Grammar

Mike, This is a misrepresentation. To illustrate, can you show me a fossil species of starfish from the Mesozoic that is alive today? What about a frog, or shark even? What about the creationist staple, the coelacanth? In truth there are coelacanth fossils, but not the living ones today. In fact Latimeria chalumnae has an extra pair of ventral fins plus a double tail. An analogy would be creationists of 70 million years in the future saying that our four legged cow is identical to their six legged bovines!This question needs tackling on two levels, firstly, I assume you are generally familiar with the classification system? As you probably know, it is a heirarchical system that has big groups full of smaller & smaller subsets. Take frogs, for example. They belong to Order Anura (along with toads). An Order is a fairly high level taxa, the equivalent to Therapsida, containing monsters such as T.Rex, Velociraptor, Allosaurus, etc. Or the Primates, containing mammals as diverse as humans, bush babies, lemurs, & marmosets, for example. Now, the higher the level of taxa, the longer you can expect members of that taxa to have hung around, since a high level taxa has MANY smaller taxonomic levels within it, & therefore has a greater taxonomic survivability than smaller taxa. Order Anura contains families, genus', & species. What could we reasonably expect of the pattern of survivability of different taxonomic levels, then? Families are the larger of the taxonomic scales (that contain genus' & species), so we could reasonably expect fossil members of Anuran families to go back further than the genus or species level. That is what we see. There isn't a single genus or species living today that is represented in the Mesozoic (251-65 mya), yet families are. So to say frogs are found unchanged in the fossil record is disingenuous. The further you go back the more basal Order Anura becomes, which is by itself strong evidence of evolution. In fact this is a trend in the fossil record. Creationists always claim that taxa appear with no precursors (with justification), yet fail to take into account that when they do appear, they are very primitive versions of what they eventually become. Take Order Carnivora, for example, containing the canines & felines. Today it's fairly easy to tell any one canine skeleton from any one feline. The further you go back, however, the features that makes felines felines, & canines canines become more & more less pronounced. But I digress....To put it another way, Order Anura may survive, but many smaller sub-groups do not, & are even replaced by newly evolving organisms that are different enough to be placed in a new genus, yet are still frogs or toads by definition!!Secondly, why would an organism change in morphology over time? Very simply, because their environment does. Imagine an organism that isn't well adapted to it's environment. It will suffer as many (roughly) mutations as an organism that is well adapted to it's environment. The difference being that all mutations that affect the well adapted organism will be deleterious (because they upset the optimal morphology/chemistry), but the substandard organism is going to get some of it's mutations be beneficial (because there is room for improvement). There come a point where our maladapted organism becomes well adapted, & any further mutations are selected against. This is called stabilising selection. Hence, if an environment doesn't change appreciably as far as our organism is concerned, it will remain in "stasis".Hope this helped.Mark------------------
Occam's razor is not for shaving with.

Mike, Yes, it suggests divergence from a common ancestor. Yes, it's a bit more complicated than that, but is generally true. Organisms may show habitat loyalty, ie. they move to an environment that is what they are comfortable with, rather than staying in a changing environment, thus doing away with the necessity of that nasty evolution business. Furthermore, there is neutral drift, sexual selection etc. to take account of, which is why it's so hard to stop real change, but the basic body plans of various taxa are easily preserved, in the same way a peacock has evolved so much by sexual selection, (but is still a member of Class Aves) rather than natural selection (strictly speaking), it's natural habitat probably hasn't changed much at all. But if the girly birds want a bigger fan tail, then that's what will be selected for!Mark------------------
Occam's razor is not for shaving with.

Mike, What you are describing are intermedate & transitional fossils. I had a looked up a site which had some great photos of the reptile-mammal transition, but my computer froze & I couldn't find the same site after that. grrrr. Anyway, this graphic shows the essence of what was in my lost url. This particularly shows the transition from a reptilian middle ear to a mammalian one, your hammer anvil & stirrup. "Figure 1.4.3. A comparison of the jawbones and ear-bones of several transitional forms in the evolution of mammals. Approximate stratigraphic ranges of the various taxa are indicated at the far left (more recent on top). The left column of jawbones shows the view of the left jawbone from the inside of the mouth. The right column is the view of the right jawbone from the right side (outside of the skull). As in Figure 1.4.1, the quadrate (mammalian anvil or incus) is in turquoise, the articular (mammalian hammer or malleus) is in yellow, and the angular (mammalian tympanic annulus) is in pink. For clarity, the teeth are not shown, and the squamosal upper jawbone is omitted (it replaces the quadrate in the mammalian jaw joint, and forms part of the jaw joint in advanced cynodonts and Morganucodon). Q = quadrate, Ar = articular, An = angular, I = incus (anvil), Ma = malleus (hammer), Ty = tympanic annulus, D = dentary. (Reproduced from Kardong 2002, pp. 274, with permission from the publisher, Copyright 2002 McGraw-Hill)"With exceptions, the fossil record is generally too patchy to get a slow transitional series between one taxa & another. The reptiles to mammals are an exception. I don't think cetaceans (whales) are tooooo bad, nor are the fish-tetrapods.That said, there are other intermediate fossils like Archaeopteryx lithographica which are clearly part way between reptiles & birds.Mark------------------
Occam's razor is not for shaving with.

Mike, What about this fantastic concordance between dating methods?Why such agreement between dating methods with different isotopes? Do you really ascribe such things to coincidence?Mark

Mike, Well, there's a data filled retort!Your creation scientists don't use rulers to measure things. They are too prone to human error, I myself have made a mistake using a ruler & certainly won't be using one again. I will of course ignore the vast number of corroborating results made with rulers & declare them unfit for their intended use against all evidence to the contrary on the basis of a few poor results.Sound familiar, anyone?If you try to answer these questions in here, Mike, you'll see you have been spun a yarn just as big the "why-you-should-not-use-a-ruler" ruse, above. What about this fantastic concordance between dating methods?Good luck!Mark------------------
Occam's razor is not for shaving with.

Mike, The point being, Mikey, my boy, is that you swept away Schrafs comments with absolutely jack shit. You didn't attempt to respond, your answer was essentially, "well, there are cleverer people than me who disagree with you"!!!Not very convincing.For the third time: What about this fantastic concordance between dating methods?Yours, & the creationist position in general is untenable if it cannot respond to corroborative data such as this. Buzsaw has ejected from his third thread because of his inability to deal with contradictory evidence. Question is, are you going to ignore it & pretend it isn't there like he did, or are you going to factor it into your thinking?I've put a lot of thought & time into providing responses for you earlier in this thread, it's only fair you respond in kind. It's what debate is about, after all.Mark------------------
Occam's razor is not for shaving with.[This message has been edited by mark24, 07-22-2003]

Mike, John Mackay isn't an expert on radiometric dating, & Brent Dalrymple is. So why don't you ignore Mr Mackay for a moment, & address this (by Mr Dalrymple): What about this fantastic concordance between dating methods?I'm beginning to think you're evading the issue. Is your role here to simply tell me to ask your favourite people my questions? No, Mike, you are here, you claimed, to learn. So why don't you adress the issues? It seems to me that you can't do a lot of "learning" when your response to any awkward question is to tell them to ask someone else. What gives?I have answered all your questions, thus far. Now it's your turn, or are you reaching for the ejector seat handle like Buzzsaw?Mark------------------
Occam's razor is not for shaving with.