Richiyaado

Thanks, theyeti. I'm not a scientist, only an interested layperson, so I'm prone to making many misteaks. Oops, made another one!

babelfish

I second that prediction....

Not impressed with Douglas Bender's arguments so far...

Douglas J. Bender

(Hey, everyone, I prefer "Douglas". Thanks.)


wonderbread,


You said:
You mean, like monks and nuns? I'm afraid you'll have to briefly explain organisms that are "asexual", before I can respond to this (I'll try to research a little, myself).


I never said it would be easy to do. Are you trying to argue that a definition is faulty, just because checking whether some things fit it would be difficult?


No, that would be unethical, in my opinion. Has genetics advanced far enough that some kind of "DNA testing" would suffice?


Right. So scrap that definition - I lose.


Yes, and horses and donkeys produce mules (or is that horses and mules produce donkeys?). But the mules (or donkeys?) produced cannot themselves reproduce. Can "Ligers"? If not, then I might have to "adjust" my definition slightly - I would consider lions and tigers to be of a different "kind" (but obviously closely related [though not by "descent"]).


Not necessarily (I might have to "adjust" the definition slightly, as in "viable", rather than "viable or not"). They would be a "plant" example of a "mule" (or is that "donkey"?). Unless they can reproduce amongst themselves. Can they?


When you say that "p does NOT hybridize with q", do you mean that it cannot? If so, then that would be an example refuting my idea about "kinds". And, if so, how is it known that this is the case? How many "test cases" have been checked?


I didn't say that they could "naturally" mate. Is it technically possible for a Saint Bernard sperm to impregnate ("fertilize"?) a Tea Cup poodle egg? If so, then they are of the same "kind", according to my definition.


In Christ,

Douglas

DougI

You don't know what asexual means and you are in a debate about biological evolution? Perhaps you should have learned that in elementary school. It would be best if you conceded defeat now.

General Zod

Concede now, before the flames engulf you completely.

faded_Glory

Hey, stop all that talk about conceding defeat! You're ruining my Forum

Seriously, I am reasonably impressed with Douglas so far. There have been very few Creationists (in the year-and-a-half that I have been on the Secweb) that have dared to enter into a formal debate, try to define 'kind', and stayed around to the point in the discussion where the counterexamples forced a re-definition. Douglas is to be commended for still being here!

Douglas' concept of 'kind' is effectively the biological species concept. The numerous observed instances of speciation (see <a href="http://www.talkorigins.org/faqs/faq-speciation.html" target="_blank">here</a>) immediately falsify the statement that one 'kind' cannot produce another, if 'kind' equates to (biological) species.

I suspect that speciation is actually not the type of evolution that Douglas objects to. The evidence for macroevolution in the intuitive sense as 'microbe to man' is not to be found in lab experiments and field observations of speciation. All we can observe in the human timescale are the small-scale changes, including speciation, that over time will result in more and more divergence. Observed speciations are necessary and satisfying support for macroevolution (it is hard to see how there could be macroevolution without microevolution), but more is required. That 'more' is obviously the fossil record - this is where the essential element of time enters the discussion.

Nature as we observe it nowadays is only a two-dimensional time-slice through history. Unless we come up with similar slices at previous times we cannot fully understand the development of life. Macroevolution will not be observed within a single time slice, if we take the thickness of the slice to be just a few thousands years. Anyone who insists that we should is not arguing against evolution but against a strawman.

When investigating the geological record we aim to reconstruct past time slices. There are obviously sampling problems when doing so, and we cannot hope to reconstruct historical time slices with the same resolution as the modern one. Still, the principles of Geology and the massive effort put in over the last couple of hundreds of years by many thousands of geologists have resulted in a reasonable understanding of the Earth' history, so that we can pull out historical slices and get a reasonable impression of what the world looked like at that time (the younger the time slice, the more detail there is). When it comes to building a picture of the living world at that time, we use fossils and Paleontology.

Now, imagine an Earth history where living forms were created as essentially immutable 'kinds'. If we would reconstruct Nature at any particular historical time, what would we see? We would find fossils of animals and plants that in essence look the same as the ones living now. There would be no reason to expect that particular kinds are missing from this record. If we see bears today, we would expect to find fossil bears. If we see lions/tigers/ligers today, we would expect to find fossil lions/tigers/ligers in all past timeslices as well. And so on - everything we see now would always have been there, and there should be no statistically significant different distribution of life forms in the past then there is today.

Is this what we find? Of course it is not. Anyone who claims otherwise is simply dismissing an entire field of science - Paleontology. What paleontologists have demonstrated (back in the 19th century) is that historical time slices contain their own typical fossil assemblages. The further one goes back in time, the more different these assemblages are to the modern living world. This is a fundamental principle that has stood the test of time. With the advent of oil exploration in the 20th century and the corresponding vast increase of subsurface data, this principle has been fully, totally and utterly confirmed (certainly in the microfossil and plant world).

Stratigraphic correlation, oil exploration, and in the final analysis modern society itself, unthinkable without oil, are all the proof you should need to convince you that fossil assemblages change over time.

These then are the building blocks: micro-evolution (speciation) is observed today. Changing fossil assemblages (pretty gradual in the realm of microfossils where oil wells provide so much continouous sampling) show that the living world has profoundly changed over time in a continuous manner. What is missing is a movie record to link the two. Such a movie will unfortunately never exist, but we have the next best thing: our brains, to make the obvious link between the one and the other.

It is only those that feel a need to deny the obvious that continue to do so.

Tell me, Douglas, if you would not believe in a literal Genesis, would you accept that the evidence points to macroevolution?

fG

[ December 08, 2001: Message edited by: faded_Glory ]</p>

RufusAtticus

Seriously, Douglas, you should do a little more digging in science textbooks. DNA testing has been used for decades to determine the similarity of organisms. The early tests were hybridization studies, which measured the similarity of strands of DNA based on how well they matched up or 'hybridized.' More recent tests involve actually sequencing genes from multiple species and determing their relationship. This is how we know that bonobos are our closest relatives. Not from any morphological/behavioral study, but from hard DNA evidence. There is absolutely no honest way to define 'kinds' so that all apes (human included) are not the member of the same 'kind.'

How can organisms or populations be related but not have any common ancestors?

I highly recomend that you read the textbook, "Evolutionary Biology," by Douglas Futyuma and the lighter reading, "The Beak of the Finch," by Jonathan Weiner. You would probably learn alot about Evolutionary Biology in the process, and most of your questions will be answered.

-RvFvS

Douglas J. Bender

rbochnermd,

scigirl said:
(Emphasis mine.)

I replied:
(Emphasis added.)


You responded to my reply:
Notice that scigirl asserted that, as you pointed out, there will be, under the circumstances she mentioned a "struggle" for limited resources. I disagreed with that, but did not argue that there would never be "struggles" for limited resources. You claimed that I denied "...the possibility of a struggle". I did no such thing - I merely denied that limited resources will always result in a "struggle for survival".


I had said:
You replied:
Perhaps; but that was not the assertion scigirl made, and it was not the assertion I disagree with ("The struggle does not have to be 'in all circumstances';..."). Also, I would say that God is involved even in the lives of creatures who are under the curse of sin - so, "natural selection", even in limited circumstances, presupposes that God is not "involved".


I had said:

You responded:
Yes; I probably should have said, "a primary motivating factor sufficient to 'push the limits' of the available resources". Sorry.

In Christ,

Douglas

Quetzal

A slight digression: I've gotta call foul on this one, wonderbread (although I could be easily convinced): Can you show me where someone actually crossed these two critters? Also, was the cross viable in the genetic sense (i.e., capable of reproduction)? If so, is it a new species of Felis, subspecies or what? How's it classified taxonomically?

Inquiring minds want to know.

Richiyaado

Hello Morpho, all,

Tippi Hedren's Shambala Preserve has a liger named Patrick. You can visit their site <a href="http://www.shambala.org/" target="_blank">here.</a>

Once there, type the word 'liger' into their search field and 'Shambala's Patrick Liger' will appear in the list of search results.

According to their information, a 'liger' has a lion father and tiger mother. For a 'tigon', it's vice versa. They also document that a female tigon named Noelle, assumed to be infertile, successfully produced offspring with a male Siberian tiger. The resulting 'ti-tigon' is named Nathaniel.