[Taxacom] 53 million year rabbit foot

Ingo Michalak isoran at gmx.de
Mon Nov 21 14:55:15 CST 2011


:S
great... confusion worked... let me rephrase:

Dear Jason,

I rather think it is THE STEM age you can assign the fossil age to (as
a minimum), and NOT THE CROWN age. (Why should the "sample" of extant
spp. somehow have an influence to the placement of the fossil?)

Best


Ingo



schrieb Ingo Michalak:
> Dear Jason,
>
> I rather think it is the crown age you can assign the fossil age to (as
> a minimum), and not the stem age. (Why should the "sample" of extant
> spp. somehow have an influence to the placement of the fossil?)
>
> Best
>
>
> Ingo
>
> schrieb Jason Mate:
>>
>>
>>
>> ´´I agree with you that a well-dated fossil puts a minimum age for the clade. But one has to be careful about assuming any phyletic relationships, for even the oldest members of a clade can exhibit unique specializations, thus likely representing any of a multitude of extinct lineages. Insular forms of Lagomorpha have existed at different times, and islands are a common feature since the break-up of Pangaea.´´
>> We agree that we are in agreement but I just want so say that I make no assumptions regarding the fossil. As you have said yourself assigning a fossil (in this case a Lagomorph) to a particular group within the crown clade requires information which may or may not be available. That is why the most inclusive placement is the standard practice. If the fossil represents a Lagormoph sensu amplo then we can only speak for Lagomorpha as a whole and the fossil is a date for the crown node.
>> BestJason
>>
>>
>>    		 	   		
>> _______________________________________________
>>
>> 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
>>
>> (2) a Google search specified as:  site:mailman.nhm.ku.edu/pipermail/taxacom  your search terms here
>>
> _______________________________________________
>
> 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
>
> (2) a Google search specified as:  site:mailman.nhm.ku.edu/pipermail/taxacom  your search terms here
>



More information about the Taxacom mailing list