I miss Phil Johnson's posting of articles re new discoveries in
science. Here is an article from New Scientist that caught my eye.
We are told that Archaeopteryx lithographica is a transitional fossil
between reptiles and modern birds.
Much is made of the fact that Archaeopteryx has teeth, rather than a
beak. The problem is that birds with beaks have now been discovered
that may have been near-contemporaneous with Archaeopteryx:
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"It's the early bird that fits the bill"
BIRDS with modern-looking beaks appeared on the evolutionary scene
much earlier than palaeontologists had thought. Beaks were not
supposed to have evolved until 75 million years after Archaeopteryx,
the earliest known bird. Now researchers say that some avian species
had evolved proper beaks just a few million years after Archaeopteryx
made its debut.
In this week's issue of Nature (vol 377, p 616), Lian-hai Hou and
Zhonghe Zhou of the Institute of Vertebrate Palaeontology and
Palaeoanthropology in Beijing and their colleagues describe three
partial skeletons of a bird they call Confuciusornis. The fossils
come from ancient lake sediments near China's border with Korea.
These deposits are difficult to date accurately, but the researchers
believe that Confuciusornis lived about 10 million years after
Archaeopteryx, which appeared around 145 million years ago.
In most respects, Confuciusornis is similar to Archaeopteryx. For
example, its wings bear long claws, which were probably used to
scramble up trees. But unlike Archaeopteryx, Confuciusornis does not
have teeth. "It has a horny bill, just like a modern bird," says
Larry Martin of the University of Kansas in Lawrence, who worked with
the Chinese researchers. The oldest billed bird discovered previously
Gobipteryx, lived in Mongolia about 70 million years ago.
The new discovery suggests that the features we associate with modern
birds have probably evolved and disappeared several times, says
Martin. Some advanced characteristics, such as true bills, evolved
early on in groups that subsequently died out.
The Chinese deposits are still turning up fresh fossils, so further
surprises may be in store. "Our knowledge of the early evolution of
birds is incredibly spotty," agrees Angela Milner, head of vertebrate
palaeontology at the Natural History Museum in London. "We are only
getting the tip of the iceberg."
(Peter Aldhous, "It's the early bird that fits the bill", New
Scientist, 21 October 1995, p19)
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If birds with beaks existed "just a few million years after
Archaeopteryx made its debut", then if evolutionists wish to maintain
that Archaeopteryx is a transitional form between reptiles and birds,
it seems they must postulate either: a) a very rapid transformation
of teeth into a beak; or b) assume that Archaeopteryx dates from
further back in the fossil record.
The problem for evolution with a) is finding a naturalistic
evolutionary mechanism that can transform a full set of teeth into a
beak in "just a few million years". OTOH, the problem with b) is it
might push Archaeopteryx back too far before its putative dinosaur
ancestors, and to where there is no fossil evidence. Of course if it
is supposed that Archaeopteryx existed much earlier than the fossil
record indicates, then one could claim the same for Confuciusornis!
To account for this increasingly complex picture, evolutionists seem
to be increasingly relying the metaphor of a bush. But it seems to be
taking on the shape more of an annual flower bed! :-) Some of their
number are now claiming that "the features we associate with modern
birds have probably evolved and disappeared several times" and that
"some advanced characteristics, such as true bills, evolved early on
in groups that subsequently died out." But this only multiplies the
problems for evolution. It is hard enough explaining how one
transformation occurred, let alone several. Also, if an "advanced
characteristic" such as a beak, was naturally selected because it had
survival value, then "subsequently died out" (presumably because it
had lost survival value), it strains credibility and believe the same
feature was again re-selected because once more it had survival value!
Why couldn't the picture simply be of an abrupt appearance of a wide
variety of true birds, with a wide range of characteristics (some of
which still exist in some birds today), gradually being culled by
natural selection, to produce the narrower variety of birds that exist
today?
Please note that as a Progressive Creationist, I do not necessarily
deny that the bird archetype is a variation on a reptilian theme, but
I am sceptical that a plausible naturalistic evolutionary mechanism
could produce the result in the shortening time available.
Regards.
Stephen
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