[Continued from part 1/2]
Birds' unique respiratory system is a preadaptation
These results indicate that birds' unique respiratory system, which enables them to meet the metabolic demands of high altitude flight, developed well before birds themselves arose. This Majungatholus atopus fossil is dated at 67 million years ago, but the first undisputed fossil bird, Archaeopteryx, is dated at 145 million years ago.
That is, the unique avian respiratory system is a preadaptation, a structure adapted to an earlier environment that was later found to be advantageous in a very different environment. In this case a respiratory system in a line of terrestrial dinosaurs was found to be advantageous, indeed essential, for the high altitude flight that only birds are capable of. However, evolutionists these days don't like the term "preadaptation" because it has "overtones of 'foresight'" and has "teleological implications", so in the past 20 years have they increasingly used the term exaptation, meaning "useful as a consequence of.".
The avian `flying kit: a `construction project' design argument
However, when one considers all the preadaptations (using the original term) that `just happened' to have occurred in the non-flying dinosaur ancestors of birds, amounting to an avian "flying kit," including feathers, furcula (wishbone), keeled sternum (breastbone), hand of three fused fingers, pygostyle (fused tail vertebrae), shoulder joint allowing up, forward and down strokes, folding forelimb, highly efficient respiratory system, hollow bones, hallux (reversed rear claw) and nesting, together they have the hallmarks of a `construction project' carried out by an Intelligent Designer (who I assume to be the Christian God), towards a long-term goal.
This avian `flying kit' is only one of a number of such `construction projects' (for example, the amniotic egg; the mammalian ear; and the `human package') which together will form part of my "`Construction Project' Argument from Design" in my future book, "The Design Argument."
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