>>Again the fossil record provides plenty of examples of change over time, even minor, gradual changes from organism to organism that form a sequence that strongly suggests Darwinian evolution -- even though the idea seems nonsensical to many people. One example is the evolution of the mammalian jaw structure, as seen in the fossil record of mammal-like reptiles called Therapsids that lived before roughly 220 million years ago.<<
The existence of intermediate groups and species seems to be good evidence for evolution. However, the intermediates are not without difficulty for evolutionary theory. First, none of the intermediates have intermediate structures. Although the entire organism is intermediate in structure, it's the combination of structures that is intermediate, not the nature of the structures themselves. Each of these organisms appears to be a fully functional organism full of fully functional structures. Archaeopterx, for example, is thought to be intermediate between reptiles and birds because it has bird structures (e.g.,feathers) and reptile structures (e.g.,teeth, forelimb claws). Yet the teeth, the claws, the feathers and all other known structures of archaeopteryx appear to be fully functional. The teeth seem fully fuctional as teeth, the claws as claws, and the feathers as any flight feathers of modern birds. It is merely the combination of structures that is intermediate, not the structures themselves. Stephen Gould calls the resultant organisms "mosaic forms" or "chimeras." As such they are really no more intermediate than any other member of their group. In fact, there are many such "chimeras" that live today (e.g., the platypus, which lays eggs like a reptile and has hair and produces milk like a mammal). Yet these are not considered transitional forms by evolutionists because they are not found as intermediates in stratigraphic position.
In my opinion an actual transitional form would be something like a creature having a half-leg/half-wing structure. such a half-leg/half-wing structure is absolutely essential because, otherwise, one could always string together a sequence of fossils into a seeming chain of transitions.
Think of it this way: Humans have designed a large number of different types of teaspoons. Some are made of stainless steel, others of silver. Some have monograms on them, others do not. Yet they are all classifiable as teaspoons. And though there are many types of tablespoons, many types of soup spoons and many types of serving spoons, all these types of spoons can be classified together as spoons. The wide variety of spoons can be classified with the wide variety of forks and the wide variety of knives as silverware; and the silverware can be classified with plates, bowls and cups as tableware. Tableware can be classified with furniture and appliances as housewares, and so on. Humans, without so intending, create objects that are distibuted in character space in a nested hierarchy of form. A mere proposed sequence does not tell us if the sequence is the result of intelligent design or random mutations and natural selection. Darwinists presuppose a blind watchmaker, and then impose this hypothesis on the evidence.
When it comes to mammal-like reptiles, these presumed lineages contain such a bewildering array of ostensibly reptilian, mammalian, and unusual traits, that they do not show an unambiguous phylogenetic path to mammals. Therefore, they are best understood as creatures which have a wide and confusing assortment of traits otherwise associated only with reptiles and only with mammals.
As for intermediates, evolutionists can ALWAYS concoct SOME kind of impressive-looking evolutionary sequence. For instance if we, for fun, were to pancake-flip the geologic column upside-down, it would be interesting to see how evolutionists would construct some sort of phylogeny whereby some modern marine invertebrate evolves into a Cambrian trilobite--all the while hailing the sequence as a chain of transitional forms.