Consideringlily, Oncedeceived and defining evolution

[Xeriar]

Recently there was a thread regarding a bit of a challenge between two members here, about who had a better grasp of evolutionary principals.

Consideringlily and Oncedeceived were asked to give a brief definition of evolution and its components, and after this post I post their 'papers' as they were PMed to me, word for word.

I'm not going to call this a contest - there's no poll and that would lead to little constructive work anyway. I will see about commenting on each later this week.

 

[Xeriar]

I'd like to thank Xeriar for assisting us in this.







Evolution is the theory that all life forms have evolved from one common ancestor. Evolution changes properties in populations of organisms that extend past the life- time of one individual. The changes are through inheritable genetic exchange from one generation to the next. Decent through modification presents this full diversity of life forms, as we know it.

There are two scales of evolution, microevolution and macroevolution. Microevolution is a change within a population of organisms. There are mechanisms that account for microevolution such as natural selection, genetic drift, mutations and migration. The same mechanisms are at work with macroevolution but on a larger scale throughout the entire history of life. This history includes the very first life form and which comes under the heading of abiogenesis a distinct study outside of the ToE. Macroevolution takes that first life form and follows all the branches from it to all life forms in what is called the tree of life. The tree of life demonstrates all changes, lineages and diversification within history.

The mechanism Natural selection is sometimes considered the driving force of evolution. Its concept is historically based on survival of the fittest. The organisms most capable of existing in any given environment and living to reproduce will have offspring to carry on their genes. Natural selection is the process by which the organisms with the best or most favorable genetic adaptations out-compete other organisms in a population, tending to displace the less-adapted organisms. This process derives logically from the concepts of survival of the fittest and differential reproduction. If you have variation, differential reproduction, and heredity you will have evolution by natural selection.

Genetic Drift is the mechanism of chance. It refers to changes in allele frequencies of a gene pool due to chance. Genetic drift occurs in both large and small populations; large populations suffer less sampling error. Genetic drift causes isolated gene pools to become dissimilar; some alleles are lost and others are fixed. There are no apparent advantages in changes by genetic drift.

Mutations are changes in DNA sequences of a gene. Mutations in a gene’s DNA sequence can alter the amino acid sequence of the protein encoded by the gene. Like words in a sentence, the DNA sequence of each gene determines the amino acid sequence for the protein it encodes.

Migration occurs when a population enters another population and changes the gene pool.

Coevolution happens when two or more species influence each other's evolution. It is most often invoked to explain co adaptations between species. This happens in plant insect combinations frequently. Insects and plants influence each other's evolution, by the evolution of insecticides in plants and of detoxification and avoidance mechanisms in insects. It has been argued that the evolutionary relations between insects and plants less often take the form of coevolution than of sequential evolution, in which plant evolution influences insect evolution but not vice versa.

One cannot present evolution without discussing species. A concept that defines a species as members of populations that actually or potentially interbreed in nature, not according to similarity of appearance. Although appearance is helpful in identifying species, it does not define species. Speciation is a lineage-splitting event that produces two or more separate species or the transformation of one species into a new species over time; speciation is the final result of changes in gene pool allele and genotypic frequencies. As evolution progresses, gene flow is eventually stopped between one population and the species as a whole. As a population undergoes changes in gene frequencies it could diverge entirely until it is reproductively distinct from other populations of the species from which it diverged. This is called phyletic evolution or anagenesis. Alternatively the population could evolve into two distinct species that exist at the same time. This is called true speciation or cladogenesis. Speciation involves the genetic change in a subgroup of a population that makes the new population unable to reproduce offspring with the original population. If a reproductive barrier occurs because of isolation by a physical barrier, the isolated population can evolve and develop into a new species. A term called allopatric speciation. Speciation can also occur when a subpopulation migrates into a new niche which is called parapatric speciation. However, speciation might also happen in a population with no specific extrinsic barrier to gene flow. Sympatric speciation occurs when a subpopulation that occupies the same niche as the remainder of the species develops a unique mutation that prevents it from mating with the original population. That new species may also have an advantage which allows its establishment as a species in the same niche.

 

[Xeriar]

For my opening argument, I want to be concise and accessible to people, who do not live and breathe this debate. I’m not going to cut and paste pages of other people’s writing. Instead, I will give a brief overview of some of the foundational concepts of evolution.

That said I will answer Dantose’s question. They are as good a place as any to start.

According the ToE:
What is a species?
What is evolution?
What are the main methods of genetic change in a population? (please provide a brief description of each method)
Can the theory of evolution apply to non-living systems as well?


1. What is a species? First the term (like all words) species itself is meant to symbolize the phenomena we see in nature. Words help us to discuss and better understand nature but they are not the phenomena themselves. Terms are only as good as our knowledge of the phenomena. Science recognizes the limitations of our ability to understand things and hones our understanding by subjecting knowledge to the process of the Scientific Method.

Species is the most basic unit used to classify organisms. The term is generally meant to signify members of a natural breeding population who choose to interbreed and share genetic information due to recent common ancestry. Often members of a species share common physical characteristics due to sexual selection and exposure to the same environmental selectors. However, physical appearance is not the key-determining factor in classifying a species. DNA analysis is the best way to determine members of a species.

The sub species of Canus lupus familiaris illustrate the malleability of physical features within one species.



Despite the superficial differences, domestic dogs have not diverged enough to be considered a separate species than Canus lupus or the Gray wolf.

Speciation, the verb form of the word, is the driving force of evolution. All evolutionary changes occur at the species level.

2. What is evolution?
I borrowed this from the Berkeley site because it pretty much sums up what I believe evolution encompasses.

Biological evolution, simply put, is descent with modification. This definition encompasses small-scale evolution (changes in gene frequency in a population from one generation to the next) and large-scale evolution (the descent of different species from a common ancestor over many generations).
http://evolution.berkeley.edu/evolibrary/article/0_0_0/evo_02

I am going to pick up this question at this point as well:

Can the theory of evolution apply to non-living systems as well?

To be more specific evolution always involves living things. Without the ability to self-replicate, genes cannot be passed on and change over time. The only exceptions I can think of are viruses, which are not technically considered living.

3. What are the main methods of genetic change in a population? (please provide a brief description of each method)

Briefly, the main methods of genetic change in a population are mutation, migration (gene flow), genetic drift, and natural selection.

All of these forces work to shape a breeding population’s evolution. Mutation is caused by a copying error during the replication of DNA. Most of the time these changes are harmless or neutral. Even a seemingly neutral mutation like the extra folds of skin around a bloodhound’s nose can sometimes have a beneficial effect and increase an organism’s ability to secure food and live longer and produce more offspring. Most mutations have no noticeable effect. Bad mutations are not uncommon, but if they decrease the ability of an organism to survive and breed, they are naturally removed from the breeding population. Like the same dog with soft palette deformities, in the wild this animal would be less likely to breed.

Migration or gene flow happens when new genes are introduced to a breeding population through breeding. Members of the same species still have some genetic variation as evidenced by dog breeds. For example, if a wild dog were to be separated from its own pack and join another pack. If the dog for example, were faster than the other dogs, the genes would likely spread through the new pack by breeding.

Genetic drift shapes evolution by minute changes to genes over time. For example, horse populations and donkey populations were separated in the wild for a long enough time that their DNA doesn’t match up perfectly. The result is sterile offspring or the mule. These natural barriers to breeding are the reason there are billions of species living and extinct rather than one species.

Lastly, there is natural selection. Natural selection is the process whereby; traits that aid survivability in a particular environment are preserved in a population. Natural selection does not guarantee survival. Environments are subject to change. Climate changes can turn tropical ecosystems into deserts. Species either adapt to change or become extinct.

 

[Lilandra]

Thanks Xeriar. I'm off to bed. I will comment tomorrow.

 

[Oncedeceived]

Thanks, me too.

 

[mark kennedy]

According the ToE:
What is a species?

Generally considered two seperate populations that can no longer interbreed that could have at one time. There are exceptions like the chimpanzee and bonobo but species is not clearly defined scientifically. The criteria for taxonomic catagories tend to be highly subjective and assigned largely for the sake of organizing charts.

What is evolution?

The change of alleles in populations over time.

What are the main methods of genetic change in a population? (please provide a brief description of each method)

(Courtesy of NCI Cancer Genome Anatomy Project site)

SNP Animation

99.9% of one individual DNA sequences will be identical to that of another person. Of the 0.1% difference, over 80% will be single nucleotide polymorphisms (SNPs).

Eventually, SNP profiles that are characteristic of a variety of diseases will be established. Then, it will only be a matter of time before physicians can screen individuals for susceptibility to a disease just by analyzing their DNA samples for specific SNP patterns.​

SNP and Genotyping Overview

Can the theory of evolution apply to non-living systems as well?

No, there is no theory of evolution outside of Biology. It is often used as an expression but does not represent a culmination of tested hypothesis resulting in a valid theory.

Now back to your regularly scheduled discussion.

 

[Lilandra]

Evolution is the theory that all life forms have evolved from one common ancestor. Evolution changes properties in populations of organisms that extend past the life- time of one individual. The changes are through inheritable genetic exchange from one generation to the next. Decent through modification presents this full diversity of life forms, as we know it.

Is this just an explanation of the accepted definition of evolution or is single common ancestry of all "life forms" your opinion on what evolution is as well?

There are two scales of evolution, microevolution and macroevolution. Microevolution is a change within a population of organisms. There are mechanisms that account for microevolution such as natural selection, genetic drift, mutations and migration. The same mechanisms are at work with macroevolution but on a larger scale throughout the entire history of life.

Both microevolution and macrevolution are terms that are used by Creationists to differentiate between speciation and evolution over several speciation events. All changes happen at the species level.

This history includes the very first life form and which comes under the heading of abiogenesis a distinct study outside of the ToE.

So then you agree abiogenesis is not included in evolution?

Macroevolution takes that first life form and follows all the branches from it to all life forms in what is called the tree of life. The tree of life demonstrates all changes, lineages and diversification within history.

Why do you distinguish between microevolution and macroevolution?

The terms speciation and common ancestry are far more descriptive.

The mechanism Natural selection is sometimes considered the driving force of evolution.

Its concept is historically based on survival of the fittest. The organisms most capable of existing in any given environment and living to reproduce will have offspring to carry on their genes. Natural selection is the process by which the organisms with the best or most favorable genetic adaptations out-compete other organisms in a population, tending to displace the less-adapted organisms.

Less adapted? Is a dinosaur less adapted than a mammal?

This process derives logically from the concepts of survival of the fittest and differential reproduction. If you have variation, differential reproduction, and heredity you will have evolution by natural selection.

Differential Reproduction or Differential Reproductive Success?

I am not aware of an organism capable of differential reproduction. I can't even picture it.

Genetic Drift is the mechanism of chance. It refers to changes in allele frequencies of a gene pool due to chance. Genetic drift occurs in both large and small populations; large populations suffer less sampling error. Genetic drift causes isolated gene pools to become dissimilar; some alleles are lost and others are fixed.

Okay. But what is this next statement about?

There are no apparent advantages in changes by genetic drift.

Is this your opinion or do you have a source for this assertion?

 

[Lilandra]

Generally considered two seperate populations that can no longer interbreed that could have at one time. There are exceptions like the chimpanzee and bonobo but species is not clearly defined scientifically. The criteria for taxonomic catagories tend to be highly subjective and assigned largely for the sake of organizing charts.

Okay, chimps and bonobos like many other seperate species are capable of producing viable offspring.

The key distinction is that they choose not to breed in nature. Therefore they don't have that much of an effect on each other's seperate gene pools.

This aspect of defining species is not subjective, it is for practical reasons.

 

[Oncedeceived]

Is this just an explanation of the accepted definition of evolution or is single common ancestry of all "life forms" your opinion on what evolution is as well?

This is an explanation of the ToE.

Both microevolution and macrevolution are terms that are used by Creationists to differentiate between speciation and evolution over several speciation events. All changes happen at the species level.

Microevolution and macroevolution are terms that were given to the scales of evolution by Scientists.

From: http://www.talkorigins.org/faqs/macroevolution.html#concept

The history of the concept of macroevolution

How did the terms enter into scientific use, and what has happened to them since?
In the "modern synthesis" of neo-Darwinism, which developed in the period from 1930 to 1950 with the reconciliation of evolution by natural selection and modern genetics, macroevolution is thought to be the combined effects of microevolutionary processes.
The terms macroevolution and microevolution were first coined in 1927 by the Russian entomologist Iuri'i Filipchenko (or Philipchenko, depending on the transliteration), in his German-language work Variabilität und Variation, which was an early attempt to reconcile Mendelian genetics and evolution. Filipchenko was an evolutionist, but as he wrote during the period when Mendelism seemed to have made Darwinism redundant, the so-called "eclipse of Darwinism" (Bowler 1983), he was not a Darwinian, but an orthogeneticist (he believed evolution had a direction). Moreover, Russian biologists of the period had a history of rejecting Darwin's Malthusian mechanism of evolution by competition (Todes 1989).
In Dobzhansky's founding work of the Modern Synthesis, Genetics and the Origin of Species, he began by saying that "we are compelled at the present level of knowledge reluctantly to put a sign of equality between the mechanisms of macro- and microevolution" (1937: 12), thereby introducing the terms into the English-speaking biological community (Alexandrov 1994). Dobzhansky had been Filipchenko's student and regarded him as his mentor. In science as in all academic disciplines, it is difficult to deny a major tenet of one's teachers due to filial loyalty, and Dobzhansky, who effectively started the modern Darwinian synthesis with this book, found it disagreeable to have to deny his teacher's views (Burian 1994).
The term fell into limited disfavour when it was taken over by such writers as the geneticist Richard Goldschmidt (1940) and the paleontologist Otto Schindewolf to describe their orthogenetic theories. As a result, apart from Dobzhansky, Bernhardt Rensch and Ernst Mayr, very few neo-Darwinian writers used the term, preferring instead to talk of evolution as changes in allele frequencies without mention of the level of the changes (above species level or below). Those who did were generally working within the continental European traditions (as Dobzhansky, Mayr, Rensch, Goldschmidt, and Schindewolf are) and those who didn't were generally working within the Anglo-American tradition (such as John Maynard Smith and Richard Dawkins). Hence, use of the term "macroevolution" is sometimes wrongly used as a litmus test of whether the writer is "properly" neo-Darwinian or not (Eldredge 1995: 126-127).
The term was revived by a number of mainly paleontological authors such as Steven Stanley (1979), Stephen Jay Gould and Niles Eldredge, the authors of punctuated equilibrium theory (see Eldredge 1995), who argued that something other than within-species processes are causing macroevolution, although they disavow the view that evolution is progressive. Many paleontologists have held that what happens in evolution beyond the species level is due to processes that operate beyond the level of populations – for example, the notion of species selection (the idea that species themselves get selected similarly to the way alleles get selected within populations, see Grantham 1995, Rice 1995, and Stidd and Wade 1995 for reviews and discussions).
The idea that the origin of higher taxa such as genera requires something special is often based on the misunderstanding of the way in which new lineages arise. The two species that are the origin of canine and feline lineages probably differed very little from their common ancestral species and each other. But once they were taxonomically isolated from each other, they evolved more and more differences that they shared internally but that other lineages didn't. This is true of all lineages back to the first eukaryotic (nuclear) cell. Even the changes in the Cambrian explosion are of this kind, although some (e.g., Gould 1989) think that the genomes (gene structures) of these early animals were not as tightly regulated as modern animals, and therefore had more freedom to change.

So then you agree abiogenesis is not included in evolution?

Abiogenesis is not considered to be part of evolution. Evolution begins with the first life form and does not include how that life form came about. Evolution is a study of living organisms, not as abiogenesis which is non-life to life.

Why do you distinguish between microevolution and macroevolution?

The terms speciation and common ancestry are far more descriptive.

We are discussing the definitions of ToE and those are the terms that were specified for the scales of evolutionary processes. I

You do not understand this comment?

Less adapted? Is a dinosaur less adapted than a mammal?

Yes and no. When dinosaurs ruled the day they were more successful than the early mammals. They dominated the environment and the mammals were regulated to a small animal existence due to natural selection until the dino's went extinct. The mammals then moved into the new niches provided by the dino distruction. So the smaller mammals were more "adapted" to the smaller role and being smaller in size were not affected as much when the extinction event occurred.

Differential Reproduction or Differential Reproductive Success?

Differential reproduction whether reproduction proceeds with lesser or greater success is central to the process of natural selection; it determines whether a given mutation becomes established in the general population. Due to this natural selection, together with successful differential reproduction, causes the characteristics of a species gradually to change when adaptive (i.e. beneficial) mutations sweep through the population. In this way, differential reproduction allows one species to gradually evolve into a new species. This is the process of evolution.

I am not aware of an organism capable of differential reproduction. I can't even picture it.

I've got to go to work I'll finish this later. Sorry.

There are no apparent advantages in changes by genetic drift.

Is this your opinion or do you have a source for this assertion?

I have a source:

Evolutionary change within a population consists of a change in the proportions (frequencies) of alleles in the population. For example, the proportion of a rare allele may increase so that it completely replaces the formerly common allele. Changes in the proportions of alleles can be due to either of two processes whereby some individuals leave more descendants than others, and therefore bequeath more genes to subsequent generations. One such process, genetic drift, results from random variation in the survival and reproduction of different genotypes. In genetic drift, the frequencies of alleles fluctuate by pure chance. Eventually, one allele will replace the others (i.e., it will be fixed in the population). Genetic drift is most important when the alleles of a gene are neutral—that is, when they do not substantially differ in their effects on survival or reproduction—and it proceeds faster, the smaller the population is. Genetic drift results in evolutionary change, but not in adaptation.

http://evonet.sdsc.edu/evoscisociety/what_is_evolution.htm

Finished.

 

[Lilandra]

This is an explanation of the ToE.

I go by the accepted definition. My cards are on the table. If your personal opinion is different than single common ancestry, please post it. It is impossible to discuss evolution if I am not aware of your position.

I'll wait to discuss the rest until you are finished posting it.

Microevolution and macroevolution are terms that were given to the scales of evolution by Scientists.

From: http://www.talkorigins.org/faqs/macroevolution.html#concept

The history of the concept of macroevolution

How did the terms enter into scientific use, and what has happened to them since?
In the "modern synthesis" of neo-Darwinism, which developed in the period from 1930 to 1950 with the reconciliation of evolution by natural selection and modern genetics, macroevolution is thought to be the combined effects of microevolutionary processes.
The terms macroevolution and microevolution were first coined in 1927 by the Russian entomologist Iuri'i Filipchenko (or Philipchenko, depending on the transliteration), in his German-language work Variabilität und Variation, which was an early attempt to reconcile Mendelian genetics and evolution. Filipchenko was an evolutionist, but as he wrote during the period when Mendelism seemed to have made Darwinism redundant, the so-called "eclipse of Darwinism" (Bowler 1983), he was not a Darwinian, but an orthogeneticist (he believed evolution had a direction). Moreover, Russian biologists of the period had a history of rejecting Darwin's Malthusian mechanism of evolution by competition (Todes 1989).
In Dobzhansky's founding work of the Modern Synthesis, Genetics and the Origin of Species, he began by saying that "we are compelled at the present level of knowledge reluctantly to put a sign of equality between the mechanisms of macro- and microevolution" (1937: 12), thereby introducing the terms into the English-speaking biological community (Alexandrov 1994). Dobzhansky had been Filipchenko's student and regarded him as his mentor. In science as in all academic disciplines, it is difficult to deny a major tenet of one's teachers due to filial loyalty, and Dobzhansky, who effectively started the modern Darwinian synthesis with this book, found it disagreeable to have to deny his teacher's views (Burian 1994).
The term fell into limited disfavour when it was taken over by such writers as the geneticist Richard Goldschmidt (1940) and the paleontologist Otto Schindewolf to describe their orthogenetic theories. As a result, apart from Dobzhansky, Bernhardt Rensch and Ernst Mayr, very few neo-Darwinian writers used the term, preferring instead to talk of evolution as changes in allele frequencies without mention of the level of the changes (above species level or below). Those who did were generally working within the continental European traditions (as Dobzhansky, Mayr, Rensch, Goldschmidt, and Schindewolf are) and those who didn't were generally working within the Anglo-American tradition (such as John Maynard Smith and Richard Dawkins). Hence, use of the term "macroevolution" is sometimes wrongly used as a litmus test of whether the writer is "properly" neo-Darwinian or not (Eldredge 1995: 126-127).
The term was revived by a number of mainly paleontological authors such as Steven Stanley (1979), Stephen Jay Gould and Niles Eldredge, the authors of punctuated equilibrium theory (see Eldredge 1995), who argued that something other than within-species processes are causing macroevolution, although they disavow the view that evolution is progressive. Many paleontologists have held that what happens in evolution beyond the species level is due to processes that operate beyond the level of populations – for example, the notion of species selection (the idea that species themselves get selected similarly to the way alleles get selected within populations, see Grantham 1995, Rice 1995, and Stidd and Wade 1995 for reviews and discussions).
The idea that the origin of higher taxa such as genera requires something special is often based on the misunderstanding of the way in which new lineages arise. The two species that are the origin of canine and feline lineages probably differed very little from their common ancestral species and each other. But once they were taxonomically isolated from each other, they evolved more and more differences that they shared internally but that other lineages didn't. This is true of all lineages back to the first eukaryotic (nuclear) cell. Even the changes in the Cambrian explosion are of this kind, although some (e.g., Gould 1989) think that the genomes (gene structures) of these early animals were not as tightly regulated as modern animals, and therefore had more freedom to change.




Abiogenesis is not considered to be part of evolution. Evolution begins with the first life form and does not include how that life form came about. Evolution is a study of living organisms, not as abiogenesis which is non-life to life.




We are discussing the definitions of ToE and those are the terms that were specified for the scales of evolutionary processes. I





You do not understand this comment?




Yes and no. When dinosaurs ruled the day they were more successful than the early mammals. They dominated the environment and the mammals were regulated to a small animal existence due to natural selection until the dino's went extinct. The mammals then moved into the new niches provided by the dino distruction. So the smaller mammals were more "adapted" to the smaller role and being smaller in size were not affected as much when the extinction event occurred.



Differential reproduction whether reproduction proceeds with lesser or greater success is central to the process of natural selection; it determines whether a given mutation becomes established in the general population. Due to this natural selection, together with successful differential reproduction, causes the characteristics of a species gradually to change when adaptive (i.e. beneficial) mutations sweep through the population. In this way, differential reproduction allows one species to gradually evolve into a new species. This is the process of evolution.




I've got to go to work I'll finish this later. Sorry.

[/quote]

 

[Oncedeceived]

My post is finished.

 

[Pesto]

Speciation, the verb form of the word, is the driving force of evolution. All evolutionary changes occur at the species level.

I would disagree with this. As Mark Kennedy pointed out, evolution is change in allele frequency from one generation to another. For example, if you look at lactose intollerance, it has decreased in populations that rely on dairy. This is evolution below the species level.

Can the theory of evolution apply to non-living systems as well?

To be more specific evolution always involves living things. Without the ability to self-replicate, genes cannot be passed on and change over time. The only exceptions I can think of are viruses, which are not technically considered living.

Really, something doesn't have to be alive in the traditional sense in order to evolve. It just has to meet these criteria.

1. It replicates
2. It has heritable traits
3. The replication process is imperfect.

Self replicating robots would evolve, assuming they were completely autonomous.

 

[Lilandra]

I would disagree with this. As Mark Kennedy pointed out, evolution is change in allele frequency from one generation to another. For example, if you look at lactose intollerance, it has decreased in populations that rely on dairy. This is evolution below the species level.

Really are there humans below the species of Homo sapiens?

Increased lactose tolerance in some populations is happening at the species (Homo sapiens) level.

Really, something doesn't have to be alive in the traditional sense in order to evolve. It just has to meet these criteria.

1. It replicates
2. It has heritable traits
3. The replication process is imperfect.

Self replicating robots would evolve, assuming they were completely autonomous.

We are talking about biological evolution.

 

[Exhausted]

We are talking about biological evolution.

You seem to be implying quite the opposite in the post he quoted.

 

[Oncedeceived]

I would disagree with this. As Mark Kennedy pointed out, evolution is change in allele frequency from one generation to another. For example, if you look at lactose intollerance, it has decreased in populations that rely on dairy. This is evolution below the species level.


Really, something doesn't have to be alive in the traditional sense in order to evolve. It just has to meet these criteria.

1. It replicates
2. It has heritable traits
3. The replication process is imperfect.

Self replicating robots would evolve, assuming they were completely autonomous.

I agree, language is evolutionary. Society evolves in some ways I think.

By the way, Xeriar did not post what you responded to but Consideringlily.

 

[Lilandra]

This is an explanation of the ToE.

Like I said earlier, my cards on are the table. My opinion of the origin of biodiversity is explained by the accepted definition of evolution

If your opinion isn't universal common ancestry, then please post it. It is an unfair advantage for you to know my position and for me to guess at yours.

Microevolution and macroevolution are terms that were given to the scales of evolution by Scientists.

From the start, Darwin argued that there is no difference between the 2 terms.

Darwin, on the other hand, saw no fundamental difference between microevolution and macroevolution. He asserted that "Certainly no clear line of demarcation has as yet been drawn between species and sub-species — that is, the forms which in the opinion of some naturalists come very near to, but do not quite arrive at, the rank of species: or, again, between subspecies and well-marked varieties, or between lesser varieties and individual differences. These differences blend into each other by an insensible series; and a series impresses the mind with the idea of an actual passage." (Darwin, 77)

In other words, macroevolution is simply several series of microevolution over several speciation events.

The mechanisms of evolution operate at the species level.

A reptile doesn't become a mammal in one speciation event. There is no Voila!

A species of reptile experiences minute changes that blend over several species into the next. Sometimes the changes are relatively rapid if new niches are vacant.

Macroevolution as simply compiled microevolution is accepted to this day.

With the discovery of the structure of DNA and genes, genetic mutation gained acceptance as the mechanism of variance in the 1960s. This developing theory of evolution was then called the modern evolutionary synthesis, which remains prominent today. The synthetic model of evolution equated microevolution and macroevolution, asserting that the only difference between them was one of time and scale.

I look at it this way. The terms speciation and common ancestry are more decriptive of the phenomena they are describing than micro and macroevolution.

We are discussing the definitions of ToE and those are the terms that were specified for the scales of evolutionary processes.

http://en.wikipedia.org/wiki/Macroevolution

The term macroevolution implies there is some sort of active process to account for something like different families of taxa. The only part of the process where evolution is active is in the seperate species between these taxa.

Macroevolution is simply the big picture or common ancestry.

Yes and no. When dinosaurs ruled the day they were more successful than the early mammals. They dominated the environment and the mammals were regulated to a small animal existence due to natural selection until the dino's went extinct. The mammals then moved into the new niches provided by the dino distruction. So the smaller mammals were more "adapted" to the smaller role and being smaller in size were not affected as much when the extinction event occurred.

All animals have undergone a great deal of adaption. The only thing that changes is environment.

Differential reproduction whether reproduction proceeds with lesser or greater success is central to the process of natural selection; it determines whether a given mutation becomes established in the general population. Due to this natural selection, together with successful differential reproduction, causes the characteristics of a species gradually to change when adaptive (i.e. beneficial) mutations sweep through the population. In this way, differential reproduction allows one species to gradually evolve into a new species. This is the process of evolution

Differential reproduction is not an evolutionary process or term. Concede your error and move on. I knew what you meant (Differential Reproductive Success) but it is not what you said.

There are no apparent advantages in changes by genetic drift. I have a source:

Evolutionary change within a population consists of a change in the proportions (frequencies) of alleles in the population. For example, the proportion of a rare allele may increase so that it completely replaces the formerly common allele. Changes in the proportions of alleles can be due to either of two processes whereby some individuals leave more descendants than others, and therefore bequeath more genes to subsequent generations. One such process, genetic drift, results from random variation in the survival and reproduction of different genotypes. In genetic drift, the frequencies of alleles fluctuate by pure chance. Eventually, one allele will replace the others (i.e., it will be fixed in the population). Genetic drift is most important when the alleles of a gene are neutral—that is, when they do not substantially differ in their effects on survival or reproduction—and it proceeds faster, the smaller the population is. Genetic drift results in evolutionary change, but not in adaptation.

How does what you quoted say that there are no apparent advantages to genetic drift?

 

[Lilandra]

You seem to be implying quite the opposite in the post he quoted.

No, I wasn't. i simply pointed out a possible exception. I did not imply that non-living evolution is some sort of rule within the TOE.

 

[Oncedeceived]

Like I said earlier, my cards on are the table. My opinion of the origin of biodiversity is explained by the accepted definition of evolution

If your opinion isn't universal common ancestry, then please post it. It is an unfair advantage for you to know my position and for me to guess at yours.

My cards are out there as well. Our positions are irrelavent. This thread is not to discuss opinion. It is to provide our understanding of ToE. Opinion has nothing to do with knowledge of a subject. I don't see where anyone has an advantage over the other when the whole exercise was to determine whether or not I understood ToE. If you will remember:

Quote by Oncedeceived:
I would venture a guess that I understand evolution as much or more than you do by what has been discussed by us both on this forum.

by Lily:

Talk is cheap.I can demonstrate I know more about evolution than you judging from your posts thus far.

In the thread you are talking about, I had to explain to you what falsification means.

However, if you feel that you can demonstrate you know more about evolution than I do, we can start a thread. We can have a poll that says judging from this thread who knows more about evolution lily or OD.

From the start, Darwin argued that there is no difference between the 2 terms.

I really don't understand your aversion to the terms microevolution/macroevolution. It seems to me that you are wanting to change "terms" to fit your comfort level as you have accused me.
Remember:

Quote by Lily: My experience with her is you can take her step by step through the evolutionary process and she will redefine terms rather than concede a point.

Example,evolution will be at term to limited to her comfort level. Point blank questions outside of her comfort level like did humans evolve from other apes will spur evasive manuevers but never a straight forward answer.

If you state Creationists are dishonest, she will redefine Creationists to all Christians including TEs. As if TEs are typical of the group when they are not.

In other words, macroevolution is simply several series of microevolution over several speciation events.

The mechanisms of evolution operate at the species level.

I never implied anything else.

A reptile doesn't become a mammal in one speciation event. There is no Voila!

Please provide where I have implied this. I never claimed any such thing. I have simply supplied my knowledge on the subject and you are creating arguments that I have not presented.

A species of reptile experiences minute changes that blend over several species into the next. Sometimes the changes are relatively rapid if new niches are vacant.

Macroevolution as simply compiled microevolution is accepted to this day.

I never said otherwise.

I look at it this way. The terms speciation and common ancestry are more decriptive of the phenomena they are describing than micro and macroevolution.

If you feel more comfortable with those terms I don't mind using them.

http://en.wikipedia.org/wiki/Macroevolution

The term macroevolution implies there is some sort of active process to account for something like different families of taxa. The only part of the process where evolution is active is in the seperate species between these taxa.

Macroevolution is simply the big picture or common ancestry.

Like I said, if you feel more comfortable using those terms I have no problem with that.

All animals have undergone a great deal of adaption. The only thing that changes is environment.

I don't follow? What are you saying is wrong with my explanation on Dino/mammal adaptation? I said that the Dinosaurs dominated the environment and that the mammals were relegated to a niche that kept them relatively small in that environment. I also specified that when the extinction event occurred why the mammals moved into the newly acquired niche. So please let me know where I am mistaken.

Differential reproduction is not an evolutionary process or term. Concede your error and move on. I knew what you meant (Differential Reproductive Success) but it is not what you said.

So Differential reproductive Success is an evolutionary term?

How does what you quoted say that there are no apparent advantages to genetic drift?

My mistake, I was thinking that you asked about adaptation.

I meant that the changes are not apparently advantageous or disadvantageous for that matter.

 

[Lilandra]

My cards are out there as well.

Your position on evolution is not posted in this thread, mine is.

Our positions are irrelavent. This thread is not to discuss opinion. It is to provide our understanding of ToE.

Our positions are not irrelevant. Even were you to agree that my definitions were correct according to science, if you have an issue with those definitions, that implies your understanding of the origin of biodiversity is different.

Besides, if you are aware of the nuances of evolution according to science, there must be a logical or evidentiary reason, that you have reservations about it.

Opinion has nothing to do with knowledge of a subject. I don't see where anyone has an advantage over the other when the whole exercise was to determine whether or not I understood ToE.

Science is not about subscribing to a popular definition without a reason. If you have valid reasons why you do not subscribe to a theory completely, I think that it would be a simple matter to post them and support them.

If you will remember:
I really don't understand your aversion to the terms microevolution/macroevolution. It seems to me that you are wanting to change "terms" to fit your comfort level as you have accused me.
Remember:

I have posted quotes from Darwin and modern thought on these terms. it is not an unsupported opinion or simply my own "aversion".

I never implied anything else.
Please provide where I have implied this. I never claimed any such thing. I have simply supplied my knowledge on the subject and you are creating arguments that I have not presented.
I never said otherwise.

My point is macroevolution implies there is a large scale evolutiunary mechanism like with "microevolution" or speciation.

If you feel more comfortable with those terms I don't mind using them.

Like I said, if you feel more comfortable using those terms I have no problem with that.

I just feel they are more specific and descriptive.

I don't follow? What are you saying is wrong with my explanation on Dino/mammal adaptation? I said that the Dinosaurs dominated the environment and that the mammals were relegated to a niche that kept them relatively small in that environment. I also specified that when the extinction event occurred why the mammals moved into the newly acquired niche. So please let me know where I am mistaken.

You said an animal is "less adapted".

So Differential reproductive Success is an evolutionary term?

Bingo.

My mistake, I was thinking that you asked about adaptation.

I meant that the changes are not apparently advantageous or disadvantageous for that matter.

noted

 

[Oncedeceived]

Your position on evolution is not posted in this thread, mine is.

Our position is not necessary. Once again, we are providing evidence of our knowledge of evolution.

Our positions are not irrelevant. Even were you to agree that my definitions were correct according to science, if you have an issue with those definitions, that implies your understanding of the origin of biodiversity is different.

As long as I have knowledge of the scientific theory it doesn't matter. My understanding in this thread is only significant in regard to my understanding of the scientific theory of evolution. If I have issues with it, matters not. Scientists (in life sciences) for example understand evolution and its mechanisms and yet still have differing opinions on data sometimes.

Besides, if you are aware of the nuances of evolution according to science, there must be a logical or evidentiary reason, that you have reservations about it.

Yet this is not important to our discussion here. What is important is whether I am providing a truthful and knowledgible account of ToE.

Science is not about subscribing to a popular definition. If you have valid reasons why you do not subscribe to a theory completely, I think that it would be a simple matter to post them.

Why would I? That is not the issue. You felt that I did not have a scientific understanding of ToE. That is the issue and you continue to avoid it.

I have posted quotes from Darwin and modern thought on these terms. it is not an unsupported opinion or simply my own "aversion".

And I have provided ample verification that the terms are equally scientific and common.

My point is macroevolution implies there is a large scale evolutiunary mechanism like with "microevolution" or speciation.

So was mine.

I just feel they are more specific and descriptive.

Uh, yes you have said that.

You said an animal is "less adapted".

Quote:By me

Its concept is historically based on survival of the fittest. The organisms most capable of existing in any given environment and living to reproduce will have offspring to carry on their genes. Natural selection is the process by which the organisms with the best or most favorable genetic adaptations out-compete other organisms in a population, tending to displace the less-adapted organisms.

by you.

Less adapted? Is a dinosaur less adapted than a mammal?

As you can see I said that the best or most favorable genetic adaptations out compete other organisms which means they are less favorably adapted.

Bingo.

Fine I can accept that.

I would like a response to this please:

Quote by you:

A reptile doesn't become a mammal in one speciation event. There is no Voila!

My response:

Please provide where I have implied this. I never claimed any such thing. I have simply supplied my knowledge on the subject and you are creating arguments that I have not presented.