ochlospecies

[david baum]

>Well, let's take the word apart first.  "OCHL-O", from the Greek, means "a
>crowd, mob".  Thus, the term may have something to do with species evolution
>in crowded circumstances, vs the usual at the perimeter and in isolation.
>Robin Leech


The term "ochlospecies" does indeed come from this root but it has a quite
different meaning.  As I understand it (remembering back to Frank White's
lectures when I was an undergraduate), the term refers to widespread
"species" that show extensive, geographically-structured, morphological
variation.  A crude caricature might be: an ochlospecies is a lumpers
equivalent to a splitters "species complex."  Does this fit with other
people's understanding?

Going back to the original question, molecular data have great power to
detect whether groups of organisms have a unique genealogical history (have
been reproductively isolated for a long time).  My sense is that FW  would
have predicted that a local population sampled from an "ochlospecies" would
would be comprised of genetically similar individuals - but would not have
a unique genetic history relative to the forms found elsewhere in the
range.  Thus, they would show greater clustering in genetic space, but
would not be genealogically exclusive.

Is taxacom always so busy?

David








David Baum
Dept. Organismic and Evolutionary Biology
Harvard University Herbaria
22 Divinity Avenue
Cambridge MA 02138

Tel: (617)496-6744, -8766
Fax: (617)495-9484
dbaum at oeb.harvard.edu
http://www.herbaria.harvard.edu/~dbaum