TITLE:
A Left-Handed, Stem-Twining Plant from the Miocene Shanwang Formation of Eastern China
AUTHORS:
Qi Wang, Si Shen, Zhenyu Li
KEYWORDS:
Climbing Growth Habit; Handedness; Liana; Miocene; Shanwang Formation; Stem-Twining Plants; Vine
JOURNAL NAME:
American Journal of Plant Sciences,
Vol.4 No.5A,
May
30,
2013
ABSTRACT: Twining stems
of plants are very common in extant tropical and subtropical forests,
and the climbing growth habit of plants may be an evolutionary innovation and
ecological adaptation to either closed, shady or open, edge environments.
However, the origin of handedness in climbing plants remains unclear. Here we report a Miocene (ca.
16 million years ago) macrofossil from the Shanwang Formation of Shandong
Province, Eastern China, unequivocally
exhibiting the first direct fossil evidence for a left-handed, stem-twining
growth habit in plants. This fossil plant bears a thicker,
slightly curved supporting stem (2 - 3.5 mm wide), which
is loosely, spirally twined by a thinner stem (1.5 - 2
mm wide), possibly representing part of distal
branches from a liana or vine.