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Su Solomon wrote:
> rmacfarl wrote:
> >
> > Su Solomon wrote:
> > > rmacfarl wrote:
> > ...
> > > > But Miller argues that more accurately dated fossils are needed to
> > > > support
> > > > this theory. "The Cuddie Springs dating remains very contentious," he
> > > > says.
> > > > "Most agree that the extinction event occurred between 50,000 and 45,000
> > > > years ago."
> > >
> > > Miller does not give the cites to his claim that the Cuddie Springs
> > > dating is "very" contentious.
> > >
> > > Check out this
> > >
> > > http://www.abc.net.au/rn/science/ss/stories/s1381705.htm
> > >
> > > I find it interesting that the determination, by some people, to
> > > discredit the evidence from Cuddie Springs, borders on the pathological.
> >
> > I can't let that go unchallenged. :-)
>
>
> Pathological?
>
>
> The divide over the dating of Cuddie: is a figment of only a few
> people's fevered imaginations. And those few, like the supporters of
> the RoA are very very vocal.
>
> Just because you keep on saying the same thing over and over again, does
> not make it "real".
>
> Cuddie has a good series of calibrated dates.
I don't dispute that it does (I don't make a habit of disputing that
which I know little or nothing about. :-) I was just suggesting that
pathological" responses aren't confined to 1 side of the debate.
>
> >
> > a) Since the quote from Miller was only in an interview in a Nature
> > article, it's a bit unfair to take him to task over not providing a
> > cite (maybe he did!)
>
> And maybe he didnt : )
But as neither of us know, it seems only fair to grant him the *benefit
of the doubt*.
>
> Besides, dont you find it very strange that ALL of the extinction data,
> and extrapolation that follows, is drawn from a small arid area in
> southern Oz?
>
>
> >
> > b) The Science Show interview you referenced doesn't do much to give
> > the lie to the claim that "The Cuddie Springs dating remains very
> > contentious" because it specifically acknowledges the alternative
> > datings - that was why Field was doing her work there, surely.
>
>
> I was lazy, it was the most recent of Judes talks re Cuddie and the
> 'great megafauna debate' (not forgetting, of course, that a large part
> of the megafauna is alive and well and hopping all over Oz - Megalaeia
> rufa)
When did they take "Big Red" out of genus Macropus?
What M. rufa serves to demonstrate is that the megafauna extinction
within Australia is related to habitat change, because the large
grazers persist while the large browsers have largely disappeared. And
given the extended timeline & the global climate changes over the past
50KYA (& more), this suggests to me that there are no shortages of
environmental factors that would have contributed to species loss in
this period.
To suggest that predation by humans played no part would be silly,
because they obviously would have preyed on the megafauna, as they
continued to do throughout Australia's human history, but to ignore
other factors also makes no sense
>
> > (You
> > may believe that her work has put this issue conclusively to bed, and
> > you may be right, but I'll hazard a guess that not every professional
> > paleoanthropologist in Australia is yet convinced. :-)
>
> Too many axes, or should that be grindstones : ) to grind ; ) ? by
> some may be the answer.
How does that song go? "It cuts both ways..."
>
>
> >
> > c) There is too much tendency on both sides of the debate (hint hint)
> > for pathological or knee-jerk responses. For example, for Field to
> > suggest that because it was rats that the Maoris introduced to NZ that
> > killed the frogs & birds etc, that the New Zealand extinctions were
> > "not a blitzkrieg as such" is just plain silly semantic obfuscation.
>
> The same may be said for Hawaii, what ate the birds there?
I'll apply the same argument as for New Zealand. If the Polynesians
hadn't colonised Hawaii, all those birds wouldn't have gone extinct (at
least until the Europeans arrived to compound the problems. :-)
>
> The big problem Ross, is that it is far too easy, and lazy, to blame one
> factor alone on the complex changes in equally complex environments over
> quite a long span of time, on single factors.
On that we are agreed. But you can apply that argument to early
megafauna extinctions in Australia, because you have "quite a long span
of time". It doesn't apply to NZ & Hawaii.
>
> E.g.: was it solely the introduction of the dingo ca 4000 bp that wiped
> out the thyalcines in 1000 yrs or less, or was it the dingoes AND the
> introduction of a canine disease, and a change in human population
> (upswing), plus increased and intensive hunting by Hss that put the
> thylacines and sarcophyllus out of action on the mainland?
<Gag!> Extinction of thylacines & Tasmanian devils on the mainland
occurred as a direct result of dingos being introduced to Australia, as
a direct result of human intervention. This is exactly the argument
that I take issue with Field over in relation to New Zealand. It's a
human-induced extinction, pure & simple.
Don't lose sight of the difference between proximate causes and
ultimate causes - the immediate cause might be (say) competition for
food from the dingoes, but the ultimate cause is introduction of the
dingoes by humans...
Ross Macfarlane
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