(September 16, 2008 at 8:08 am)FutureAndAHope Wrote: Quote:intermediate transitional forms
This for me is proof of a designer, why? There are no intermediate transitional forms in the fossil record, only whole creatures of varoius kinds.
Also where is the proof of evolution that you said you have. I want to see the evidence.
Don't confuse evolutionary change with development, they are two different things. Many people get that confused. If you are wanting some chimeric creature of sorts, you misunderstand the theory.
I've posted some of this information previously, but I will post it again here. I only ask that if you request evidence and I present it that you will take the time to review and understand it. I provide citations at the end so that anyone may gather further information simply by going to a local library to find those books or journal articles.
Evolution is best thought of as a continuum rather than a jump from key fossil to key fossil. In essence, every fossil that is found represents a “transition” organisms are not static, the populations are always changing over time. And this continuum has many, many branches – not one singular line, hence the analogy of a shrub or a “tree” of life. It is not a singular line, chain or ladder of being (Aristotle’s antiquated
scala naturae idea) of some sort. It is a wildly branching bush:
One need only look at an evolutionary lineage found in the fossil record such as the Chesapecten scallops or trilobites (Pojcta and Springer, 2001). Also, the continual asking for “transitional” specimens can become problematic. If someone asks “where is the fossil to fill in the space between two samples”, and one is presented, then there are now two spaces which “need” to be filled and so on and so forth. It comes close to Zeno’s paradox of the archer and shows the fundamental misunderstanding some hold about this theory.
Now, with regards to the fossil record we can say that we find transitional fossils between two specimens we already have discovered and would expect to find. One excellent example of this was the find of the specimen Tiktaalik roseae.
First is the
T. roseae specimen in a labeled image:
What you see here is dorsal view (b) and a ventral view ©. In the two views the labeling is abbreviated which are the following - an, anocleithrum; bb, basibranchial; co, coracoid; clav, clavicle; clth, cleithrum; cbr, ceratobranchial; ent, entopterygoid; hu, humerus; lep, lepidotrichia; mand, mandible; nar, naris; or, orbit; psp, parasphenoid; ra, radius; suc, supracleithrum; ul, ulna; uln, ulnare. Scale bar equals 5 cm.
More information and pictures of the specimen as well as some pictures of constructed models can be found on a paged dedicated to the find at the University of Chicago’s website –
Tiktaalik roseae: Home
It is an example of a transition in one of the finest senses, not only between two already discovered fossils but one which supports an inferred evolutionary lineage between tetrapods and fish – an evolution which took some 20 million years or so to take place. The find, reported in 2006, shows the morphological traits predicted by evolution in the fish to tetrapods lineage. As noted by Daeschler, Shubin and Jenkins (2006) the fossil's morphological characteristics show, "the body scales, fin rays, lower jaw and palate are comparable to those in more primitive sarcopterygians, the new species also has a shortened skull roof, a modified ear region, a mobile neck, a functional wrist joint, and other features that presage tetrapod conditions." (pp. 757). The organism most likely resided in shallow water habitats where having the ability to move onto land and over sandbars and the like would be advantageous not only for movement but for finding food and possibly mating as well. This discovery fits neatly in between ancient lobed-finned fish and tetrapods.
Another recent find is that of a new specimen of lizard (Adriosaurus microbrachis) which is about 95 million years old. This specimen shows, “complete loss of the manus and zeugopodium in association with elongation of the axial skeleton” (Palci and Caldwell, 2007). The significance of this find would be that it would fit the laymanistic concept of a “transitional” specimen from “lizard” to “snake”.
A similar find was reported in April of 2006 of an Upper Cretaceous serpent with functional hindlimbs as well as a sacrum supporting its pelvic girdle whereas these have been lacking in other specimens which more closely resemble modern snakes (Apesteguia and Zaher, 2006).
This image is of A. microbrachis and shows the pectoral girdle and cervical vertebrae:
This is a drawing of what the specimen would have most likely resembled, notice the reduction in size of the forelimbs – which is also shown in the photograph of the fossil specimen above:
This is a photo take directly from the article on the specimen
N. rionegrina:
These are the images from the research papers themselves and photos of the actual specimens as well.
Also, there is no shortage of specimens showing affinities between theropods and what we would consider those of the class Aves as well. One of the most famous is
Archaeopteryx. It is a link between a type of small dinosaur and modern birds. The morphology of the fossil shows both bird and dinosaur traits. This matter was been hotly debated for many years since its discovery in the late 1800's - was it a dinosaur or a bird? However within the past decade, many other feathered (or with feather-like structures) dinosaurs have been found such as Sinosauropteryx, Protarchaeopteryx, Caudipteryx, Confuciusornis and many others (Chen, Dong, and Zhen, 1998; Ji and Ji, 1997; Hou, Zhou, Martin & Feduccia 1995). A specimen of Archaeopteryx reported in 2005 was an exceptionally preserved fossil which allowed for detailed examination of the morphology. The dinosaurian features it shared with other theropods were a non-avian osteology, hyperextendible second toe like that found in dramaeosaurs as well as no fully reversed toe (Mayr, Pohl and Peters, 2005). This, amongst many other aspects of the specimens of Archaeopteryx solidify its place as an urvogel.
There is also ample evidence to show the link between theropod dinosaurs and the Aves class molecularly. Even experimentation has elucidated much in this area. Researchers examining the Shh (sonic hedgehog gene) expression pattern showed that a small change in the pattern in modern chickens to resemble that found in alligators induces archosaurian teeth to develop (Harris, Hasso, Ferguson and Fallon, 2006).
As far as “transitions” such as this,
there are many that have been documented and are found in the fossil record.
Also, the idea many opponents put forth like “not fully developed” is incorrect. Every organism that reaches developmental maturity is “fully developed”. Using this phrase in talking about evolutionary lineages is just wrong. It views evolution as being progressive toward some predestined goal, it’s not. Those that use such arguments attack evolution and they don’t even understand it.
If you are in need of more evidence, I will do my best to provide it.
References:
Apesteguia, S. and Zaher, H. (2006). A Cretaceous terrestrial snake with robust hindlimbs and a sacrum. Nature, 440, 1037-1040.
Chen, P., Dong, Z., Zhen, S. (1998). An exceptionally well-preserved theropod dinosaur from the Yixian Formation of China. Nature, 391, 147-152.
Daeschler, E., Shubin, N., and Jenkins, F. (2006). A Devonian tetrapod-like fish and the evolution of the tetrapod body plan. Nature, 440, 757-763.
Harris, M., Hasso, S., Ferguson, M. and Fallon, J. (2006). The Development of Archosaurian First-Generation Teeth in a Chicken Mutant. Current Biology, 16, 371-377.
Hou, L., Zhou, Z., Martin, L., and Feduccia, A. (1995). A beaked bird from the Jurassic of China. Nature, 377, 616-618.
Ji, Q. and Ji, S. (1997) A Chinese archaeopterygian, Protarchaeopteryx gen. nov. William Downs (Trans.) Geological Science and Technology (Di Zhi Ke Ji), 238, 38-41.
Mayr, G., Pohl, B. and Peters, S. (2005). A Well-Preserved Archaeopteryx Specimen with Theropod Features. Science, 310, 1483-1486.
Palci, A. and Caldwell, M. (2007). Vestigial forelimbs and axial elongation in a 95 million-year-old non-snake squamate. Journal of Vertebrate Paleontology, 27(1), 1-7.
Pojcta, J. and Springer, D. (2001). Evolution and the Fossil Record. Alexandria: American Geological Institute.