This paper explores the evidence for design in living systems. In particular, it considers two of the mechanisms used in bird flight. These include feathers and the remarkable counterflow mass exchanger breathing system used in the avian lung system. Both systems are examples of the principle of specified functional complexity, which occurs throughout nature. There is no known recorded example of this developing experimentally where the precursor information or machinery is not already present in embryonic form. Such design features indicate non-evolutionary features being involved.
avian respiration, birds, design, evolution, feathers, lungs, nature
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