Buy Plant Fossil
FERNS – there are more than 11,000 species of fern today, making them the largest
group of plants after the flowering plants, or angiosperms.
Like many other types of simpler plants they reproduce by spores.
Ferns first appeared in the Devonian, thrived throught the Carboniferous, became
less common during the Late Permian and the Middle Cretaceous, but underwent a
resurgence during the Tertiary.
The seed ferns or pteridosperms were once group with the true ferns. However,
discoveries during the last century showed that these plants reproduced by seeds,
which form when female and male structures come together at fertilization, as in
the conifers and flowering plants.
This was an advance on more primitive spore-bearing methods used by horsetails,
ferns and other simpler plants.
The leaves or fronds, of seed ferns are commonly found in “Coal Age” Carboniferous
deposits, mainly across the Northern Hemisphere. As explained on previously,
the different parts of what is now known to be a single plant have often received different
names.
Seed ferns combined features of the ferns with characteristics of the more advanced
trees known as cycads.
Further Reading