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

[John Grehan]

Extinction is as much a part of the data for panbiogeography as the living. Living and fossil taxa can be tracked together and the fossils, when present, help fill in the 'gaps' among the living. A recent example from my work is where humans and orangutans appeared to be disjunct between Africa and South East Asia, but are less so when the 'gap' is filled in with Hispanopithecus, Ankarapithecus, Ouranopithecus, Sivapithecus, Gigantopithecus, Khoratpithecus etc. Of course there are always 'gaps' which is why one needs tracks to identify spatial relationships.
 
John Grehan

________________________________

From: taxacom-bounces at mailman.nhm.ku.edu on behalf of Richard Pyle
Sent: Wed 5/18/2011 10:58 PM
To: 'Robin Leech'; 'Dick Jensen'
Cc: 'Taxacom'
Subject: Re: [Taxacom] Hedges /Kumar (eds) The Timetree of Life



> 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.

I disagree.  That a species does not live somewhere, where it once lived in the past, does not mean it *cannot* live there now.  It only means that it failed (for whatever reason) when it was there before.  Perhaps it failed because conditions are such that it cannot live there; but it may also have failed as a result of anomalous circumstances  that no longer apply (e.g., unusual climate conditions, catastrophic event, predator that has also gone extinct; prey that went extinct but has since become re-established, etc.).

Aloha,
Rich



_______________________________________________

Taxacom Mailing List
Taxacom at mailman.nhm.ku.edu
http://mailman.nhm.ku.edu/mailman/listinfo/taxacom

The Taxacom archive going back to 1992 may be searched with either of these methods:

(1) by visiting http://taxacom.markmail.org <http://taxacom.markmail.org/> 

(2) a Google search specified as:  site:mailman.nhm.ku.edu/pipermail/taxacom  your search terms here