Ostrich eggs break dino-to-bird theory
by Jonathan Sarfati
22 August 2002
Subsequently published in
Creation
25(1):34–35, December 2002 – February 2003.
While it’s widely treated as fact that birds evolved from dinosaurs, Genesis
is perfectly clear that dinosaurs—land animals—were created one day
after the birds. And a minority of evolutionists still resist the dino-to-bird theory
on scientific grounds (see Did birds really evolve
from dinosaurs?).
The leader of the evolutionary objections for many years has been Dr Alan Feduccia,
professor and former head of biology at the University of North Carolina at Chapel
Hill, and the author of the encyclopedic The Origin and Evolution of Birds
(1999). He has pointed out many anomalies, e.g. the allegedly birdlike dinosaurs
are ‘dated’ 25–80 million years
after the oldest true bird they are supposed to have evolved into. And
the theropods had curved, serrated teeth while the ‘oldest’ birds such
as Archaeopteryx had straight,
unserrated peg-like teeth. He explains the superficial similarities between birds
and dinosaurs as convergent evolution, i.e. where different groups evolve similar
structures because of a similar lifestyle, in this case walking upright on two hind
legs. Creationists would explain this as evidence of a common designer who designed
similar structures for similar purposes.
Feduccia published a significant
paper in Science1 showing that ‘birds
lack the embryonic thumb that dinosaurs had, suggesting that it is “almost
impossible” for the species to be closely related.’2
We reported on this and other current discoveries in Dino-Bird
Evolution Falls Flat! (1998).3
Now Feduccia and a new Ph.D. graduate, Julie Nowicki, have refined the embryological
study and published their findings in the leading German biological journal Naturwissenschaften.4 They opened a number of ostrich
eggs to examine the embryos at various stages of development. Most studies had concentrated
on embryos in the second half of development, when most of the structures are fully
formed and merely need to grow. But Feduccia and Nowicki found that the main skeletal
features in ostriches, supposedly ‘primitive’ birds, develop between
days 8 and 15 of the 42 days in the egg.
The research conclusively showed that only digits two, three and four (corresponding
to our index, middle and ring fingers) develop in birds. This contrasts with dinosaur
hands that developed from digits one, two and three. Feduccia pointed out:
‘This creates a new problem for those who insist that dinosaurs were ancestors
of modern birds. How can a bird hand, for example, with digits two, three and four
evolve from a dinosaur hand that has only digits one, two and three? That would
be almost impossible.’4
If the birds evolved from dinosaurs, then one would expect common genes. These in
turn would code for a common development in the embryo. But this is not so here,
hence Feduccia is right to argue against the dinosaur-to-bird theory. However, a
common designer is a coherent explanation for the fact that similar structures (in
this case, three-fingered hands) are programmed to develop in totally different
ways.
Diagram showing the difference in developmental patterns of frog and human digits.
Left: In humans, programmed cell death (apoptosis) divides
the ridge into five regions that then develop into digits (fingers and toes) [after
Sadler, T.W., ed., Langman’s Medical Embryology, 7th Ed.,
Williams and Wilkins, Baltimore, Maryland, USA, pp. 154–157, 1995].
Right: In frogs, the digits grow outwards from buds as cells divide
[after Tyler, M.J., Australian Frogs: a natural history, Reed New Holland,
Sydney, Australia, p. 80, 1999].
This is not the only example where superficially homologous structures actually
develop in totally different ways. One of the most commonly argued proofs of evolution
is the pentadactyl limb pattern, i.e. the five-digit limbs found in amphibians,
reptiles, birds and mammals. However, they develop in a completely different manner
in amphibians and the other groups. To illustrate, the human embryo develops a thickening
on the limb tip called the AER (apical ectodermal ridge), then programmed cell death
(apoptosis) divides the AER into five regions that then develop into digits
(fingers and toes). By contrast, in frogs, the digits grow outwards from buds as
cells divide (see diagram, right).
This difference is even more striking than that discovered by Feduccia which he
published in prestigious journals and which he (correctly) used as evidence against
the dino-to-bird theory. So, logically, this huge difference in limb formation should
likewise be regarded as evidence against a common ancestor for humans and amphibians.
In other words, as evidence against the entire evolutionary ‘big picture’.
Wider application: We have often noted that discoveries that supposedly
support evolution are trumpeted throughout the world’s media; but when they
are refuted, even by evolutionists, they are rarely given the same prominence. A
notorious example was the alleged life in the Martian meteorite, now almost universally
discredited as being of non-biological origin.
Similarly, there was almost no publicity of this research by a leading paleo-ornithologist
undermining the dino-to-bird dogma, in contrast to claims in National Geographic
that dino-to-bird evolution was conclusively proven by the new fossil ‘Archaeoraptor’.
But this turned out to be a fraudulent ‘Piltdown
Bird’.
We hope readers of
Creation magazine and this web site will fill this gap by spreading
the true information as widely as possible.
Vestigial digits?
Feduccia’s Naturwissenschaften paper also presented
‘the first concrete evidence for a thumb in birds.’ In ostriches, the
thumb appears around day 14 and disappears around day 17. But in dinosaurs, there
are supposed vestiges of digits four and five in bumps on early dinosaur skeletons.
However, these are not proofs of evolution, and one should be
especially wary about jumping to any conclusion on such a recently discovered phenomenon.
Rather, it’s likely that these ‘vestiges’ are aspects of the program
designed to develop the embryo. At least two possibilities which apply in other
creatures could apply here:
- Sometimes one structure in the embryo is necessary to trigger other structures,
and once the other structures have formed, the first one has done its job and disappears.
For example, the embryos of baleen whales have tooth buds that are later reabsorbed
so the adults have no teeth. However, the teeth have a completely different disposition
in both form and number from those in toothed whales, and have a crucial role in
guiding the developing massive jaw, acting as points on which the developing bone
moulds itself. So it’s possible that the ostrich thumb and extra dinosaur
digits have a role in guiding the hand’s development.
- Another explanation for a ‘vestigial’ organ applies to male nipples.
They are caused by the common embryological plan followed during early embryo development.
Embryos start out producing features common to male and female—again an example
of ‘design economy’. Nipples are a part of this design economy. Similarly,
the vestigial digits could be part of a design economy that modifies one of the
many embryonic development programs that produce the pentadactyl limb pattern. Humans
use this with automobiles, for example. All models might have mounting points for
air conditioning, power steering, etc. although not all have them. Likewise, all
models tend to use the same wiring harness, although not all features are necessarily
implemented in any one model.
References
- Burke, A.C. and Feduccia, A., ‘Developmental Patterns and
the Identification of Homologies in the Avian Hand’, Science
278(5338):666–668, 24 October 1997, with a perspective by Richard
Hinchliffe, ‘The Forward March of the Bird-Dinosaurs Halted?’ on pp.
596–597. Return to text.
- The Cincinnati Enquirer, October 25, 1997.
Return to text.
- See also Oard, M.J., Bird-dinosaur link challenged,
Journal of Creation 12(1):5–7, 1998.
Return to text.
- Feduccia, A. and Nowicki, J.,
The hand of birds revealed by early ostrich embryos, Naturwissenschaften
89:391–393, 2002; Williamson, D.,
Scientist says ostrich study confirms bird ‘hands’ unlike those of dinosaurs,
UNC News Services 425, 26 August 2002.
Return to text.
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