KnightWhoSaysNi

Topic: Is there a distinction between micro and macro evolution?

A thread for the formal debate between Malachi256 and faust has been opened in FDD. This thread has been opened for discussion and commentary on that debate.

Jason

RufusAtticus

Hmmm, this will be an interesting debate because there is a distinction between macroevolution and microevolution; although, it's just an artifact of our human perception.

Principia

I don't get the point of this topic at all. So what if there is a distinction between microevolution and macroevolution?? This topic is begging for a definitions game, which is just what Creatos are looking for.

pz

No, there is a distinction, and it's real.

Shall we have the actual debate in here, and let the FD forum play peanut gallery?

Although I also agree with Principia; someone who doesn't believe macroevolution occurs and tries to argue that the distinction is real is playing an unproductive definitions game.

tribalbeeyatch

I'm really curious to see the first post in this debate. The micro/macro disctinction seems defensible given that it is drawn at the right point. But macro has already been demonstrated using that particular set of definitions, and so it becomes a case of winning the battle but losing the war. If the distinction is drawn elsewhere, though, then it is one drawn only by degree. Is a distinction of degree even worth arguing for? I suppose that it might be if you are YEC and think that time is too limiting for macro. But then shouldn't the age of the earth be argued first? If Malachi256 is as reasonable as he appears so far and follows through with this debate and an age of the earth debate, then I predict that the equilibrium of his worldview is about to be punctuated, so to speak.

faust

I won't be posting to the peanut gallery at all during the debate, out of fairness.
But a word towards the worth of this debate before this thread takes off into the stratosphere, carefully read my last post in the setup forum. The subject implies a slightly different focus than what my position is, and the reasons for it.

Enjoy!

ooh_child

THIS is why I decided to register on IIDB, and I'm greatly anticipating this debate. I have been lurking for awhile, but when I saw the subject thread deveoping I had to join the fun.
The PG should have fun with this!

MHB

Toto

That first post was, um, strange. Malachai doesn't really think there is a difference between micro and macro evolution, but since he starts with the assumption that the world is only 6000 yrs old, he concludes that there hasn't been enough time for micro evolutionary changes to have produced the diversity we see in front of us.

Or am I missing something?

tribalbeeyatch

That you managed to extract even that point is somewhat amazing. It sounds almost as if Malachi intends this a debate on the pedagogical utility of breaking evolution up into more easily digested units, with no defense of a micro/macro distinction on biological grounds whatsoever. If we're right and Malachi doesn't propose any biological barrier between micro and macro, then maybe they should postpone this topic and argue the age of the earth question first.

pz

Let's get a little fire going in here and start roasting the debaters. First on the barbecue...


Reading Malachi256's round of the debate, I'd have to give him an "F" so far. Even though I agree that there is a valid difference between micro and macro evolution, he starts off with some bad definitions and completely fails to support them logically.

Here's the definition of macroevolution:
This is basically a morphological definition of macroevolution. It doesn't work. Since there is no correspondence between the magnitude of a genetic change and the magnitude of the phenotypic result -- a point mutation can potentially have a greater effect than a large deletion -- this definition includes just about any mutation you can think of. All it has to do is generate a useful novelty.

This really doesn't fit any definition in the literature that I know of. It's extremely poor.


Here's the definition of microevolution:
This is another slightly peculiar definition. It's closer to the usual textbook definition, although there's a couple of oddities. One is that "pre-existent" clause -- are mutations excluded from his definition of microevolution? Another is the incorporation of speciation, which is usually considered a macroevolutionary phenomenon.

What really makes these two definitions completely useless, though, is that they aren't even using the same scale, so you can't use them to distinguish whether something is microevolutionary or macroevolutionary. An individual could have a mutation that generates a morphological novelty, which then spreads by microevolutionary processes through a population. It's both micro and macro, and he has just argued for the other side, and abolished any useful distinction!

His examples don't help, either. Evolution of feathers is macroevolution, while radiation of the cichlids, with the accompanying multiple speciation events and dramatic changes in morphology (look into cichlid pharyngeal/feeding adaptations -- it's radical) is microevolution. That's ridiculous.

Actually, the only way to separate these two is whether a new mutation is present or not. New mutation=macroevolution. Existing allele=microevolution. Again, this is nonsense -- population genetics and microevolutionary theory incorporate mutation as part of the process. If this were actually the criterion for distinguishing the two, I'd have to agree that there is no distinction.

The last part of his response should be some kind of justification for his definitions. It isn't.

Note that the question being debated is, "Is there a distinction between micro and macro evolution?" Suddenly, though, Malachi256 asks a completely different question: "So how do these definitions allow more accurate discussion and teaching of evolution?"

I guess we're not going to get any useful discussion of his most non-standard definitions. Instead, we get two arguments from consequences: 'if they were true, these definitions would be good because...'. Yeah, and if that dollar bill in my pocket were worth a billion dollars, I could throw a really big party.

His first rationalization for making a distinction between micro and macro is that it basically allows creationists deniability. It lets them categorize the science that has been done into 'microevolution', and pretend that there is no evidence for macroevolution. Aside from the fact that we don't typically mangle our definitions to the convenience of creationists (or evolutionists), this just isn't true. There is very solid evidence for the processes he has lumped into his definition of macroevolution.

His second reason is that it allows him to make operational teaching distinctions. He groups classes that are taught in typical universities into a "macroevolution" category (Comparative Anatomy, Embryology, Paleontology), a "microevolution" category (Hardy-Weinberg(? I presume this would be genetics and ecology)) and a hybrid category (bioinformatics). I don't understand the point, or in the case of bioinformatics, the rationale. These are different disciplines, with biases in one direction or another, but they don't split cleanly along the lines he wants. I study embryology, for instance, but I'm not looking at macroevolutionary events -- I'm studying epigenetics and intraspecific variation. I also don't understand how this works from his point of view. He doesn't believe in macroevolution. Does that mean that comparative anatomy, embryology, and paleontology lack any integrating foundation? Again, that is completely wrong.

Malachi256's post was an appalling muddle. Faust ought to have an easy time ripping it apart...and then the interesting bit is going to be when he tries to argue for an absence of a meaningful distinction. We can have another roast tomorrow -- I hope he's a bit meatier and doesn't have that rancid aftertaste.