J.E. Shields
Fri, 02 May 2008 13:23:22 PDT

Now that sounds quite intriguing.  It also sounds like it might get a bit 
technical, so perhaps we'll have to continue the discussion off list.  The 
Trillium are interesting, among other reasons, because they seem to 
interbreed promiscuously wherever their rangers intersect.  How real are 
any of the Trillium species?  Are they any older than 10,000-20,000 years, 
about when the last glaciation ended?

The previous interglacial period reached its warmest point at 126,000 years 
ago.  The last glacial age lasted from about 120,000 years ago up until 
about 12,000 years ago.  The peak of ice formation was probably about 
20,000 years ago.  The ice only reached down to about where I live -- 
central Indiana.  The unglaciated parts of North America may nevertheless 
have been cold, barren, and relatively dry.  Where were all the Trillium 
species during that ca. 100,000 years of glaciers?  I suspect that they 
were in today's coastal plains of Georgia, Florida, Alabama, and 
Mississippi; and the coastal plain species were out on the dry continental 
shelf areas now under up to 200 feet of sea water in the Gulf of 
Mexico.  They may have undergone new speciation processes in the course of 
surviving the long glacial age far from where they live today.  They may be 
undergoing new speciation at the present, as they encounter each other anew.

As I said, we should probably continue off-line.

Jim Shields
in currently unglaciated central Indiana, but where 20,000 years ago there 
would have been a mile of ice over my head.

At 08:49 PM 5/2/2008 +0100, you wrote:
>In his post, # 10, Jim Shields mentions a friend studying possible 
>relationships amongst Trillium, in particular the, or any, possible 
>"relationship within or between the yellow Trillium luteum and the 
>red-brown Trillium cuneatum along with plants of the latter within 
>populations of the former, posing the question, are they mutants or 
>hybrids". I would suggest neither.
>If Jim cares to put his friend in touch I think, initially we may have a 
>three way exchange before I stick my head above the parapet, as I may have 
>a possible suggestion based on a similar analogue I am researching now 
>within the genus Lilium. Early days at the moment but I am extremely 
>intrigued by this situation as it seems to confirm a hypothesis which I am 
>investigating, no more than an hypothesis quite yet and MIGHT? also have 
>an implication for the relative relationships between Liliaceae and 

Jim Shields             USDA Zone 5             Shields Gardens, Ltd.
P.O. Box 92              WWW:
Westfield, Indiana 46074, USA
Tel. ++1-317-867-3344     or      toll-free 1-866-449-3344 in USA

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