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Author Topic:   Is There Any Genetic Or Morphological Criterion For "Kind"?
Dr Adequate
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Posts: 16093
Joined: 07-20-2006
Member Rating: 9.1


Message 16 of 40 (352465)
09-26-2006 8:09 PM
Reply to: Message 12 by mjfloresta
09-26-2006 5:52 PM


Your defintion seems at odds with at least one popular brand of creationism. The following is taken from AiG:

Take a hypothetical created kind A—truly a biological ‘species’ with perhaps a tremendous genetic potential. See Figure 1. (For the sake of simplicity, the diagram avoids the issue of what is meant by two of each kind aboard the Ark—however, the basic point is not affected.) Note that A may even continue as an unchanged group, as may any of the subgroups. Splitting off of daughter populations does not necessarily mean extinction of the parent population. In the case of man, the original group has not diverged sufficiently to produce new species.

Hence, D1, D2, D3, E1, E2, E3, P1, P2, Q1, Q2, Q3 and Q4 are all different species, reproductively isolated. But all the functionally efficient genetic information they contain was present in A. (They presumably carry some mutational defects as well). *

You see the dodge? By their theory of evolution-but-we-don't-call-it-that, they can have reproductively isolating speciation starting from just one kind.

Other creationist websites I've looked at seem to concur. So mere interbreeding would be a sufficient condition for two animals to be the same kind, but not a necessary condition.

So what is?

You'll notice that the author I reference does not answer that question, preferring to put up a flimsy smokescreen of lies and rhetoric.

Edited by Dr Adequate, : No reason given.


This message is a reply to:
 Message 12 by mjfloresta, posted 09-26-2006 5:52 PM mjfloresta has not yet responded

Replies to this message:
 Message 27 by ggghg7, posted 12-09-2011 9:03 PM Dr Adequate has responded

  
Dr Adequate
Member
Posts: 16093
Joined: 07-20-2006
Member Rating: 9.1


Message 17 of 40 (352509)
09-26-2006 11:02 PM
Reply to: Message 7 by mjfloresta
09-26-2006 11:37 AM


On the other hand, the ICR seem to be leaning the other way:

"A kind may be defined as a generally interfertile group of organisms that possesses variant genes for a common set of traits but does not interbreed with other organisms under normal circumstances." (ICR Impact, "Summary of Evidence for Creation", May/June 1981)

My italics; so their definition of "kind" is more stringent than yours.

Will the real creationism please stand up?


This message is a reply to:
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Faith
Member
Posts: 30900
From: Nevada, USA
Joined: 10-06-2001
Member Rating: 1.1


Message 18 of 40 (352521)
09-27-2006 12:18 AM
Reply to: Message 6 by Quetzal
09-26-2006 8:52 AM


However, adding in the part about "certainly the same 'kind'" even though reproductively isolated leaves us back in the same place, without a usable definition. "'Kind' = ability to interbreed except when they can't" isn't very useful.

I know. I should not have added my doubtful thought at the end, which contradicted the first part as you say. Just because they don't doesn't mean they can't. The fact that many don't proves nothing in other words.

I was thinking of a frog species somebody posted about on another forum a long time ago, and I don't remember its name, but it's a member of the frog kind and there is no doubt, not something new. HOw do I know? I don't know. It's just obvious.

I'd also like your opinion concerning the second part of the question: how do you determine whether two fossils are the same "kind"? Obviously, an interbreeding test isn't going to work. So what's the criteria?

I don't know enough fossils myself to ponder the possibilities. Something in the morphological department would have to be relevant. I was impressed at a posting once of the Karoo formation which is full of reptilian swimming things that I'd have to say are clearly of the same Kind although they vary from each other in interesting ways. I may be misremembering.

I'm tempted to say that whatever most people would be inclined to call the thing (at least in most cases -- there would always be exceptions) is probably close to a definition of the Kind.

But the fact is we don't have a definition. We have feelings about what a Kind would include, and I think the list of hybrids kuresu posted is intuitively satisfying. I also think ability, apart from inclination, to interbreed, seems relevant. And morphology too of course, but that's not easy to define either.

Someday it will have to be genetically defined. Or maybe Jesus will come back first.

Edited by Faith, : No reason given.


This message is a reply to:
 Message 6 by Quetzal, posted 09-26-2006 8:52 AM Quetzal has responded

Replies to this message:
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Dr Adequate
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Posts: 16093
Joined: 07-20-2006
Member Rating: 9.1


Message 19 of 40 (352566)
09-27-2006 5:32 AM
Reply to: Message 18 by Faith
09-27-2006 12:18 AM


FSTDT.
This message is a reply to:
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Replies to this message:
 Message 20 by RickJB, posted 09-27-2006 6:59 AM Dr Adequate has not yet responded
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RickJB
Member (Idle past 3096 days)
Posts: 917
From: London, UK
Joined: 04-14-2006


Message 20 of 40 (352577)
09-27-2006 6:59 AM
Reply to: Message 19 by Dr Adequate
09-27-2006 5:32 AM


http://www.fstdt.com/
This message is a reply to:
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Quetzal
Member (Idle past 3977 days)
Posts: 3228
Joined: 01-09-2002


Message 21 of 40 (352620)
09-27-2006 11:58 AM
Reply to: Message 18 by Faith
09-27-2006 12:18 AM


I know. I should not have added my doubtful thought at the end, which contradicted the first part as you say. Just because they don't doesn't mean they can't. The fact that many don't proves nothing in other words.

Well, if you mean "don't in the wild", then you're right - it doesn't prove much. It also doesn't help the definition of "kind" we're trying to reach. MJFloresta insists that the interbreeding criteria is the sole determinant. As you pointed out, that doesn't always work - there are a lot of organisms that are superficially similar (you mentioned a morphological criteria as the "fall back" - which of course ran us smack into the reproductive wall contradiction you recognize here) that simply can't interbreed, regardless of circumstances. Not "don't want to", but actually can't produce fertile hybrids (see next).

I was thinking of a frog species somebody posted about on another forum a long time ago, and I don't remember its name, but it's a member of the frog kind and there is no doubt, not something new. HOw do I know? I don't know. It's just obvious.

This brings to mind an example that might be illustrative of the problem any definition of "kind" needs to overcome. Remember this little cutie?


Click to enlarge
It is a glass frog of the family Centrolenidae, which includes glass frogs and leaf frogs, that we found in the reserve I'm working in. Clearly, it is "frog kind". Morphologically (at least superficially), they resemble the Hylidae, or tree frogs, as many of the latter are small, green, and dwell in the canopy like the Centrolenidae in Ecuador. They even sound, to the untrained ear, like each other (they're both peepers). However, the details of their morphology (they have multiple different structures, even different organs), behavior, genetics, etc, make it literally impossible for them to mate - even artificially: the chromosomes don't line up properly* - they are not interfertile by any stretch. Your "I just know it" definition of "kind" - an objectively useless distinction - is the only way these two families can be considered the same. Genetically, reproductively, morphologically, behaviorally, and even in terms of ecological role, parental care, egg-laying strategies, etc, they are very different groups of organisms. Where can you draw the "kind" line?

I'm tempted to say that whatever most people would be inclined to call the thing (at least in most cases -- there would always be exceptions) is probably close to a definition of the Kind.

Unfortunately, "whatever most people would be inclined to call the thing" doesn't provide any real possibility of distinguishing one group of organisms from another. For example, what is an "elk"? The common name “elk” (what most people are inclined to call the thing) describes very different organisms in Europe and North America, even though the term is used in both places. A European “elk” is called a moose in North America, whereas the North American “elk” is referred to by Europeans as a “red deer”. Add in recently vanished organisms such as the “Irish Elk” – a type of fallow deer – and anyone attempting to communicate any kind of useful information about the critter is completely at sea, awash in conflicting nomenclature. Common names are pretty worthless outside of really obvious things like "dog", "cat", "sheep", etc. Even here, the differences between what scientists call Felis catus, and say Puma concolor or Leopardis pardalis render "cat" a fairly worthless piece of nomenclature from any practical standpoint. This is pretty much the entire reason why Linnaeus came up with the binomial nomenclature in the first place. If you're going to replace this with "kind" - for whatever reason - it's got to be at least as useful and operationally defined as what is now in use. Until you (generically speaking - I'm aware you personally don't have more than a vague idea on the subject), can do this, I see no reason for anyone to take the "kind" term seriously.

Someday it will have to be genetically defined. Or maybe Jesus will come back first.

If I were you, I'd bet on the latter, since genetics not only doesn't support the concept, but quite clearly refutes its existence.

*Before you ask - no, no one has attempted to perform this experiment. Why would they? The chromosomes are so different, the arrangement of functional genes so different, that there is clearly no way for it to work. Eggs from the one simply physically can't be fertilized by sperm from the other.


This message is a reply to:
 Message 18 by Faith, posted 09-27-2006 12:18 AM Faith has not yet responded

  
Quetzal
Member (Idle past 3977 days)
Posts: 3228
Joined: 01-09-2002


Message 22 of 40 (353099)
09-29-2006 10:15 AM


Bumpity Bump for Faith
I know you have a lot of threads you are currently involved with, but I would appreciate your reply to my previous (post #21).
  
Dr Adequate
Member
Posts: 16093
Joined: 07-20-2006
Member Rating: 9.1


Message 23 of 40 (621755)
06-28-2011 4:56 PM


Bump
* bump *
  
Minority Report
Member (Idle past 1259 days)
Posts: 66
From: N.S.W Australia
Joined: 05-25-2009


Message 24 of 40 (621827)
06-29-2011 6:33 AM
Reply to: Message 1 by Dr Adequate
09-25-2006 3:28 PM


Define Kind?
Hi Dr A,
Here's another article that may help a little; www.creation.com/ligers-and-wholphins-what-next

Basically it says that defining a kind as being a species is too narrow a definition, and that in some situations a kind may go up the taxonomic clasification as far as order. Because of differing amounts of speciation between the original created kinds, you cannot state that a 'kind' is equivalent to say 'family' across the board. One kind may extend back to family, another may go to order, and still another may be equvalent to genus.


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 Message 1 by Dr Adequate, posted 09-25-2006 3:28 PM Dr Adequate has responded

Replies to this message:
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frako
Member
Posts: 2813
From: slovenija
Joined: 09-04-2010


(3)
Message 25 of 40 (621834)
06-29-2011 8:46 AM
Reply to: Message 24 by Minority Report
06-29-2011 6:33 AM


Re: Define Kind?
Damm ethics and morals someone should make a humanzee to shut the creos up.
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Dr Adequate
Member
Posts: 16093
Joined: 07-20-2006
Member Rating: 9.1


Message 26 of 40 (621849)
06-29-2011 9:23 AM
Reply to: Message 24 by Minority Report
06-29-2011 6:33 AM


Re: Define Kind?
That tells me that this particular group of creationists aren't identifying "kinds" with some particular taxonomic rank, but it doesn't tell me how they should in fact be identified.
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ggghg7
Junior Member (Idle past 1958 days)
Posts: 3
Joined: 12-08-2011


Message 27 of 40 (643647)
12-09-2011 9:03 PM
Reply to: Message 16 by Dr Adequate
09-26-2006 8:09 PM


Baraminology
Hello,
Perhaps the most specific reference to baraminology (the creation science version of taxonomy) can be found here: http://objectiveministries.org/creation/baraminology.html

Essentially it does seem like a regurgitation of the biological speces concept, but it's an elegant attempt by 'creation scientists.'


This message is a reply to:
 Message 16 by Dr Adequate, posted 09-26-2006 8:09 PM Dr Adequate has responded

Replies to this message:
 Message 28 by Coyote, posted 12-09-2011 9:37 PM ggghg7 has responded
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Coyote
Member (Idle past 211 days)
Posts: 6117
Joined: 01-12-2008


Message 28 of 40 (643649)
12-09-2011 9:37 PM
Reply to: Message 27 by ggghg7
12-09-2011 9:03 PM


Re: Baraminology
Essentially it does seem like a regurgitation of the biological speces concept, but it's an elegant attempt by 'creation scientists.'

Welcome to the fray!

Baraminology has a primary fault in that it completely ignores the scientific method in favor of religious apologetics.

In other words, there is no way the answer can come out in opposition to creationists' interpretation of the bible. And creationists will do anything they need to do in order for that to occur.

This is pretty much the exact opposite of science.


Religious belief does not constitute scientific evidence, nor does it convey scientific knowledge.

This message is a reply to:
 Message 27 by ggghg7, posted 12-09-2011 9:03 PM ggghg7 has responded

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Dr Adequate
Member
Posts: 16093
Joined: 07-20-2006
Member Rating: 9.1


Message 29 of 40 (643653)
12-09-2011 11:30 PM
Reply to: Message 27 by ggghg7
12-09-2011 9:03 PM


Re: Baraminology
Hello,
Perhaps the most specific reference to baraminology (the creation science version of taxonomy) can be found here: http://objectiveministries.org/creation/baraminology.html

Essentially it does seem like a regurgitation of the biological speces concept, but it's an elegant attempt by 'creation scientists.'

Objective Ministries is a parody site, albeit a subtle one.


This message is a reply to:
 Message 27 by ggghg7, posted 12-09-2011 9:03 PM ggghg7 has not yet responded

  
Kaichos Man
Member (Idle past 2593 days)
Posts: 250
From: Tasmania, Australia
Joined: 10-03-2009


Message 30 of 40 (643817)
12-12-2011 5:30 AM
Reply to: Message 1 by Dr Adequate
09-25-2006 3:28 PM


Bin a long time
Greetings, physician.

How do we understand the biblical "kinds"? A fair, but difficult question. To understand the difficulty, we must first compare the concept of "kind" to its evolutionary equivalent.

Evolution believes that all of life evolved from a single living cell, moving through many stages of increased morphological complexity en route to the diversity we now witness.

Obviously, this means that life passed through a number of evolutionary watersheds, and these major transition points are afforded categories under the science of taxonomy: kingdom, phylum, class, genus, order, family and species.

For the most part, this has been an orderly process; there has been some reclassification and reallocation, but that's to be expected.

"kinds", on the other hand, suggest that biological diversity had a much more complex starting point; from a set number of highly complex organisms aboard the Ark, through speciation, to the multiplicity of species we encounter today.

I agree with many other people that "family" is the taxonomic level that best approximates "kind". But as taxonomy has seen some retrospective reshuffling (and no doubt will see more in the future) "kinds" will not neatly fit into the "family" classification, and will also need ongoing revision.

For me the solution is simple. I would place creatures of obvious phenotypic similarity into the same Kind- as long as they did not exhibit a genetic complexity greater than that exhibited by the majority of established members of that Kind (increased genetic complexity being defined as more coding DNA, resulting in a biological feature or function additional to all of those enjoyed by the other members.)

This would allow for the diversity created by simple speciation, without requiring the problematic increase in genetic complexity which, as we all know, has never been observed or documented.

Polymer-metabolising microbes not withstanding, of course.


"When man loses God, he does not believe in nothing. He believes in anything" G.K. Chesterton

This message is a reply to:
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