Re: The Origin of Birds and Their Flight

Stephen Jones (sejones@ibm.net)
Sat, 18 Apr 98 10:58:32 +0800

Reflectorites

It is my contention that the origin of birds from dinosaurs is one of
the strongest possible pieces of evidence for creation by an
Intelligent Designer and the strongest possible evidence against the
dominant Neo-Darwinian `blind watchmaker' fully naturalistic theory
of evolution!

In a nutshell, a line of dinosaurs acquired in advance all the
necessities for powered flight, and when the time was right, the one
animal line on the entire Earth which could benefit from feathers
developed them!

This step-by-step acquisition, in the right animal, at the right
time, in the right order, of all the components for powered flight is
clearly far beyond the power of any plausible "blind watchmaker"
process.

Scientific naturalists think they are describing evolution, but what
they are really describing is a progressive, mediate *creation*!

Here are excerpts from a recent Scientific American article, "The
Origin of Birds and Their Flight". One of the authors, Berkeley's
Kevin Padian is also president of the National Center for Science
Education!

1. Birds are uniquely different from all other animals

"Birds are dramatically different from all other living creatures.
Feathers, toothless beaks, hollow bones, perching feet, wishbones,
deep breastbones and stumplike tailbones are only part of the
combination of skeletal features that no other living animal has in
common with them." (Padian K. & Chiappe L.M., "The Origin of Birds
and Their Flight," Scientific American, Vol. 278, No. 2, February
1998, p29)

2. The key features needed for flight were acquired in advance by a
line of theropod dinosaurs:

"Gauthier's studies and ones conducted more recently demonstrate that
many features traditionally considered "birdlike" actually appeared
before the advent of birds, in their preavian theropod ancestors.
Many of those properties undoubtedly helped their original possessors
to survive as terrestrial dinosaurs*; these same traits and others
were eventually used directly or were transformed to support flight
and an arboreal way of life. The short length of this article does
not allow us to catalogue the many dozens of details that combine to
support the hypothesis that birds evolved from small theropod
dinosaurs, so we will concentrate mainly on those related to the
origin of flight. (Padian & Chiappe, 1998, p33)

* Note the tautology. These "properties undoubtedly helped their
original possessors to survive" because after all....they survived!

3. Some of these key features needed for flight were:

a) Bipedality (for take-off)

"The birdlike characteristics of the theropods that evolved prior to
birds did not appear all at once, and some were present before the
theropods themselves emerged-in the earliest dinosaurs. For
instance, the immediate reptilian ancestor of dinosaurs was already
bipedal and upright in its stance (that is, it basically walked like
a bird), and it was small and carnivorous." (Padian & Chiappe, 1998,
p33)

b) Arms and hands free (to become wings)

"Its hands, in common with those of early birds, were free for
grasping (although the hand still had five digits, not the three
found in all but the most basal theropods and in birds). Also, the
second finger was longest-not the third, as in other reptiles.
(Padian & Chiappe, 1998, p33)

c) Ankles hinged (take-off and landing gear)

"Further, in the ancestors of dinosaurs, the ankle joint had already
become hingelike, and the metatarsal or foot bones, had became
elongated. The metatarsals were held off the ground, so the
immediate relatives of dinosaurs, and dinosaurs themselves, walked on
their toes and put one foot in front of the other, instead of
sprawling. Many of the changes in the feet are thought to have
increased stride length and running speed, a property that would one
day help avian theropods to fly." (Padian & Chiappe, 1998, p33)

d) Lightweight structural members (bone equivalent of aluminium?)

"The earliest theropods had hollow bones and cavities in the skull;
these adjustments lightened the skeleton." (Padian & Chiappe, 1998,
p33)

e) Flight posture assumed beforehand (streamlining)

"They also had a long neck and held their back horizontally, as birds
do today." (Padian & Chiappe, 1998, p33)

f) Fingers reducing (more streamlining)

"In the hand, digits four and five (the equivalent of the pinky and
its neighbor) were already reduced in the first dinosaurs; the fifth
finger was virtually gone. Soon it was completely lost, and the
fourth was reduced to a nubbin. Those reduced fingers disappeared
altogether in tetanuran theropods, and the remaining three (I, II,
III) became fused together sometime after Archaeopteryx evolved."
(Padian & Chiappe, 1998, p33)

g) Hind limbs became more birdlike (more take-off and landing gear)

"In the first theropods, the hind limbs became more birdlike as well.
They were long; the thigh was shorter than the shin, and the fibula,
the bone to the side of the shinbone, was reduced. (In birds today
the toothpicklike bone in the drumstick is all that is left of the
fibula.)" (Padian & Chiappe, 1998, pp33-34)

h) Toes rearranged (for later perching in trees)

"These dinosaurs walked an the three middle toes-the same ones modern
birds use. The fifth toe was shortened and tapered, with no joints,
and the first toe included a shortened metatarsal (with a small joint
and a claw) that projected from the side of the second toe. The
first toe was held higher than the others and had no apparent
function, but it was later put to good use in birds. act the time
Archaeopteryx appeared, that toe had rotated to lie behind the
others. In later birds, it descended to become opposable to the
others and eventually formed an important part of the perching foot."
(Padian & Chiappe, 1998, p34)

i) Shoulder joint rearranged (ready for later wings)

"Through the course of theropod evolution, more features once thought
of as strictly avian emerged. For instance, major changes occurred
in the forelimb and shoulder girdle; these adjustments at first
helped theropods to capture prey and later promoted flight." (Padian
& Chiappe, 1998, p34)

j) Arms lengthened (for later better wings)

"Notably, during theropod evolution, the arms became progressively
longer, except in such giant carnivores as Carnotaurus, Allosaurus
and Tyrannosaurus, in which the forelimbs were relatively small. The
forelimb was about half the length of the hind limb in very early
theropods. By the time Archaeopteryx appeared, the forelimb was
longer than the hind limb, and it grew still more in later birds.
This lengthening in the birds allowed a stronger flight stroke."
(Padian & Chiappe, 1998, p34)

k) Hand & Wrist rearranged (for later better flapping)

"The hand became longer, too, accounting for a progressively greater
proportion of the forelimb, and the wrist underwent dramatic revision
in shape. Basal theropods possessed a flat wristbone (distal carpal)
that overlapped the bases of the first and second bones (metacarpals)
and fingers. In maniraptorans, though, bone assumed a half-moon
shape along the surface that contacted the arm bones. The halfmoon,
or semilunate, shape was very important because it allowed these
animals to flex the wrist sideways in addition to up and down. They
could thus fold the long hand, almost as living birds do. The longer
hand could then be rotated and whipped forward suddenly to snatch
prey." (Padian & Chiappe, 1998, p34)

l) Upper body strengthened (for later powered flight)

"In the shoulder girdle of early theropods, the scapula (shoulder
blade) was long and straplike; the coracoid (which along with the
scapula forms the shoulder joint) wall rounded, and two separate, S-
shaped clavicles conned the shoulder to the sternums or breastbone.
The scapula soon became longer and narrower; the coracoid also
thinned and elongated stretching toward the breastbone. The
clavicles fused at the midline and broadened to form a
boomerang-shaped wishbone. The sternum, which consisted originally
of cartilage, calcified into two fused bony plates in tetanurans.
Together these changes strengthened the skeleton; later this
strengthening was used to reinforce the flight apparatus and support
the flight muscles. The new wishbone, for instance, probably became
an anchor for the muscles that moved the forelimbs, at first during
foraging and then during flight." (Padian & Chiappe, 1998, p34)

m) Pelvis strengthened (for later anchoring of avian lung?*)

"In the pelvis, more vertebrae were added to the hip girdle and the
pubic bone (the pelvic bone that is attached in front of and below
the hip socket) changed its orientation. In the first theropods, as
in most other reptiles, the pubis pointed down and forward, but then
it began to point straight down or backward. Ultimately, in birds
more advanced than Archaeopteryx, it became parallel to the ischium,
the pelvic bone that extends backward from below the hip socket. The
benefits derived from these changes, if any, remain unknown, but the
fact that these features are unique to birds and other maniraptorans
shows their common origin." (Padian & Chiappe, 1998, p34)

* Note: the article does not say this but I have seen it somewhere
that the bird's unique avian lung mechanism needs the bird's unique
pelvis bone as an anchor point.

n) Tail lengthened (for later balance in flying)

"Finally, the tail gradually became shorter and stiffer throughout
theropod history, serving more and more as a balancing organ during
running, somewhat as it does in today's roadrunners. Steven M.
Gatesy of Brown University has demonstrated that this transition in
tail structure paralleled another change in function: the tail
became less and less an anchor for the leg muscles. The pelvis took
over that function, and in maniraptorans the muscle that once drew
back the leg now mainly controlled the tail. In birds that followed
Archaeopteryx, these muscles would be used to adjust the feathered
tail as needed in flight." (Padian & Chiappe, 1998, p34)

o) Even nesting (for later life in trees)

"Evidence for the dinosaurian origin of birds is not confined to the
skeleton. Recent discoveries of nesting sites in Mongolia and
Montana reveal that some reproductive behaviors of birds originated
in nonavian dinosaurs. These theropods did not deposit a large
clutch of eggs all at once, as most other reptiles do. Instead they
filled a nest more gradually, laying one or two eggs at a time,
perhaps over several days, as birds do. Recently skeletons of the
Cretaceous theropod Oviraptor have been found atop nests of eggs; the
dinosaurs were apparently buried while protecting the eggs in very
birdlike fashion. ...Even the structure of the eggshell in theropods
shows features otherwise seen only in bird eggs. The shells consist
of two layers of calcite, one prismatic (crystalline) and one spongy
(more irregular and porous)." (Padian & Chiappe, 1998, pp34-35)

p) And finally, when all was in readiness, the only animal that could
use feathers developed them!

"As one supposedly uniquely avian trait after another has been
identified in nonavian dinosaurs, feathers have continued to stand
out as a prominent feature belonging to birds alone. Some intriguing
evidence, however, hints that even feathers might have predated the
emergence of birds." (Padian & Chiappe, 1998, p35)

To summarise:

"In summary, a great many skeletal features that were once thought of
as uniquely avian innovations-such as light, hollow bones, long arms,
three-fingered hands with a long second finger, a wishbone, a
backward-pointing pelvis, and long hind limbs with a three-toed foot-
were already present in theropods before the evolution of birds.
Those features generally served different uses than they did in birds
and were only later co-opted for flight and fother characteristically
avian functions, eventually including life in the trees." (Padian &
Chiappe, 1998, p34)

The authors think they have been describing evolution, but what they
have been really been staring in the face and describing is in fact
*creation*. The number of genetic changes needed to occur right on
cue, time after time, is nothing short of *miraculous*, as the great
French zoologist P-P. Grasse acknowledged:

"The opportune appearance of mutations permitting animals and plants
to meet their needs seems hard to believe. Yet the Darwinian theory
is even more demanding: a single plant, a single animal would
require thousands and thousands of lucky, appropriate events. Thus,
miracles would become the rule: events with an infinitesimal
probability could not fail to occur...There is no law against day-
dreaming, but science must not indulge in it." (Grasse P.-P.,
"Evolution of Living Organisms," 1977, p103, in Morris H.M.,
"Evolution in Turmoil, 1982, p50)

Steve

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Stephen E (Steve) Jones ,--_|\ sejones@ibm.net
3 Hawker Avenue / Oz \ Steve.Jones@health.wa.gov.au
Warwick 6024 ->*_,--\_/ Phone +61 8 9448 7439
Perth, West Australia v "Test everything." (1Thess 5:21)
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