MTF
At 01:12 PM 4/24/98 -1000, you wrote:
>I like Mach's observation that perhaps we can use the DNA separation of
>morphologically similar "species" to help us define a group to examine more
>closely for physical differences.
>
>I think that's what he was saying ;-)
>
>Regards,
>Bruce.
>
>Bruce Hansen, ANGFA, caring for our aquatic ecosystems.
>
>Please visit us at http://www.ozemail.com.au/~fisher/angfa.htm
>
>
>
>----------
>> From: Mach T. Fukada <fukada at hawaii.edu>
>> To: rainbowfish at pcug.org.au
>> Subject: Re: [RML] News Flash
>> Date: Friday, 24 April 1998 20:50
>>
>> At 03:36 PM 4/23/98 -1000, you wrote:
>>
>> In fooling around with PCR analysis I recall asking the question as to
>"can
>> it tell me that we are dealing with different species?" I was looking at
>a
>> beetle that some how was able to feed on over 355 different species of
>> plants (many are unrelated plant species). I suspected that there was
>> really a species complex involved and wanted to look into this problem
>via
>> PCR. I was told that there was no criteria set for differentiating
>between
>> species (after all a species is an artificial taxon developed to help us
>> "pidgeon hole" groups of related organisms". I suppose it made sense at
>> least in dealing with insects and differentiating between sympatric
>> populations of the same organisms. There could be radical differences
>> between the two populations genetic make up, yet have no morphological
>> differences. i.e. sweet potato whitefly and silverleaf whitefly. Also
>in
>> cases in which certain insects develop resistance to pesticides, etc can
>be
>> mediated by mutations of the endosymbionts, which would result in huge
>> differences in genetic make up (allozymes, and isozymes also I think),
>but
>> no change in morphology (endosymbiont evolution theory). Now it is
>> possible that there are morphological characteristics that were not
>> considered and as we study further we will find the characteristics that
>> will differentiate these cases where there are very simmilar appearing
>> organisms. However, on the other hand I prefer the ecological approach
>and
>> biological species concept. Of course it might not work in the cases of
>> sympatric species, or are they really species if naturally occuring
>hybrids
>> are formed....
>
>
Mach T. Fukada, Web Master
fukada at hawaii.edu
Honolulu Aquarium Society
http://www.geocities.com/Heartland/Meadows/2948/HASF.html