Still waiting for that "observed" example or at least a definition of what you mean by observed.
The one Coyote gave suffices. We observe that humans and chimps no longer interbreed. We also observe that humans and chimps share genetic markers that can only be explained by common ancestry. The differences between the human and chimp genome are consistent with the accumulation of mutations that are filtered through selection. So we have microevolution (mutation and selection) giving rise to macroevolution (separate species).
Yes....I will say this: The pursuit of a definition for macroevolution is a waste of my time.
We have often found that creationists do not have a definition for macroevolution, so it is not surprising that you do not have one either. This is why creationist protestations are so hollow. When they claim that macroevolution is impossible what they are actually saying is that it is impossible for anyone to present evidence that creationists would accept as macroevolution. That is why creationists can not give a definition for macroevolution because once they do they know that we can present evidence that demonstrates macroevolution.
Actually creationists do have a definition of macro-evolution. Macro evolution is evolution that produces an organism that is of a different kind than the created kind of its ancestors.
When asked for a working definition for kind we get the same answer: there is none. As soon as they create a working definition of kind then they know that we can present a transitional species that bridges the gap between those kinds.
A lot of time has passed since I started this thread, and I've learned a lot in the process ... from Introduction to Evolution (work in progress)
I have often found that human languages offer a good analogy for comparing microevolution and macroevolution. Like all analogies, languages aren't a perfect corollary, but they can make the subject a bit more accessible to the layperson.
Latin was the official language of the Roman Empire, and after the Empire's collapse their native tongue gave birth to many regional languages that we call the Romance languages. In fact, we can trace their lineages:
One could say that they evolved, although not in the biological sense. So how does this process of language evolution work, and how does it relate to micro and macro evolution?
First, you have populations that tend to talk amongst each other, but not as much to their neighbors. This results in regional dialects. These are small changes from one generation to the next. This is analogous to microevoution. Each generation is still able to talk to the generation before and after it, but there are still small changes. Over time those changes add up so that people separate by centuries may not have understood one another even though they were a part of the same language population. I remember trying to read Chaucer's works in the original Middle English, and it was quite difficult to say the least. There was never a time where a single French generation was born that could not communicate with their parents. However, there is no guarantee that a French generation could have communicated easily with someone 10 generations before them.
So we have populations where small changes are continually happening. We also need to remember that we have more than one population which causes DIFFERENT changes to occur in each population. If these populations are separated for a time and then meet again they aren't able to understand one another, even though their common ancestors spoke the same language. This is macroevolution, and it is driven by micro changes in each language that happen over time. Even though French and Italian speakers came from a common ancestral population that spoke a common tongue, now they can't easily understand one another in their native tongue.
Biological evolution works in a similar fashion. Small numbers of mutations occur in each generation which doesn't produce a lot of differences between generations, and still allows fo interfertility between members of the same population. However, over many generations those small changes add up so that individuals separated by millions of years can look quite different from each other in the same way that Middle English and Modern English are quite different. This is macroevolution.
Also, if two populations split off from one another and don't interbreed, then different mutations will accumulate in each population. Over time this will result in two contemporaneous populations that are different from one another even though they share a common ancestral population. That is macroevolution, and it occurs by the accumulation of changes caused by microevolution.
The changes that have occurred in the Indo-European language family, for example, demonstrate that languages follow a ‘downhill’ simplification in inflections, etc. by natural processes. Adam Smith commented on this in one of his books.
That would be the fallacy of analogy. Just because languages simplify over time does not mean that genomes must also.
Similarly observed evolution seems to follow a downhill path with loss of information so, using Durston's definitions, macroevolution is rare or nonexistent.
How does Durston determine that there is a loss in information, and how does Durston determine when macroevolution has occurred?
Macroevolution: genetic change that requires a statistically significant increase in functional information.
Then I can point to an example of macroevolution. We can find mutations in pocket mice that produced an increase in functional information. This gain of function mutation allows mice to have black fur:
"Both alleles of the entire Mc1r gene (954 bp) were sequenced in the 69 mice in Fig. 1. Twenty-four single-nucleotide polymorphisms were observed: 15 were synonymous and 9 were nonsynonymous. Four of the nine amino acid polymorphisms were observed only in the dark mice from the Pinacate locality (Arg-18 ¡ú Cys, Arg-109 ¡ú Trp, Arg-160 ¡ú Trp, and Gln-233 ¡ú His). These four amino acid variants were present at high frequency (82%) among the Pinacate dark mice and were in complete linkage disequilibrium with one another. All other Mc1r amino acid polymorphisms were present at low frequencies and showed no association with mouse color. "
"Third, the dark allele is dominant over the light allele, consistent with observations of Mc1r mutations in the mouse (11, 16) and other organisms (21¨C25). In the laboratory mouse, loss-of-function mutations at Mc1r are recessive and result in light color, whereas gain-of-function alleles are dominant and result in dark color (16). All heterozygous mice observed at the Pinacate site are dark with unbanded hairs and are phenotypically similar to the homozygous dark mice. " http://www.pnas.org/content/100/9/5268.full
Possibly; at least in the Pinacate population since different results were obtained in the Armendaris population.
The phenotypic results were the same in the form of a dominant allele for dark fur color. As the previous post states, a dominant black allele for coat color is a gain in function.
I'm not sure how they define gain-of-function mutations except as they relate to colour. This is not necessarily the same as a gain of functional information. A broken switch can result in a light that is always on or always off, but the switch is still broken.
A mutation that changes gene expression is a gain in functional information.
I would bet $100 dollars that if the switch were on all of the time and then a mutation caused the switch to turn off and on, you would call that a loss in functional information as well. Am I wrong? It would seem that no matter what change is made you will call it a loss in functional information. If a fish evolves limbs you will call that a loss in information because it no longer has fins.
Be honest, there is no evidence that you will ever accept as a gain in functional information.
Since "This difference is controlled in large part by the interaction of two proteins, the melanocortin-1-receptor (MC1R) and the agouti-signaling protein" the mutations could prevent normal interaction of this system; the equivalent to a broken switch.
And there we have it. If a fish evolved limbs from fins, you would claim that it is equivalent to a broken switch because it is normal for the fish to have fins. You classify all changes as broken switches simply because they are a change.
Remember that beneficial is not the same as an increase in functional information.
Then evolution doesn't need to produce functional information in order to produce macroevolution as you define it. If we started with the earliest vertebrate and watched ever generation from that ancestor to modern humans you would classify the whole thing as a continual loss of information simply because the organisms change.
A comparison could be with Nylonase which has been shown to be a fine tuning of an existing enzyme that already had some action on nylon, and this is acknowledged to be within the capability of the mutation-selection mechanism. As Douglas Axe said Darwinism is a good tinkerer but a poor innovator.
Yet another invocation of "fine tuning" to get out of admitting there was a gain in functional information. "Fine tuning" is just a nonsense word you have made up.
btw, I take it then that you have accepted Durston's definitions for micro and macro evolution.
As we have already seen, you have already stopped using those definitions.
Defective means no longer performing the original function, nor an improved one".
The problem is that you define any change as a defect no matter how beneficial that change is. Once again, you would label every single evolutionary change from the first vertebrate ancestor to modern humans as a continual loss in function simply because the organisms didn't do what they used to do.
Elsewhere I have suggested that Durston's definitions might be used.
As soon as I demonstrated an increase in functional information you rejected that definition.
From the Uncommon Descent definition:
Macroevolution, in all its possible meanings, implies the emergence of new complex functions.
I think you, I, and everyone else would agree that the differences between humans and chimps equates to macroevolution. I would hazard a guess that you do not accept humans and chimps descending from a common ancestor.
So what complex functions separate humans and chimps? If you can't answer that question, then it would seem this definition doesn't work either.
However as far as I can tell from the article the record starts with forams and ends with forams.
Now you are using the creationist name game. This is where you claim it is microevolution if you can use the same word to group two species.
So let's see how that works out for you. Humans and apes evolving from a common ancestor would be microevolution because they are all still within Hominidae. Humans, bears, and echidnas evolving from a common ancestor would be microevolution because they started out as mammals and ended up as mammals. Those are just varieties of mammal species. Humans, frogs, and fish evolving from a common ancestor is also microevolution because the common ancestor was a vertebrate, and all the modern species are still vertebrates.
See a problem here?
Since there are known hybrids between Linnaean species and genera it does not fit well the Biological Species concept based on the ability to produce viable offspring.
The biological species concept allows for hybrids, so it isn't a problem.
microevolution = changes in gene frequencies and trait distributions that occur within populations and species macroevolution = large evolutionary change, usually in morphology, typically refers to evolution of differences among populations that would warrant their plaecment in different genera or higher-level taxa
To use an analogy, walking to the curb is microwalking and walking to the store is macrowalking. It seems that there is an arbitrary line between micro and macro.
The trouble I have with this is following the path of lineage, we have a breeding population that becomes a variety, then it becomes a species when the varieties are reproductively isolated, then it becomes a genus after daughter populations go through the variety\species category transition, and it becomes a family as the descendants continue to evolve varieties and species and genera ... etc etc etc ...
Saying that macroevolution is the production of a new genus only shifts the problem to how we determine if two species belong to separate genera. As it turns out, that is entirely arbitrary. We could put humans and all other apes into the same genus tomorrow if we so choose. In fact, some scientists have argued for putting chimps and humans in the same genus (Homo troglodytes). We could put all primates in the same genus if we wanted to since everything outside of species is a human construct. There are thousands of species in the Drosophila genus, so numbers aren't a problem. In fact, there may even be more genetic diversity in the Drosophila genus than there is in the Primate order (may be worth a look). From a quick scan of the literature, the Drosophila genus has been evolving for 40 million years which is comparable to the evolution of the order Primate.