"Within a temperate forest beneath a Glossopteris tree, a gorgonopsid, Lycaenops, guards over its prey, a dicynodont, Endothiodon. The approximate length of Lycaenops is 1.2 m (4 ft), and Endothiodon 1.1 m (3 1/2 ft)."

Glossopteris leaf

This is a fossil leaf of an ancient fern-type genus called Glossopteris. It was an important piece in the puzzle of reconstructing past continents on our planet. Fossils such as this one are found in Australia, Antarctica, Africa, South America, India and Madagascar. This fossil along with the other pieces of evidence allowed geologists to reconstruct the supercontinent of Gondwana, as Glossopteris was not found anywhere else which indicates that these continents must have once been joined.

The Tongue, Glossopteris (1828)

Kingdom : Plantae Division : Pteridospermatophyta Order : Glossopteridales Family : Glossopteridaceae Genus : Glossopterus Species : G. angustifolia, G. brasiliensis, G. browniana, G. communis, G. indica, G. occidentalis

Permian

7 m high (size)

Sourthern hemisphere (map)

They are interpreted to have grown in very wet soil conditions, similar to the modern Bald Cypress. The leaves ranged from about 2 cm to over 30 cm in length.

The profile of glossopterid trees is largely speculative as complete trees have not been preserved. However, based on analogies with modern high-latitude plants Glossopteris trees probably tapered upwards like a Christmas tree and were relatively widely spaced to take advantage of the low-angle sunlight at high latitudes. Instead of needles, they had large, broad lance- or tongue-shaped leaves that fell to the ground at the end of summer. The fossil leaves are commonly found as dense accumulations representing autumnal leaf banks. The broad fossilized growth rings in many Glossopteris woods reveal that the plants experienced strong growth spurts each spring-summer but underwent abrupt cessation of growth before each following winter.

Glossopteris leaves are morphologically simple so there are few characters that can be used to differentiate species. Consequently, many past researchers have considered the PermianGlossopteris flora to be rather homogeneous with the same species distributed throughout the Southern Hemisphere. However, more recent studies of the more morphologically diverse fertile organs have shown that taxa had more restricted regional distributions and several intra-gondwanan floristic provinces are recognizable. Seeds, much too large to be wind-borne, could not have blown across thousands of miles of open sea, nor is it likely they have floated across vast oceans. Observations such as these led the Austrian geologist Eduard Suess to deduce that there had once been a land bridge between these areas. He named this large land mass Gondwanaland (named after the district in India where the plant Glossopteris was found). These same observations would also lend support to Alfred Wegener's Continental drift theory.