THE CURSORIAL THEORY AND NATURAL SELECTION
The idea that dinosaurs turned into birds by growing wings as they hunted flies is not a comic story, but in fact, evolutionist theoreticians' most serious thesis regarding the origin of birds.
This is one of the two main explanations proposed by evolutionists as to how terrestrial reptiles began to fly. According to this theory, reptiles took to the air vertically, by hopping from the ground. The basic concept is that certain reptiles flapped their forearms very rapidly and for long periods as they chased insects, and that over the course of time, these forelegs developed into wings. Not the slightest explanation is offered, however, for how such a complex structure as a wing could have come into existence from forearms being beaten against one another in order to trap flies.
John Ostrom, a prominent adherent of the cursorial theory, admits that the proponents of both hypotheses can do no more than speculate: "My cursorial predator theory is in fact speculative. But the arboreal theory is also similarly speculative." 1 (See Arboreal Theory, the.)
Even if we assume that mutations did cause undirected changes in a reptile's forearms, it is still irrational to expect that any wing could emerge by chance through the addition of cumulative mutations. Any incremental mutation taking place in its forearms would not endow the reptile with functional wings, but would leave it deprived of functioning forearms. This would leave the animal disadvantaged (in other words, defective) compared to other members of its species. According to the rules of the theory of evolution, that deformed creature would be eliminated through natural selection.
Evolutionists' intermediate-form dilemma also applies to the origin of birds. According to evolutionist claims, semi-winged or partly-winged reptiles should have existed before birds. Yet had such creatures existed, the fossil record should confirm this. Yet these heroes of evolutionist scenarios are no more than imaginary reconstructions, based on no hard scientific evidence.
(1) A dinosaur, many of which we see in the fossil record.
(2,3,4) There is not the slightest evidence that any such semi-developed creatures ever existed.
(5) A fully-fledged bird, of which we see many specimens today.