This is on the edges of my knowledge, so I'm happy to be corrected, but I think the assumption in this text is that the mutant leaps to a whole new species, where as I understand it the evolutionary mechanism is much more gradual, and it's only after many, many generations that the tiny differences mount up enough to lead to speciation - defined as the inability to breed. The Galapagos finches with their adaptations are an interesting case, but I believe they can still interbreed.

The 'no transitional forms' argument, on the other hand, is an old strawman. How would we *know* if any particular creature was 'transitional'? Transition implies a known start and end point, which implies that evolution is teleological, which it's not. Any creature at any stage is just itself...

Actually, this glosses over a fundamental problem in the whole discussion.

You state:

Quote:

---

If an animal mates with another animal not of its exact species, the result will be a sterile

---

Because of the uncertain definition of a species, this statement is not true.

Domestic dogs, canis familiarus, wolves canis lupus , coyotes canis latrans, and foxes (various names), are all different species, but all are interfertile. Although I don't know for certain, the recommended name for the dingo canis lupus dingo indicates it would be, as well.

So, what is a species?

My bio teacher said: Whatever a qualified taxonomist says it is.

But it throws a monkey wrench into the whole debate.

I believe all the Galapagos finches are interfertile, as well, which causes problems.

Quote:

---

Any creature at any stage is just itself...

---

True. But Evolution posits transition. Without transition, there is no evolution to explain origins, only very limited variations.

The Galapagos finches had different morphology, diet, behaviors, etc., but none of them was a turkey. How do we get from firstbird to finch, from firstbird to turkey?

We don't have to know the future (teleology) to ask for transitional forms. Rather, we're asking for an explanation of history.

Re: "If an animal mates with another animal not of its exact species, the result will be a sterile creature . . ."

Sorry Neil, but you are clearly wrong on that point. The term "species" is clearly defined in science. By this I mean that each individual species is clearly defined. [NOTE: in biology, species are what the scientists say the are.] There are many examaples that can be given of cross-fertilization between species, with the offspring being fertle.

If you are going to get into taxonomy, you would be quite correct if you were to say that members of a differing "class" or "order" could not produce fertile offspring. [NOTE: A failure to produce offspring at all is a failure to produce fertile offspring.]

I think that you would be correct if you were to say that members of differing "genera" could not produce fertle offspring. But, under the current, common classification system members of differing species can produce fertle offspring.

Re: "Yet scientific observation reveals that of all the hermaphroditic creatures, only the flatworm is self-fertilizing."

Neil, I believe that you are wrong on this point. But, I will have to do some research to check it out. Later, when I have more time.

I think I can help clear this up.

(1) Species is an ill-defined phrase because of the following problem: Given three populations A,B,C such that any male/female pairing within each population is fertile you can (and do) get situations where all (A,B) pairings are also fertile, all (B,C) pairings are fertile, but no (A,C) pairings are!

Furthermore, even within humans, you can get individual males/females that, when paired, cannot/low-probability-of reproduce but paired with most others would be fertile.

This one fact demolishes almost all the old standard creationist arguments about the fixity of species.

(2) Sexual reproduction goes WAY back - just google "origins of sexual reproduction". Way before there were legs, penises, and vagina...

http://news.nationalgeographic.com/news/2001/07/0709_sexorigin.html

Quote:

---

Claus Wilke of Caltech and Chris Adami, of both Caltech and JPL, have concluded that asexual bacteria can be nudged to evolve into sexual reproduction if they are subject to high levels of mutation induced by environmental stress—from, say, radiation exposure or a catastrophic meteor.

Many primitive single-celled organisms do just fine with asexual reproduction. But mathematical models have demonstrated that a sexual mutant in an asexual population isn't likely to compete successfully and pass on its genes. The researchers say their work shows that higher rates of mutations enable an asexual population to adapt sufficiently to give mutant individuals a greater advantage if those mutants reproduce sexually.

---

http://www.tiscali.co.uk/reference/encyclopaedia/hutchinson/m0007902.html

Quote:

---

Yeasts and a few bacteria may reproduce sexually, although most reproduce asexually.

---

/bevin

Quote:

---

This one fact demolishes almost all the old standard creationist arguments about the fixity of species.

---

While this may not be a straw man, it is outdated enough to be some sort of mulch.

Early (19th century) arguments on this conflated the Biblical "kind" with species. But careful Bible students have long since realized this is making a claim which the Bible itself does not make.

Clearly adaptation produces what might be termed micro-evolution--Darwin's famous finches.

But, as the work--and the controversy over that work-- of Stephen Jay Gould demonstrates, evolutionists themselves are no longer confident of the gradual transitions.

And the "phylogeny recapitulates ontogeny" and even the horse series have long since been abandoned as fanciful.

The problem of defining species undermines evolution as much as creation or intelligent design. It's hard to talk intelligently about anything that cannot be defined, or, as Mortimer Adler pointed out in the case of God, does not at least have a "definite description."

/me just raises his hand to meekly point out that he noted the discrediting of 'phylogeny recapitulates ontogeny' and of evidence from embryology on about p. 3-4 of this thread...

Yes, I remember that you did. But someone else raised it again.

Glad we're on the same page here.

Quote:

---

The problem of defining species undermines evolution as much as creation or intelligent design. It's hard to talk intelligently about anything that cannot be defined, or, as Mortimer Adler pointed out in the case of God, does not at least have a "definite description."

---

*NONE* of the theory of evolution depends on a concept of species. Evolution only requires a large pool of individuals, some of whom can interbreed. Species is simply a quick way to say 'a subset with similar DNA that frequently reproduces within itself'.

One of the possible causes of large changes within a few generations is pieces of DNA transferred from one from one species to another via viruses or similar mechanisms.

/Bevin