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"rmacfarl" <rmacfarl@xxxxxxxxxxxxxxxx> wrote in message
news:1121414282.885098.96780@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
>
>
> richardparker01@xxxxxxxxx wrote:
> ...
>> As for the thylacines (I've no idea what sarcophyllus was)
>
> The Tasmanian devil...
>
>> then if it
>> took 4000 years from the arrival of the dingos to wipe them out (the
>> thylacines may be still there) then that's a very slow extinction in
>> our terms.
>>
>> But it's not at all in pre-historical terms, where the statistical
>> error spread on a single date could be at least +/- 4000 years
>>
>> We wiped out the big ones - if we didn't slaughter every one of them,
>> then we certainly messed up the system so much that they couldn't
>> survive.
>
> Yes. The point which works in favour of the blitzkrieg or Future Eaters
> hypothesis a.k.a. Tim Flannery is that where we have well-documented
> recent intrusions by humans onto previously pristine island
> environments, including Madagascar & most of the islands of the
> Pacific, there is very well-attested evidence of disastrous
> consequences for the indigenous fauna.
>
> It's fair enough to postulate that similar effects occurred in
> Australia 50KYA or so ago, but it's also reasonable to question whether
> the early arrivers would have had the ability - perhaps the technology
> - to have a similar impact, especially when initially entering
> Australia on a limited scale in a localised area of what is a bloody
> big bit of terra firma.
>
> I simply don't have the intimate knowledge to know how good the dating
> of Cuddie Springs is, but it is a long way from the only site where
> diprotodonts, giant kangaroos, or other of Australia's lost megafauna
> have been found that's dated to well after the well-documented early
> human arrival dates. Even in the Future Eaters, Tim Flannery refers to
> a site that's dated to less than 20KYA - in other words, nearer in time
> to the present day than the date of first arrival.
>
> So I doubt that humans were pivotal in Australian megafauna extinctions
> - but they undoubtedly were in New Zealand & Madagascar. As to North
> America, I'm unsure. Even if you accept around 16KYA as an arrival date
> - which I think is Meadowcroft's dating - the evidence points to them
> playing a role in megafauna extinction at around 11KYA. But clearly, so
> does climate change, given that's the end of the Ice Age.
>
> I must say I don't buy a 40KYA colonisation of the Americas a la the
> putative footprint trail that's getting an airing in another thread at
> the moment. There would have to be a lot more evidence of long-term
> presence across a wide area, instead of a few controversial sites that
> are dated above 20KYA.
>
> But what would I know?
>
The evidence we already have is that the date constantly gets older while
people claim it can't be true. Shrug. I don't know when they got here but I
do know why old evidence wasn't perceived. The real question is how much
older do we need to look?
> Ross Macfarlane
>
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