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When You Think Of Microevolution, What Are You Thinking Of ?


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#1 aelyn

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Posted 26 June 2012 - 03:14 AM

Microevolution is something that comes up a lot in these debates and I think it's one thing everyone here agrees happens.
I want to learn more about what microevolution means to creationists, beyond plain definitions, so I was wondering whether the creationists here could help me with a few questions:

When you think of microevolution, what are three typical examples of microevolution that come to mind ? (like, a group of organisms which all micro-evolved from a common ancestor or small group of interbreeding common ancestors)

What are the three most extreme cases of microevolution you can think of ? (i.e. the three groups of organisms that micro-evolved from a common ancestor that are the most different amongst themselves in your mind)

And if possible, what factors do you think are important for telling groups that have a common ancestor from groups that don't ? (I'm not looking for precise criteria, just an overview of which elements you think matter to the question. Though if you have precise criteria you can give that instead if you wish)

Thank you ! :)

#2 gilbo12345

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Posted 26 June 2012 - 07:22 PM

One example is benign changes that cannot lead to new structures or forms ie- different hair / skin / scale / fur colour. These are merely variations within an existing structure hence cannot lead to new structures therefore new organisms forming.

#3 gilbo12345

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Posted 01 July 2012 - 05:56 AM

One example is benign changes that cannot lead to new structures or forms ie- different hair / skin / scale / fur colour. These are merely variations within an existing structure hence cannot lead to new structures therefore new organisms forming.


This logic would then render the different colour of moths "evidence" out of the window... Yes perhaps the moths get eaten and a different colour becomes dominant.... Will this new colour mean the moth now "evolves" into something other than a moth with different colours?

If yes then how does a new colour bring about new structures? and where is the evidence for this?


If no then why are changes in colour stated as evidence for bacteria to man evolution in the textbooks? (I was taught it at 2nd year university Biology, last year). This therefore demonstrates intellectual dishonesty for the sole purpose of indoctrination.



As I have already stated benign variations are not evidence of major structural changes which lead to new structures and therefore new species.

#4 herebedragons

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Posted 10 July 2012 - 08:07 AM

Microevolution is something that comes up a lot in these debates and I think it's one thing everyone here agrees happens.
I want to learn more about what microevolution means to creationists, beyond plain definitions,


My position in this debate is such that I really don't like to associate with either label: "creationist" or "evolutionist". Maybe a creationist who accepts evolution??? And I don't have any specific examples because I still feel the distinction between micro and macro is murky to say the least. But I have been thinking of a definition of sorts that I thought I could run by you here since you are not getting many other responses

I would consider microevolution to be changes that we can observe and study ... such as the distribution of plethodontid salamanders in the Appalachian mountains - Plethodon cylindraceus and P. teyahalee.

Whereas macroevolution is inferred changes that we cannot directly observe, but we base the inference on known mechanisms of speciation that are observed and studied.

I think these definitions solve some of the concerns about macroevolution by not eliminating the possibility of specific events, but also not giving it the same weight as observed instances.

I know this is not the definition used by scientists and I don't expect that scientists will rush to adopt my definition, but do you think it could help promote understanding? especially on forums such as this?

Again, I really don't have specific examples since I don't really know where to draw the line between micro and macro.

HBD

#5 Mountainboy19682

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Posted 15 July 2012 - 11:01 PM

The accepted use of the term microevolution in biology dates from a 1937 book by Theodosius Dobzhansky called Genetics and the Origin of Species. By it he meant genetic change within a species. In the wild an example is the Kodiak bear - which has been geographically and genetically isolated from other North American Brown Bears for about 10,000 years.

Another interesting example of microevolution are the Lesser Black-backed Gulls and Herring Gulls, which some biologists consider to be a ring species. They have a circumpolar range and both occur in Europe, where they do not interbreed (and are then by definition separate species). However they have intermediates around the world in Asia and North America which do interbreed.

Among domesticated animals, the most spectacular example of intra- species variation must be between Chihuahuas and Great Danes, which can only interbreed with great difficulty.

Interestingly there are many Creationists who are much more creative and enthusiastic about the capability of microevolution. They do this in order to cut down on the number of animals that Noah would have needed to transport in his ark. They suggest that all the species around today would have radiated by microevolution from a more restricted number of baramin. Some sources suggest that a baramin is roughly equivalent to what biologists classify as a Family

For example at http://www.answersin...igers-wholphins Dr. Georgia Purdom and Bodie Hodge seem to suggest that all of what biologists call the family Felidae were one baramin represented on the ark by a single pair of animals. After the ark landed this group gave rise to all the living Felidae which includes the tiger, the lion, the jaguar, the leopard, the cougar, the cheetah, the lynxes, the ocelot, and the domestic cat and presumably the extinct ones such as Smilodon. This is pretty extreme microevolution over a period of 4,500 years. Actually much less since domestic cats were known to the ancient Egyptians, and must by then have microevolved away from Smilodon in less than 1500 years. Mainstream biologists put the last common ancestor of the different Felidae species at about 25 million years ago.

#6 aelyn

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Posted 25 November 2012 - 02:15 AM

Thank you the responses, and sorry I wasn't there to address them. I was hoping to get some more ideas as I've seen many discussions of macro vs microevolution in other threads that involved examples of what various people felt were one or the other. For example NewPath talked about marsupials being the result of micro-evolution because of genetic markers, a point of view I hadn't heard before.
That was why I started this thread, I wanted to get an idea of where and how different people drew the line.

Gilbo, thank your for your answers that give some insight into which traits you think distinguish macro evolution from micro-evolution, and some examples of what I'll assume you consider “typical” micro-evolution (colour change in moths). Do you have any examples in mind that you would consider closer to the limit – extreme examples of micro-evolution that you're still comfortable calling micro-evolution, or examples of the smallest changes you can think of that would be impossible via micro-evolution but would count as macro-evolution ?

Here be dragons : Your proposed definition is interesting, but if you define microevolution as changes that have been directly observed and studied and macroevolution as changes that haven't, then that makes the claim that macroevolution hasn't been observed completely tautological, a consequence of your definition and not of any intrinsic limit to evolutionary change. It can be a useful definition for some purposes, but not the purpose of discussing whether there are any limits to evolutionary change or not, and that is usually what the macro/microevolution distinction is for in creation/evolution debates.

@Mountainboy : those issues with defining macro-evolution vs micro-evolution are the reason I was asking this question; get away from looking for perfect definitions for a minute and try instead to explore the concepts different people associate with each word... That's also why I was really hoping for more people like Gilbo to answer, people who talk a lot about micro-evolution and macro-evolution and have some specific ideas about what each word entails.

#7 gilbo12345

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Posted 25 November 2012 - 02:33 AM

Gilbo, thank your for your answers that give some insight into which traits you think distinguish macro evolution from micro-evolution, and some examples of what I'll assume you consider “typical” micro-evolution (colour change in moths). Do you have any examples in mind that you would consider closer to the limit – extreme examples of micro-evolution that you're still comfortable calling micro-evolution, or examples of the smallest changes you can think of that would be impossible via micro-evolution but would count as macro-evolution ?


No worries :) Thanks for the pleasant reply :D


Changes in relative sizes of a species... ie- big dogs and small dogs but are still dogs... Would be what I regard as extreme forms of micro-evolution since it does change the basic body plan, (though only in size not in features).

#8 herebedragons

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Posted 28 November 2012 - 08:25 AM

Hi aelyn ...

Your proposed definition is interesting, but if you define micro-evolution as changes that have been directly observed and studied and macroevolution as changes that haven't, then that makes the claim that macro-evolution hasn't been observed completely tautological,



That was pretty much my intention, or more like make the argument that macro-evolution hasn't been observed a moot point. But at the same time, there is more weight on the reliability of the evidence for micro-evolution because it has been observed. If macro-evolution has not been directly observed then it is inferred. These have different levels of confidence in the reliability of the conclusions.

I have not yet found a completely satisfactory definition of macro-evolution (satisfying to all parties.) that clearly distinguishes between the two. One kind becoming another kind is vague to say the least. Evolution above the species level is kinda shaky for a couple reasons. Assignment of taxonomic levels is rather arbitrary and doesn't have a clearly defined delineation of its own. So just because an organism is described as a new genus, isn't especially convincing. Also, with orchids for example, evolution of new genus have been observed, but they are still fertile across genus lines, so that becomes difficult to establish as macro-evolution. Any distance between species that would qualify as macro-evolution would be completely arbitrary and not agreed upon by both parties.

I feel the definition I gave would help the discussion by focusing on why the inferences for specific cases of claimed macro-evolution are valid / invalid rather than the response simply being "Oh that's just micro-evolution because it is not a different kind." Observed cases of speciation are not what is contested, it is the cases that are not directly observed, but are proposed from inferences that are the subject of debate.

I know this is not the scientific definition of macro-evolution and I wouldn't expect that it would ever become adopted in that way, but since this issue of micro vs. macro is only debated on forums such as this in the context of creation vs evolution, it may help make for better communication between opposing view points, that's all.

HBD

#9 Calypsis4

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Posted 28 November 2012 - 08:50 AM

What do I think of microevolution? First, it isn't 'evolution' in the first place...at least not be any Darwinian idea of the term. It is merely change...a variation within a type/kind/family of organism.

Like this:

Posted Image

After 50,000 generations of experimentation on this organism...it was still a fly.

But let aelyn or any other skeptic show us that the drosophlia fly has 'evolved' into any other type of organism. Let them give us an observable example. And not just the drosophila but that goes for any other class of organism and let them prove genetically that such a thing has happened. Let us see if they can come up with an example that violates God's Law that all living things remain in the same class 'after it's kind'.

(Note: by 'class' I mean the classification of 'family' or higher on the Linneaus classification system).

#10 herebedragons

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Posted 28 November 2012 - 10:05 AM

Hi Calypsis ...

Note: by 'class' I mean the classification of 'family' or higher on the Linneaus classification system



So your definition of macro-evolution is change above the family level? What if a taxonomist decided that (working form your image) D. simulans, D. sechellia, D. melanogaster, D. yakuba and D. erecta should be moved to a different family than the rest of the flies in the chart? Would that make it macro-evolution? The taxonomic classification of organisms is rather arbitrary and based on human criteria. For example, Diptera (in the image below) are distinguished by having a pair of flight wings on their mesothorax and a pair of halteres on their metathorax. Why is this a suitable way to classify them as an order?

A newer classification schemes is cladistics which try to arrange organisms in a "natural" scheme based on their evolutionary history. But other than a historical scheme (from either a creationist or evolutionist perspective), what is it that confirms that two species are the same "kind?"

The image below is of six different flies. How do you determine if they are the same "kind" or not. They are all flies.

Posted Image

All six examples are members of different families of the same order: Diptera - the true flies.

Without a historical classification scheme it is not really possible to determine if these six flies descended from a common organism that left the ark or from six different organisms. So how could you determine that? Is it merely intuitive?

But let aelyn or any other skeptic show us that the drosophlia fly has 'evolved' into any other type of organism. Let them give us an observable example. And not just the drosophila but that goes for any other class of organism and let them prove genetically that such a thing has happened. Let us see if they can come up with an example that violates God's Law that all living things remain in the same class 'after it's kind'.



Your argument may have an emotional appeal to it but there is just no practical application of it. Without a historical classification scheme, there is just no way to determine what a "kind" even is. And it is this very historical classification scheme which is rejected. So ...

HBD

#11 gilbo12345

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Posted 28 November 2012 - 10:20 AM

They are all flies.


Case in point ;)
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#12 herebedragons

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Posted 28 November 2012 - 12:57 PM

Case in point ;)/>


Does that mean you would say that all 6 of these families of flies are all of the same "kind" and diversified from a single created kind?

There are over 10,000 described species in those 6 families. Any idea how they would have diversified from a single kind? ;)

HBD

#13 Calypsis4

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Posted 28 November 2012 - 02:27 PM

Hi Calypsis ... So your definition of macro-evolution is change above the family level? What if a taxonomist decided that (working form your image) D. simulans, D. sechellia, D. melanogaster, D. yakuba and D. erecta should be moved to a different family than the rest of the flies in the chart? Would that make it macro-evolution? The taxonomic classification of organisms is rather arbitrary and based on human criteria. For example, Diptera (in the image below) are distinguished by having a pair of flight wings on their mesothorax and a pair of halteres on their metathorax. Why is this a suitable way to classify them as an order? A newer classification schemes is cladistics which try to arrange organisms in a "natural" scheme based on their evolutionary history. But other than a historical scheme (from either a creationist or evolutionist perspective), what is it that confirms that two species are the same "kind?" The image below is of six different flies. How do you determine if they are the same "kind" or not. They are all flies. Posted Image All six examples are members of different families of the same order: Diptera - the true flies. Without a historical classification scheme it is not really possible to determine if these six flies descended from a common organism that left the ark or from six different organisms. So how could you determine that? Is it merely intuitive? [/font][/color] Your argument may have an emotional appeal to it but there is just no practical application of it. Without a historical classification scheme, there is just no way to determine what a "kind" even is. And it is this very historical classification scheme which is rejected. So ... HBD



1. There is no 'macro-evolution' because evolution does not exist in the first place. Degeneration is the [/color][/font]natural order of things and you neo-Darwinians have got it all backwards.

2. Why would anyone change the classifications? Though it isn't perfect nor infallible like God, the Linneaus system is still a fairly good frame-work for what we observe. Nonetheless, the systme is arbitrary and subject to human opinion.

3. How do we determine if they are the same kind of not? Answer: by the genetics. It's what comes out in the wash. That which produces viable offspring without genetic engineering determines what is or is not of the same 'kind'.
You also stated, "A newer classification schemes is cladistics which try to arrange organisms in a "natural" scheme based on their evolutionary history." You mean the 'assumed history'. We don't accept that so-called history.

4. You said, " it is not really possible to determine if these six flies descended from a common organism that left the ark or from six different organisms." Flies didn't need to be on the ark. Why? Uh..............because they can..........fly?

5. You said, "Without a historical classification scheme, there is just no way to determine what a "kind" even is."

But you fail to grasp that the same thing is true of the word species, which several of your evolutionist comrades have admitted: Quote: "The 'species problem' is perennial (Howard, 1988), and speciation remains as much a black box as ever (Jackson, 1988). If we examine these problems we find a spectrum of solutions: some writers claim that everything, or everything important, is known; others claim that nothing, or nothing important, is known (Hull, 1988). I claim that the problems are insoluble, for they stem from a false assumption: that there is an empirical difference between species and the taxa such that species evolve through speciation of other species.... Evolution of taxa is not a phenomenon confined to the species level except in neodarwinian theory, which in this respect is simply false." G. Nelson, Species and Taxa: Systematics and Evolution, in D. Otte and J.A. Endler, Speciation and its Consequences (Sunderland, Massachusetts), Sinauer, 1989) pp. 73,74.

6. You said, "And it is this very historical classification scheme which is rejected." Rejected by whom? In the country where I live, creationism is in the majority, as it is in Korea and other places.

7. Gilbo was correct.
Your chart reveals the truthfulness of our position. One may begin with flies but he will always end up with flies. That's the bottom line.

#14 gilbo12345

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Posted 28 November 2012 - 04:47 PM

Does that mean you would say that all 6 of these families of flies are all of the same "kind" and diversified from a single created kind? There are over 10,000 described species in those 6 families. Any idea how they would have diversified from a single kind? ;)/> HBD


Its called variation.....

No-one that I know of here argues against the fact that organisms have the ability to change and adapt. However what we do get antsy about is the unfounded extrapolation that such benign variation would ever lead to new forms of organisms (thus new kinds / species / whatever you wish to call them). Since the extrapolation is unfounded its very hard to reconcile it with science.

Consider that what we do observe are benign changes which do not affect the basic body plan of the organism... Check out all the types of dogs, hey may be different to each other but they all share the same basic form, the same is with all these flys (which you claimed are all flys which is the point just there).

#15 herebedragons

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Posted 03 December 2012 - 06:34 PM

There is no 'macro-evolution' because evolution does not exist in the first place.


That's a lousy definition. The OP is trying to understand what you consider to be "macro-evolution." What would you recognize as "macro-evolution?" The point is to create dialogue, to promote understanding so the discussion can move forward.

In the example of the order Diptera I gave, if all those different families and species of flies came from one common ancestor (as you suggest is possible since they are all flies) a scientist would consider that "macro-evolution." You say it is "micro-evolution" or adaptation. Why would you not consider that amount of diversification to be "macro-evolution?" Is it a terminology problem?

Why would anyone change the classifications?


Happens all the time. As evidence accumulates and new data is collected, classifications change as taxonomists better understand relationships. A family level reclassification that has occurred recently is the genus Acer from the family Aceraceae has been moved to a different family, Sapindaceae because molecular evidence showed that the genus Acer was more closely related to the Sapidales than it was to its previous location. Actually, the kingdom Plantae is being shook up rather thoroughly with new molecular evidence.

Flies didn't need to be on the ark. Why? Uh..............because they can..........fly?


Come on ... Birds can fly but they were on the ark. I can't imagine insects surviving the torrential rains that would have been required to flood the entire earth. But even had they not been on the ark and survived the flood, it is still an incredible amount of diversification to occur in 6,000 years.

But you fail to grasp that the same thing is true of the word species


No I don't fail to grasp the problem. Yes, there is problems with the definition of species. The problem is that organisms don't care how humans classify them, they only care about how they see themselves. What you fail to grasp is the difficulty in defining "kind" and creating arbitrary boundaries that cannot be crossed.

Rejected by whom? In the country where I live, creationism is in the majority, as it is in Korea and other places.


Cladistics is a example of a historical classification scheme. Any classification scheme that attempts to organize organisms based on their evolutionary history is rejected. Is there another type of history of an organism? The "adaptive" history perhaps? How would that be different from what we already have?

Gilbo was correct. Your chart reveals the truthfulness of our position. One may begin with flies but he will always end up with flies. That's the bottom line.


OK. They are all flies. But that completely misses the point. If these flies diversified from a single common ancestor, then they have crossed the arbitrary line of family that you suggested in message 9. That would make it "macro-evolution", no?

So ... How about a working definition for "macro-evolution?"

How did you like my definition in msg #4 "I would consider microevolution to be changes that we can observe and study ... Whereas macroevolution is inferred changes that we cannot directly observe, but we base the inference on known mechanisms of speciation that are observed and studied."

Would a definition like that make discussion of the subject easier?

HBD

#16 Calypsis4

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Posted 03 December 2012 - 06:49 PM

herebedragons

That's a lousy definition.

I didn't give you a definition I gave you a fact. This world is degenerating....from an original perfection created by God. The world is doing just the opposite to what neo-Darwinian theory tells us. It's going to be embarrassing when that reality finally hits you and those of your persuasion.

The OP is trying to understand what you consider to be "macro-evolution." What would you recognize as "macro-evolution?"

Well, if it did exist it would have to exist in direct conflict with natural law. (Biogenesis, the 2nd Law of Thermodynamics, etc.) But...Posted Image You see, we find fossils of bats in the fossil record and we find fossils of rodents....BUT...there are no bat/rats in the fossil record...nor anything close to a transitional change between small rodent-like creatures and the modern bat.

The point is to create dialogue, to promote understanding so the discussion can move forward.

What you mean is that you want us to come to an agreement with you about evolution. We don't.

9. That would make it "macro-evolution", no?

No. God's law says that all creatures He made are 'after its kind' and that means that genetically no plant nor animal will produce offspring that are different than the family they sprang from. There are no exceptions and evolution is an error. Read Mendel.

#17 herebedragons

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Posted 03 December 2012 - 07:51 PM

herebedragons I didn't give you a definition I gave you a fact.

You mean opinion.

It's going to be embarrassing when that reality finally hits you and those of your persuasion.

You don't know "my persuasion" from a few posts on the internet.

What you mean is that you want us to come to an agreement with you about evolution. We don't.


Honestly, No, not what I mean at all. It is impossible to discuss something when both parties define it differently. Having an understanding of each others definition would make conversation easier.

Well, if it did exist it would have to exist in direct conflict with natural law. (Biogenesis, the 2nd Law of Thermodynamics, etc.)

How so? We are not talking about abiogenesis here. We are not talking about thermodynamics, we are talking about heritable changes that accumulate over time. You accept that adaptation can happen. That is also heritable changes that accumulate over time, but you impose a limit on that change. What is that limit - in quantifiable terms?

God's law says that all creature He made are 'after its kind' and that means that genetically no plant nor animal will produce offspring that are different than the family they sprang from.

If a plant or animal produces offspring that are different from the family that they sprang from it would falsify the ToE. The ToE says that forms change gradually, small steps at a time. "After its kind" doesn't restrict changes to an arbitrary family classification. I already showed you that family classification can change, but a created kind cannot change. Maybe its class or order or phylum or maybe kingdom that defines a kind. What does "kind" mean? God doesn't specifically spell that out in Genesis.

So what would qualify as "macro-evolution?" A bat/rat creature?

I also doubt the bacteria to man evolutionary scheme. I am certain some things have evolved or adapted as you prefer to call it. But where do we draw the line? What is macro-evolution? What is the line that evolution cannot cross as organisms change over time?

HBD

#18 Calypsis4

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Posted 04 December 2012 - 01:17 PM

Serious technical problems posting so I erased this post.

#19 aelyn

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Posted 15 December 2012 - 11:27 AM

Thank you all for the discussion, it's very interesting. On re-reading though I was very surprised at one thing Calypsis said so I'd like a clarification on this bit :

3. How do we determine if they are the same kind of not? Answer: by the genetics. It's what comes out in the wash. That which produces viable offspring without genetic engineering determines what is or is not of the same 'kind'.

Are you saying that your criterion for "kind" is being able to interbreed and produce viable offspring ? So if there was a single interbreeding population that split into several populations and individuals from those different populations were no longer able to produce viable offspring without any genetic engineering involved, that would be an example of macro-evolution for you ?

Given your later answer to Here Be Dragons it looks like the answer would be "no", but then that would suggest that interbreeding isn't the only thing that defines a "kind" to you; what other factors would you say there are ?

And while I'm here...

Its called variation..... No-one that I know of here argues against the fact that organisms have the ability to change and adapt. However what we do get antsy about is the unfounded extrapolation that such benign variation would ever lead to new forms of organisms (thus new kinds / species / whatever you wish to call them). Since the extrapolation is unfounded its very hard to reconcile it with science. Consider that what we do observe are benign changes which do not affect the basic body plan of the organism... Check out all the types of dogs, hey may be different to each other but they all share the same basic form, the same is with all these flys (which you claimed are all flys which is the point just there).

You talked earlier about "typical" microevolutionary changes being changes in color and so on, and that you felt changes in size such as that seen in dogs was an extreme case since it involved a change in body plan, but in that post you seem to say that the differences between flies (i.e. members of the order Diptera) would also qualify as micro-evolution. This seems to me to include quite large differences. See these :
http://en.wikipedia....logy_of_Diptera
http://en.wikipedia....logy_of_Diptera
There are flies that look like ants, others that look like bees, others that look like moths, others that look like spiders. Some flies bioluminesce. Some flies have eyes on stalks. Some flies have huge eyes with thousand of ommatidia that take up the whole head, others have tiny eyes. Some flies have long, feathery articulated antennae made of 7 to 15 parts, others have tiny bristle-like antennae made of 3 to 6 parts. Some have piercing and sucking mouthparts while others have rasping or sponging ones (think of mosquito vs housefly...). Some flies have calyptrae, membranes that protect the halteres, others don't. They have different patterns of wing veins. Their larvae have different breathing systems. Some males wrap prey in silk to present to the female as a courtship ritual.


This seems to me to include much more dramatic differences than are seen between dogs, what do you think ?

#20 gilbo12345

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Posted 16 December 2012 - 04:11 AM

Some pictures would go a long way to support your claims




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