Just a note concerning the landsnails: large parts of India, especially the
southern, drier parts are inhabitat by several species which do occur also
in Iran, Iraq, several other Arabian countries and Africa! To give two
examples: Zootecus insularis and Pupoides coenopictus. The latter is even a
native species of Israel and Jordan too, where it occurs in the drier part
of the Syrian Rift valley. They have probably to be considered as very old
elements in the terrestrial fauna of these areas.
Henk K. Mienis


----- Original Message -----
From: "Andy Rindsberg" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Thursday, January 22, 2004 8:57 PM
Subject: Re: 7


> > Continents are geological structures, and no, size does NOT count.
>
> Thanks, Andrew G, but of course a snail or flower wouldn't know a tectonic
> plate if it hit them. Biologically, a continent can be considered, at
least
> for purposes of argument, as a large, contiguous body of land. I suppose
one
> can dispute whether Africa is part of Eurasia, and whether the Americas
> constitute a single continent. Biologically, the isthmuses (isthmi?) of
> Sinai and Panama do not allow all sorts of plants and animals to move from
> one body of land to the other, so one can well argue that North and South
> America are separate continents. It's hard to argue that Europe is a
> separate continent from Asia however.
>
> Biological provinces, now, that's another issue! India is separated from
the
> rest of the world by seas, mountains and deserts on most sides, being open
> to similar environments only on the eastern side. One would expect land
> snails and freshwater mollusks to diffuse relatively easily from the wet
> parts of India to Burma and southeast Asia generally, but not to Iran or
> China.
>
> Andrew K. Rindsberg
> Geological Survey of Alabama
>
>