I wanted to put these thoughts down here in the hopes of provoking an
interesting thread, perhaps encompassing other genuses. Of course all this
below is complete speculation, however:
Of the six falcons found in Australia, the Peregrine is the same species as
the cosmopolitan species, and therefore must be a very recent arrival in
Australia. It's wide occurence in Australia can be attributed to its
peregrinatory nature and the fact that suitable nesting sites can be found
all over Australia.
The Hobby and the Kestrel must be the next most recent arrivals as they are
still closely related to various other Hobbies and Kestrels. They are
widespread in Australia, but their specialised feeding habits perhaps
prevented them from entering into competition with any falcons they might
have found when they arrived.
The Brown, Black and Grey are the descendets of three earlier arrivals, as
none is closely related to any non-Australian falcon (?). Also of the six
they are the most specialised to distinctively Australian habitats,
Grey?arid zone, Black?sub-arid zone, Brown?sub-arid with abundant lizards.
Any thoughts on these propositions?
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Dr John Leonard
PO Box 243, Woden,
ACT 2606, AUSTRALIA
'... after only twenty years in existence much of the
environmental movement has taken on the form of just
another corporation or interest group. Their interest may
be disinterest, but their methods are one with the rational
élites and are therefore limited to the details of corporate life.
[They] ... are attempting to justify restraint and a common-
sense approach to self-respect with the use of intellectual
tools designed to eliminate both.' John Ralston Saul
http://spirit.net.au/~jleonard
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