Wingtip Path Coherence Previously Not Thought Possible
When aircraft fly the air pressure on the underside of the wing is greater than on the topside. This pressure difference provides the needed lift force on the wings. It also causes the air at the end of the wing to move upward and then around in a circle, resulting in a strong vortex that trails the wing tips as the aircraft flies (see photo). Birds also have trailing vortices but they are far more complex given the complicated shape of the wing and the bird’s flapping motion. And so while it is tempting to think that the familiar V-formation used by migrating birds is for aerodynamic efficiency, evolutionists have long since been skeptical because of the tremendous precision that would be required for birds to take advantage of the complicated aerodynamic environment. Perhaps, evolutionists thought, the formations were used simply to follow leader, or for protection from predators. But a fantastic new study—using miniature sensor packages consisting of a satellite GPS receiver and accelerometers—has demonstrated that birds do indeed track their aerodynamic environment in real-time and take advantage of it with precise positioning and wing flapping:Here we show that individuals of northern bald ibises (Geronticus eremita) flying in a V flock position themselves in aerodynamically optimum positions, in that they agree with theoretical aerodynamic predictions. Furthermore, we demonstrate that birds show wingtip path coherence when flying in V positions, flapping spatially in phase and thus enabling upwash capture to be maximized throughout the entire flap cycle. In contrast, when birds fly immediately behind another bird—in a streamwise position—there is no wingtip path coherence; the wing-beats are in spatial anti-phase. This could potentially reduce the adverse effects of downwash for the following bird. These aerodynamic accomplishments were previously not thought possible for birds because of the complex flight dynamics and sensory feedback that would be required to perform such a feat. We conclude that the intricate mechanisms involved in V formation flight indicate awareness of the spatial wake structures of nearby flock-mates, and remarkable ability either to sense or predict it. We suggest that birds in V formation have phasing strategies to cope with the dynamic wakes produced by flapping wings.
Here is how one science writer summarized the study:
To take maximum advantage of the V’s aerodynamics, each bird would have to position its wing in the upward-moving part of the vortex of air swirling off the end of the wingtip of the bird in front. But that vortex moves up and down because the bird in front is flapping. So the bird behind must not only put itself in the right place, but must also flap at just the right time — which changes depending on the distance between the birds — to keep riding the upwash. Faced with this complexity, scientists posited alternative reasons for the formation, suggesting that it might protect the birds against predators or let a flock put better navigators up front.
Not only does this formation flying capability falsify evolutionary expectations, its origin is not explained by evolutionary theory. In fact, without the trailing bird’s ability to track the dynamic wake structures of the leading bird, process that information, and precisely adjust its position and its wing flapping, the formation flying could be worse than simply flying alone. To gain the advantage all these capabilities must be in place and coordinated with each other. So with evolution we must believe that all these capabilities somehow evolved from chance mutations and worked together, so they could then be selected. There are just far too many mutations required before the increased fitness is realized and the probability of evolution creating formation flying capability is tiny.
When Darwin proposed his theory of evolution, a century and a half ago, it seemed unlikely. But ignorance of biology’s details provided cover. Now that cover is gone. Ever since Darwin those details have slowly come to light and one after the other have confirmed the absurdity of evolution.
Religion drives science, and it matters.











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