A Full-Fledged Theory
- sharpdb
- 1 hour ago
- 2 min read
Hosts: Doug Sharp and Rich Geer
To gain any credibility, evolutionists need to explain how feathers in birds evolved from reptilian scales. Rather than lining up a handful of fossil impressions such as archaeopteryx, they need to do an analysis of the DNA that produces scales and the DNA that produces feathers. These are totally different designs that won’t convert from one to another, one point mutation at a time. Each mutation must be either viable or neutral, contributing to the health of the organism.
According to Dr. Jerry Bergman, the complex anatomy of a feather varies, depending on the feather’s function. For example, the ‘complex morphology’ of the flight or contour feather includes a long shaft (usually hollow, always strong) and the web that flares out from the shaft in the form of roughly planar vanes on either side. The shaft consists of a hollow, stiff structure (often called a quill or vein) termed the rachis that serves as a solid-but-flexible support for branches called barbs. The rachis and barbs are analogous to tree trunks and tree branches.
Each parallel barb slants diagonally from the shaft and has numerous smaller side branches or barbules (or webs) of different types that overlap those of the neighboring barbs in a herringbone pattern resembling a miniature replica of the whole feather. The flight feather of a large bird can have as many as a million barbules. The barbules in flying birds are held firmly to the next web by ‘hooklets’ called hamuli that function much like Velcro®. These branches and hamuli form a web sufficiently flexible, yet also stiff and dense enough so that when the bird flies, very little air or water can seep through the spaces. The branches and hooklets, in turn, contain barbicles.
The feather barbules also must be strong, yet flexible enough so that they will not break in the wind. Their design enables birds to ride air currents more gracefully than the best glider human engineers have ever designed. If the hooklets are lacking, such as in the plumes of the ostrich, the bird cannot fly. Hooklets are designed so that they can separate under certain conditions, preventing wind damage to the wing and feathers, but can be easily reattached when the bird preens its feathers (ruffled feathers normally prompt preening behavior). Humans can repair a ruffled feather simply by drawing it between their fingers. Preening behavior is part of the irreducible complexity of the total feather design.
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