"Native Australian budgerigars are blue in colour"

To: Birding Aus <>
Subject: "Native Australian budgerigars are blue in colour"
From: Andrew Hobbs <>
Date: Tue, 27 Feb 2007 17:16:29 +0900
I don't know about the accuracy of the rest of the book but I would take
issue with the examples as given.

The authors of this current text actually make many false statements.
Just one more example relating to birds follows.

They claim that “the fossil record also gives evidence that species
have changed over time, and may show how new species arose.”  They use
Archaeopteryx as an example and claim that its morphology has allowed
scientists to deduce “that birds have evolved from a dinosaur ancestor.”

Well for a book published in 2000 the authors should have taken notice
of many science writers over previous years, before they chose their
example.  These two statements - published well before this text are
examples of literature that could have helped prevent them from making
this error.
There have been a few other discoveries indicating that the story of the
evolution of birds is at least somewhat more complicated than a simple
transition from dinosaurs - Archaeopteryx - birds.  However
Archaeopteryx is still regarded as a potential intermediate form between
the theropod dinosaurs and early true birds.

“We are not even authorised to consider the exceptional case of the
       Archaeopteryx  as a true link. …An animal displaying characters
       to two different groups cannot be treated as a true link as
long as the
       intermediary stages have not been found, and as long as the
       mechanisms of transition remain unknown.”  P.L. du Nouy.  Human
Destiny. NY. 1947.
This of couse is a circular argument. If you are not prepared to
entertain the notion of an intermediate group as being an evolutionary
link until intermediary forms are found you will never get anywhere.
For example what if you find another form which is intermediate between
Archaeopterix and modern birds.  You could not accept it as a link since
you don't have the intermediate forms.  Ad infinitum.

In any case intermediate forms have been found, at least between
dinosaurs and Archaeopterix.  That is several fossil remains of theropod
dinosaurs show a distinct coating of feathers.  Indeed several
taxonomists have suggested that perhaps all theropod dinosaurs may have
had feathers.

Bird footprints are more common in Mesozoic sediments than is generally
       recognised …. Those in the lower Cretaceous and Jurassic are
       stratigraphically lower than Archaeopteryx   and therefore are
       evidence that Archaeopteryx  is not the ancestor of modern birds.
                   Lockley, M.G., S.Y. Yang, M. Matsukawa, F. Fleming
& S.K. Lim. 1992. The Track Records of
                   Mesozoic birds: Evidence and implications.   Phil.
Trans. Roy. Soc. Lond. B 336: 113-134.

There has been considerable discussion on the scientific literature
about such footprints but the concensus now seems to be that they were
not bird footprints, but may have been a type of theropod.

So I think it is clear we need to teach our youngsters to challenge
everything they hear and read, and to look widely and thoroughly
before making concrete statements relating to science.  Part of
looking widely could be learning something about birds.
Can't argue with this.  If they always question they might turn into
halfway decent scientists.



Happy birding and thinking.

Oh yes if you have seen any swifts lately please let me know TIA.

Mike Tarburton


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