[Taxacom] Hedges /Kumar (eds) The Timetree of Life

[Frederick W. Schueler]

On 5/18/2011 8:55 PM, Robin Leech wrote:

> If we find evidence that the particular species WAS there, even for a short time, then we have to invoke # 1if the species
> is not there today.
> So, circling in on my own logic, if a species that was there, established, and is now gone (extinct), can I invoke # 1 again?
> Surely, if it was there and does not carry on indefinitely, then it has to be # 1.
>
> But then we have to try to figure out the reason it could not live there: summer too short; winter too long; one or more essential
> minerals or protein precursors not there; predators; parasites; and the list grows.

* and then there's the question of what it means that a "species" could 
abstractly live on a site, in contrast to whether the 
individuals/population that happened to have been there could/can 
persist or increase on the site (cf Ken's discussion of inbreeding).

fred.
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          Frederick W. Schueler & Aleta Karstad
Bishops Mills Natural History Centre - http://pinicola.ca/bmnhc.htm
now in the field on the Thirty Years Later Expedition -
http://fragileinheritance.org/projects/thirty/thirtyintro.htm
Daily Paintings - http://karstaddailypaintings.blogspot.com/
     RR#2 Bishops Mills, Ontario, Canada K0G 1T0
   on the Smiths Falls Limestone Plain 44* 52'N 75* 42'W
    (613)258-3107 <bckcdb at istar.ca> http://pinicola.ca/
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