Page 60 - The Origin of Birds and Flight

58 The Origin of Birds and Flight

Reptile bones are heavy, thick and solid. But birds’ bones must be both
strong and light—very thin and hollow, but still strong despite that.
Light, fine bones make it easier for birds to fly, reducing air resistance to
a minimum and reducing the amount of energy needed to take off and
remain aloft.
Although hollow, bird bones are very strong in terms of the power
possessed by birds. For example, the beak of the hawfinch, a bird only
18 centimeters (7-inches) long, can apply 68.5 kilograms (151 pounds) of
pressure to break an olive pit. In contrast to those of terrestrial animals,
the avian skeleton fuses together the shoulder, hip and breast bones. This
lends the bird further solidity. Additionally, this structure reduces the
amount of sinews and tendons to hold the skeleton together, making the
bird even lighter.
As stated earlier, the avian skeleton is lighter than that of all other
vertebrates. A pigeon’s skeleton, for instance, represents only 4.4% of the
bird’s total body weight. A frigate bird’s bones weigh 118 grams (0.260
pounds less than the total weight of its feathers!)
Henry Gee, editor of the scientific magazine Nature, reports this char-
acteristic of birds:

Their breastbones are large, serving as anchors for powerful muscles;
their collarbones are united to form a flexible spring brace . . . Their
backbones are tight, interlocked, and stiff, the interlocking ribs contrib-
uting to a rigid cage, and yet many of the bones are hollow: lightweight
yet strong, like tubular steel. Their pelvis and sacrum are welded togeth-
er into a solid structure. Overall, the body of birds combines lightness
with strength. 40
This anatomy, unique to birds, is completely different from that of
reptiles. Nonetheless, the evolutionary scenario of dinosaur to bird is
still blindly defended, though based on no concrete evidence at all. (We
shall look at detailed instances in due course.)
Certain concepts, being misunderstood, are imagined to represent
evidence for the theory. Based on the differences in dinosaur pelvic
bones, for example, some evolutionist publications suggest that birds