3. Fossils of maples (based on the document No18 ) ............ Japanese
... Maples are also known as a plant with lots of fossils.
According to document 18, about 60 M.Y.B.P.(Million Years Before Present)
maples began to appear in this world,
and about 37-25 M.Y.B.P. there was a remarkable differenciation.
... In Japan, fossil maples from about 2 M.Y.B.P -10 thousand years B.P.were discovered
at Shiobara town in Tochigi Prefecture,
and of about 12 - 6 M.Y.B.P. at Yuzawa city in Akita Prefecture.... When I visited the Shiobara spa. before, I got some fossil maples
at Konoha-Fossil Garden for several hundred-1 thousand yen.
On the piece of guide as follows, the left one seems to be an "Acer micranthum",
the right one seems to be an "Acer mono".
... The hill in Konoha-Fossil Garden is about 20m tall,
and it is made of thousands of layers which are piled and generated by lake.
The thickness of the layers are from 3cm to 15cm.
Well, the evolution of maples is described in the next documents :
document No.4 : "Maples of the World"
document No.18 : "The Evolution of Aceraceae" by Tanai Toshimasa