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For approximately 15 years, our laboratory has been working on various aspects of Late Permian (~250 million years ago)
and Middle Triassic (238 myr) floras from Antarctica. The best of these floras is anatomically preserved, so that every cell within the plants is intact,
a preservation process called permineralization. Permineralized deposits are the rarest form of plant fossil preservation and can reveal a great
deal of information about anatomy, morphology, and reproductive biology, as well as plant-animal and plant-microbe interactions in the ecosystem.
In addition, the floras from Antarctica are particularly important since we know very little about the plants that lived during the Permian and Triassic,
due to generally poor preservation of floras elsewhere in the world. During these time periods a number of unusual seed plant groups evolved,
several of which have been implicated as possible ancestors of the flowering plants (angiosperms), the group that dominates the world today. The
availability of anatomically preserved material from these groups has furthered our knowledge of seed plant evolution in the late Paleozoic and Mesozoic
considerably.
This research has already produced significant results including:
- The oldest, anatomically preserved fossil cycad (Smoot et al., 1985) and associated pollen cone (Klavins et al., 2003)
- Evidence of polyembryony in Permian seeds (Smoot and Taylor, 1986)
- Two standing fossil forests which grew at very high paleolatitudes (80-85º S in the Permian; 70-75º in the Triassic)
(Taylor et al., 1992; Cúneo et al., 2003)
- Anatomically preserved reproductive organs of the Permian seed ferns, Glossopteridales (Taylor and Taylor, 1992) and associated
stems and leaves (Pigg et al., 1990, 1993)
- The discovery that Triassic Dicroidium-type leaves were borne on different stem types in East Gondwana and West Gondwana
(Meyer-Berthaud et al., 1993)
- A completely new group of Mesozoic seed ferns, the Petriellales, which show some characters similar to the flowering plants
(Triassic) (Taylor et al., 1994)
- Triassic specimens of Osmunda, the "interrupted fern," which appear almost identical to modern forms (Phipps et al., 1998)
- Data on paleoclimate in Antarctica based on fossil tree rings, indicating that the poles were warmer than has been suggested from
physical paleoclimate models (Taylor et al., 2000)
- The first evidence of the attachment of Dicroidium fronds, the most common leaf type in the Triassic of the southern hemisphere,
to stems that also bear seeds in cupules (Axsmith et al., 2000)
Thomas N. Taylor and
Edith L. Taylor
are also engaged in a revision of their 1993 textbook, The Biology and Evolution of Fossil Plants (Prentice-Hall, Inc., 982 pp., 1611 figs.),
which is currently out of print.
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