Re: Fossil Record 2 database

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Peter Sheehan writes:

>My guess is that your son will be more interested in how families of 
>horses or graptolites lived rather than how many species were in the 
>family.  If the study of life on earth was just a matter of figuring out 
>how many species were present now or in the past I would get out of the 
>business.

There it goes again -- my own rhetorical devices (in this case, hypothetical
sonny boy) getting me into trouble.  No question that how ancient organisms
got along and what adaptations they used to do it are rich lines of inquiry.
Queries about timing and extent of diversification are valid too.  What my
little trope may have failed to get across is my doubt that a bean-counting
style of systematics can take us much farther than it has already.

No paleontologist I know would ask the question "how many species make a
family?" with a straight face.  At some point in our education we learned
not to.  I can't recall the text; in my case it was probably just one of
those things I soaked up.  A family is a grouping of genera -- what other
definition is there?  What do the taxa Helminthoglyptidae, Hominidae, and
Rosaceae have in common that makes them all "families?"

Then Neil Clark writes:

>I would add that there is no need to have a constant interpretation as 
>to what a Family represents in terms of its relationship with other 
>Families.  Especially as we are not sure even whether species-level 
>taxonomy is equivalent in either living or fossil organisms.

This one confuses me.  In a classification, two families would represent two
mutually exclusive groups of genera.  But in a phylogenetic analysis, one
"family" of canonical systematics may turn out to be a subset of another
"family."  Is it all right for both "families" to carry equal weight in an
analysis like Benton's?

 Barry Roth                             barryr@ucmp1.berkeley.edu
 Research Associate, Museum of Paleontology
 University of California, Berkeley, CA 94117 USA   (415) 387-8538