[Taxacom] Taxacom Digest, Vol 185, Issue 14

[Michael Heads]

Good questions.

1. The original distribution of a clade is established by evolution -
nearly always by in situ allopatric differentiation (vicariance) (not
chance = jump = long distance dispersal). The spatial pattern of
differentiation is repeated in a large number of taxa in the region and so
has a general (tectonic or climatic) cause. This original area of a clade
may be very large, e.g. if a worldwide form differentiates into northern
and southern hemisphere forms. The original distribution may be modified by
subsequent range expansion as part of a community-wide 'geodispersal' (not
by chance dispersal, a mode of speciation) caused by geological/climatic
change, or by range contraction.

2. As far as I know, areas of endemism for ants are always repeated in
other groups, consistent with the processes in 1. One example is  the group
of Leptomyrmex species in Australia with a phylogenetic/biogeographic node
at the McPherson-Macleay Overlap (see my Australasia book, Fig. 4.16).



On Wed, Sep 22, 2021 at 5:54 PM Brendon E. Boudinot <boudinotb at gmail.com>
wrote:

> Dear John and Michael,
>
> Would you explain in ≤ 300 words for each point (vis à vis an abstract):
> 1. How extant (and extinct) species came to be distributed as they are.
> 2. How ant biogeography can be explained by point 1 above.
>
> This would be the best way of proceeding in our conversation.
>
> All the best,
> Brendon
>


-- 
Dunedin, New Zealand.

My books:

*Biogeography and evolution in New Zealand. *Taylor and Francis/CRC, Boca
Raton FL. 2017.
https://www.routledge.com/Biogeography-and-Evolution-in-New-Zealand/Heads/p/book/9781498751872


*Biogeography of Australasia:  A molecular analysis*. Cambridge University
Press, Cambridge. 2014. www.cambridge.org/9781107041028


*Molecular panbiogeography of the tropics. *University of California Press,
Berkeley. 2012. www.ucpress.edu/book.php?isbn=9780520271968


*Panbiogeography: Tracking the history of life*. Oxford University Press,
New York. 1999. (With R. Craw and J. Grehan).
http://books.google.co.nz/books?id=Bm0_QQ3Z6GUC
<http://books.google.co.nz/books?id=Bm0_QQ3Z6GUC&dq=panbiogeography&source=gbs_navlinks_s>