 
Together
with more primitive land plants, Baragwanathia most likely grew partly
submerged in shallow water along the shoreline or in moist, swampy areas as a
sprawling plant among green scums of algae.
The greening of Earth’s land surface was
underway!
Baragwanathia longiofolia was
a primitive club
moss (Lycopod) and, although much larger, it looked remarkably similar to
the living, yet primitive, water tassel fern, Huperzia squarrosa
(previously known as Lycopodium
squarrosum).
It was quite different from other early land
plants elsewhere in the world at the time, including Cooksonia
(named in honour of Dr Isabel Cookson), which were small, with short, leafless
stems.
Baragwanathia’s long, narrow
leaves were spirally arranged on a stout, woody stem, reaching up to a metre or
more in length. It reproduced by
releasing spores from special structures at the base of the leaves and also,
possibly by underground stems that developed roots.
Significantly for a plant adapting to life
on land, Baragwanathia had a system of tiny internal tubes known as a
vascular
system.
These
special tissues conduct water and nutrients throughout the plant. They also provide support for the plant
so that it can stay upright and make more effective use of sunlight for
photosynthesis. This process
enables green plants to produce simple carbohydrates from carbon dioxide and
hydrogen, using energy that chlorophyll pigments absorb from the
sun.
All land
plants today have a vascular system except for algae, lichens, mosses and
liverworts.
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