due to random events (Flat tire) and how much by choice?
Just because one part is random doesn't mean all must be. Just because some is not random doesn't mean all cannot be.

 

[darryl]

The following was written by Richard William Nelson:

Richard Dawkins has written that natural selection is not random.

Jerry Fodor and Massimo Piattelli-Palmarini, in their new book entitled What Darwin Got Wrong, delivers a stunning exposé on the Dawkins’s inane assertion that 1) natural selection is a logical theory, and 2) natural selection is nonrandom.

Seasoned by decades of scientific investigation, Fodor and Piattelli-Palmarini begin by demonstrating that even “Darwin’s theory of natural selection is fatally flawed”. Not only flawed, they view the concept of natural selection is simply an “intensional fallacy”.

Fodor and Piattelli-Palmarini are not lone critics. With over 20 pages of references, the authors demonstrate that the theory of natural selection is no more than circular reasoning: a tautology.

Fodor and Piattelli-Palmarini explains: “[T]here is at the heart of adaptations theories of evolution, a confusion between (1) the claim that evolution is a process in which creatures with adaptive traits are selected and (2) the claim that evolution is a process in which creatures are selected for their adaptive traits… Darwinism is committed to inferring (2) from (1)”. Fodor and Piattelli-Palmarini conclude, “We think this argument, although ubiquitous in the literature, is fallacious.”

Fodor and Piattelli-Palmarini also address Dawkins’ issue of “nonrandom survival”, by pointing out that nonrandom processes require a mechanism to overcome entropy—randomness. The obvious question is – what is the mechanism that natural selection uses to overcome nature’s tendency towards randomness?

To answer this question, Fodor and Piattelli-Palmarini quotes from Gabriel Dover (2006), the British geneticist that coined the term “molecular drive”: “Selection is not a process as such with predictable outcomes based on fixed, selective ‘powers’ of individual genes controlling aspects of phenotype.”

The evidence demonstrates that natural selection does not deliver “predictable outcomes”. Lack of evidence for a predictable outcome, highlights the fact that natural selection does not have an operational mechanism to overcome randomness to increase complexity—the essence of evolution.

Despite over 150 years of investigation since the publication of The Origin of Species, no known natural law has been discovered to guarantee natural selection as a nonrandom process. Currently, there are no known natural mechanisms to overcome the general tendency of all nature towards randomness without an intervention. Contrary to Dawkins’ assertion, natural selection is simply a random process.

What is the role of natural selection, then? For Fodor and Piattelli-Palmarini, “We think of natural selection as tuning the piano, not composing the melody.” This is not the nonrandom force of evolution as championed by Dawkins.

Fodor and Piattelli-Palmarini, like Richard Dawkins, are evolutionists and “out-right, card-carrying, sign-up, dye-in-the-wool, no-holds barred atheists.” On the subject of natural selection acting as a nonrandom agency, however, the contrasts could not be more acute.

Consensus that natural selection cannot possibly be a nonrandom process has reached a tipping point. Mutations are random. Natural selection is random. Dawkins contention of “nonrandom survival of randomly varying hereditary instructions” is now clearly emerging as simply “breathtaking inanity.”

 

[Grumpy]

darryl

If mutations are random like most scientists claim they are, then why isn't natural selection as well?

Is the result of moving the handle of a car jack random? No. Even if every movement of the jack handle is completely random, the only movements that have any effect are the one's that cause the jack to go up a notch(not random).

In evolution the random motions of the handle are the variations in the traits(from mutations and other causes), they are random. But the only variations that survive are those that give the lifeform a competitive advantage to reproduce, all the other variations dissappear from the gene pool. Even slight competitive advantages insure that those genes become more prevalent in the gene pool. That's Natural Selection and it is not random.

So natural selection is not random becuase organisms choose who they reproduce with whilst others die before reproducing. Doesnt explain anything about evolution.

Sometimes sexual selection(choosing who to mate with)occurs, but it often leads to evolutionary cul-de-sacs like the Peacock, primed to be removed from competition sooner rather than later. But this is a result of intellectual evolution and behavior which, much like selective breeding by man, uses the evolutionary mechanisms toward self selected goals(pretty and otherwise useless tail feathers). Intellect can override or direct evolution but that is not the "Natural Selection" we are talking about here.

So natural selection is mindless, mechanistic and has no goals but it is still not random ?

Yes.

That is offtopic slightly for this thread, but note how natural selection was invented by a creationist.

Darwin was actually studying for the clergy, but it seems mainly because he could work indoors with no heavy lifting involved and continue his scientific investigations. But whatever he believed before his trip on the Beagle, what he found convinced him otherwise. If you make the same investigation honestly, with an open mind, you can come to no other conclusion than that Evolution has occurred throughout the history of life on Earth. Creatures that existed one hundred million years ago no longer exist, creatures alive today did not exist then(OK, there were sharks and aligators, but no monkeys). And Natural Selection is what drives evolution, often by hundreds or thousands or even millions of creatures dying for every one that survives to reproduce. Natural Selection is driven by nothing but survival to reproduce, whether you survive is determined by how well the traits that your DNA gives you meet the conditions you find yourself in. If you survive to reproduce you have been "Naturally Selected", if you don't, you are dirt(or food for other creatures).

Grumpy

 

[spidergoat]

This website presents an example of natural selection:...

So natural selection is mindless, mechanistic and has no goals but it is still not random ?

Natural selection describes how the circumstances of nature combine with the fitness of the individual or the gene(s) and results in variable survival rates. Perhaps the birds with the larger beaks are able to project their DNA forward in time because the larger beak allows them to take advantage of a particular food source. So, the DNA that results in large beaks becomes more frequent in the gene pool, and it can be said that the species changes just that small degree. The accumulation of these small changes results in what we call evolution.

 

[Aqueous Id]

Let's be honest yeh! Please see this thread alone, users have so far given multiple meanings for natural selection.
Pretty much all DIFFERENT answers!

Yeah, let's be honest about what different means.

So, according to you if each authority does not use a formulaic phrase that matches verbatim what every other authority uses then they are different.

That's the honesty of propaganda. Obviously, just like learning and understanding science, learning and understanding language requires a slight degree of sophistication. In this case, let's assume a high-school level.

Each and every one of your frenetically searched sources is saying the same thing. If you can't see that then maybe you need help in Science and English.

All you are doing is manufacturing a controversy which does not exist, simply by using tactics of propaganda. If you were attempting to argue from a position of evidence, then you would simply bring the evidence and the conversation would be about evidence, which is the larger goal of the forum, at least as far as it serves as a platform of mutual edification and as a myth-buster.

However in this case, I would have to say: "busted".

 

[Aqueous Id]

This website presents an example of natural selection:

http://evolution.berkeley.edu/evolibrary/article/evo_25

Yet does not even define natural selection or explain what it exactly is!

You see the bird eating the green bug? It was selected by its color and eaten so it will not reproduce. I chose this specifically for you since you have a problem with words.

So natural selection is mindless, mechanistic and has no goals but it is still not random ?

The green bug was eaten because it was noticed by its color. What does any of what you just said have to do with that?

 

[Aqueous Id]

The following was written by Richard William Nelson:
Richard Dawkins has written that natural selection is not random.

So?

Jerry Fodor and Massimo Piattelli-Palmarini, in their new book entitled What Darwin Got Wrong, delivers a stunning exposé on the Dawkins’s inane assertion that 1) natural selection is a logical theory, and 2) natural selection is nonrandom.

Yes and a raft of experts have also condemned Jerry Fodor and Massimo Piattelli-Palmarini as I mentioned before.

So far you have people in philosophy, behavioral science and pharmacology. Do you think there's a reason why no biologists are represented here? As you trot out your argument from a position of authority, keep in mind that you are still evading the central issue which is evidence. Words and ideas are easily distorted. Evidence speaks for itself. The bird eats the visible bug. Now all you need to do is show that the bird eats randomly and we can move on.