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- Newsgroups: sci.environment
- Path: sparky!uunet!newsgate.watson.ibm.com!yktnews!admin!mothra6!andrewt
- From: andrewt@watson.ibm.com (Andrew Taylor)
- Subject: Re: Population growth and cultural destruction (Re: Nast
- Sender: news@watson.ibm.com (NNTP News Poster)
- Message-ID: <1992Dec30.192317.1676@watson.ibm.com>
- Date: Wed, 30 Dec 1992 19:23:17 GMT
- Disclaimer: This posting represents the poster's views, not necessarily those of IBM
- References: <1992Dec30.010943.5088@watson.ibm.com> <725702732snx@tillage.DIALix.oz.au>
- Nntp-Posting-Host: mothra6.watson.ibm.com
- Organization: IBM T.J. Watson Research Center
- Lines: 67
-
- In article <725702732snx@tillage.DIALix.oz.au> gil@tillage.DIALix.oz.au (Gil Hardwick) writes:
- >Please do cite just one occasion where I have insisted exclusively on
- >graduate qualifications to post here?
-
- Message-ID: <724469845snx@tillage.DIALix.oz.au>
- >The *minimum* entry requirement should be graduate level, while the
- >rest get on with mastering the undergraduate basics. Or qualifying for
- >fresher entry to start with would help . . .
-
- >The issue throughout has been on the standard of debate, expecting that
- >people do at least some level of homework before engaging in reasoned and
- >thoughtful argument on any matter concerning the environment.
-
- But you don't do this. For example, you posted that quolls are extinct.
- Not only are there several extant species but one is found not far from where
- you live. Your knowledge of Zimbabwe apparently doesn't even extend to its
- location. But when I point out your many errors, the response is another
- 20 lines of blather, unblemished by any knowledge of Zimbabwe.
-
- >I am far more interested in your reasons for selecting this one among
- >very many indeed, and reposting it now after no other response to it
- >was forthcoming whatever.
-
- Actually I responded at the time but our news machine apparently did not
- transmit it. Here is another response to you which was apparently also lost.
-
- > I have mentioned here before that it is the very small species rapidly
- > becoming extinct . . .
-
- You claimed this here before about Australian mammals and I explained to you
- why it wasn't true. You responded saying you were ignoring me because I wasn't
- an Australian citizen (I am). Let me try again.
-
- Although there have been a few extinctions among Australia's small mammals,
- mainly hopping-mice with small ranges, they have been relatively unscathed.
- It is largely medium-size mammals that have affected. From memory the critical
- size range is 0.5 to 10kg.
-
- One theory is that rabbits overwhelmed and destroyed the drought refuges
- that these mammals depended on. Sufficent fragments remained to support the
- small mammals and the large mammals did not depend on the refuges. It is also
- likely that mammals in this range were more vulnerable to fox predation.
- Tim Flannery's Australia's Vanishing Mammals should discuss all this.
-
- [In response to an example of an inverted biomass pyramid from Alan McGowen]
- > Alan, you forgot the case of land reptiles (water pythons) which live
- > off small land mammals (swamp plain rats) as their respective life-
- > cycles replicate those of whales and krill, for example.
-
- Last I heard, there wasn't a good estimate of the density of the Flood Plain Rat
- (R. colletti)'s density. The indications are it is extremely abundant.
- Do you have any reference/source/basis for the claim that the Water Python's
- biomass exceeds its prey
-
- > cold-blooded reptiles just hybernate on it without feeding for extended
- > periods over years while populations of the former wax and wane.
-
- Reptiles do not hibernate, they may become torpid. I doubt Water Pythons
- much of that either. I doubt even more that they spend years without feeding.
-
- > A high turnover, BTW, does not equate with high productivity,
-
- How can a high turnover not correspond with a high productivity?
- Surely the replacement of lost individuals requires high productivity at
- least at the species level.
-
- Andrew Taylor
-