>From the linked wiki "sometimes referred to by its German name Urvogel ("original bird" or "first bird")"
Martin
On Tue, Aug 2, 2011 at 2:25 PM, Philip Veerman <> wrote:
Curious. That implies that what has happened in prehistory is
strangely somehow influenced by what someone believes. It is hard to imagine how
the nature of a person's thought process in the 21 century could maybe change
what has happened.
What
if I believe in the rainbow serpent or that geese change into barnacles every
year? The idea that they were
all created at exactly the same instant is only one of many culturally
induced suggestions (not the only alternative automatic to evolution as Martin
suggests) and no reason to think that one is any better than others. Sadly for
that idea, there is nothing in the fossil record consistent with the idea that
they were all created at
exactly the same instant.
Another idea is that if dinosaurs were alive today, that birds would
simply be classified as another order within the class of vertebrates, most of
which are dinosaurs and the difference between them is really not so great.
Because birds are mostly comparatively small and delicate, there are not many
fossils showing that important period. As more fossils are found, we may
understand the process better and the dividing line will become harder to
place.
I
wonder what Urvogel
means, certainly vogel (in German & Dutch) simply means bird but what
does ur mean? Is it a precursor of that awful brand of lazy grammar horror of
kids' SMS text speak for "you are"? As in "You are bird"?
Of
course Archaeopteryx is ancient wing and
not an English word.
Philip
-----Original Message-----
From: martin butterfield
[
Sent: Tuesday, 2 August 2011 8:09
AM
To: Tony Lawson
Cc: Canberra Birds
Subject: Re:
[canberrabirds] "First Bird" Fossil, Archaeopteryx, More Closely Related to
Dinosaurs
Tony asked "What is now the first bird?".
I have two answers to this. If one believes that evolution
is an analogue process with many infinitesimally small differences over small
periods of time the answer is "unknowable". As long as palaeontologists
are promoted on the basis of number of published papers there will always be
debate as to exactly where to draw the line defining where something ceased to
be a dinosaur and became a bird. On the other hand if one doesn't
believe in evolution the answer is "All of them" as they were all created at
exactly the same instant. It is interesting to read http://en.wikipedia.org/wiki/Archaeopteryx.
There appear to have been only 11 fossils of Archaeopteryx ever found, so the
sample sizes are not great! (Incidentally this must be one of the very few
cases in which a German name - Urvogel - is shorter and easier to spell than the
usual name in English.) Martin
On Tue, Aug 2, 2011 at 7:41 AM, Tony Lawson <>
wrote:
Yet another account - if you'r not sick of them by now -
& Geoffrey, in my view it reads pretty well.
But what now is the
first bird?
Tony
"First Bird" Fossil, Archaeopteryx, More Closely
Related to Dinosaurs
| July 27, 2011 | 2
By Matt Kaplan of
Nature magazine
Analysis of fossil traits suggests that
Archaeopteryx is not a bird at all. The latest discovery of a fossil that
treads the line between birds and non-avian dinosaurs is leading
paleontologists to reassess the creature that has been considered the
evolutionary link between the two.
Archaeopteryx has long been
placed at the base of the bird evolutionary tree. It has traits that have
helped to define what it is to be a bird, such as long and robust forelimbs.
Yet in recent years, the discoveries of numerous small, feathery dinosaurs
have created a conundrum for paleontologists, raising questions about which
animals are the ancestors of modern birds and which are just closely related
cousins.
The fossil that is driving the latest Archaeopteryx
rethink is called Xiaotingia zhengi, and is described in Nature today by Xing
Xu , a paleontologist at the Institute of Vertebrate Paleontology and
Paleoanthropology in Beijing, and his colleagues. It was found in western
Liaoning, China, in rocks dating to the Late Jurassic epoch, 161 million-145
million years ago. Like many similar fossils, it is surrounded by feather
impressions in the rock, but has claws on the ends of its forelimbs and sharp
teeth.
These traits by themselves do little to help place the
fossil in the dinosaur-bird transition, but Xu reports that it also has
extremely long middle and last finger bones and a wishbone with an L-shaped
cross-section at one end. These characteristics, Xu argues, identify
Xiaotingia as very closely related to Archaeopteryx and another feathery
relative, Anchiornis.
After analyzing the traits present in
Xiaotingia and its relations, Xu and his colleagues are suggesting that the
creatures bear more resemblance to the dinosaurs Velociraptor and Microraptor
than to early birds, and so belong in the dinosaur group Deinonychosauria
rather than in the bird group, Avialae. Many features led the team to this
decision, but the most immediately noticeable are that Xiaotingia,
Archaeopteryx and Anchiornis have shallow snouts and expanded regions behind
their eye sockets. Microraptor has similar traits, but the early birds in
Avialae have very different skulls.
Out of first place
The
first Archaeopteryx specimen was discovered in 1861, just a few years after
the publication of Charles Darwin's On the Origin of Species . Its combination
of lizard-like and avian features made it the ideal 'missing link'; with which
to demonstrate evolution from non-avian dinosaurs to birds. But the latest
rearrangement knocks it from its position as the earliest bird. "I think
Archaeopteryx's placement was the result of both history and relatively poor
sampling at the dinosaur-bird transition," explains Xu.
Even so, he
acknowledges that the move is bold. "Because it has held the position as the
most primitive bird for such a long time, I am kind of nervous about
presenting this result," says Xu. But immediate responses from others in the
field suggest that the decision will be widely
embraced.
Archaeopteryx was a bird because it had feathers and
nothing else had them. But then other animals started being found that had
wishbones, three-fingered hands and feathers. Heck, even T. rex had a
wishbone. So one by one we've learned Archaeopteryx's uniquely avian traits
weren't so unique. The writing was really on the wall," says Lawrence Witmer,
a paleontologist at Ohio University in Athens.
Whether this change
will be permanent depends on what other animals are discovered in the future,
says Thomas Holtz , a paleontologist at the University of Maryland in College
Park. "I don't think this is going to be the last word on this subject. You
take this new Chinese species out of the mix and the argument falls apart, so
the new placement is precarious at best until further evidence is dug
up."
This article is reproduced with permission from the magazine
Nature. The article was first published on July 27, 2011.
http://www.scientificamerican.com/article.cfm?id=first-bird-fossil%2C-archaeopter&WT.mc_id=SA_CAT_EVO_20110801
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