The Greek island of Lesvos contains a unique Miocene petrified forest. Systematic study of the petrified trunks, leaves, fruits and seeds has led to the identification of the genera and species which made up the forests of Lesvos between 20 and 16 Ma. The fossilized flora consists of pteridophytes, conifers, and angiosperms. The conifers include ancestral forms of the sequoia, pine, cypress and other rare species for which there are no modern equivalents. A large number of fossilized trees belong to the ancestral form of the present day Sequoia sempervirens, which currently grows on the west coast of the United States. Protopinaceae have also been identified. These are ancestors of the modern day pine, cypress and the rare Cunninghamia miocenia. Angiosperms (flowering plants) include species of poplar, laurel, cinnamon, plane, oak, lime, beech, alder and maple have been found. Also, various types of palms have been identified. What is unique about this petrified forest is that many of the fossils have been found in situ; including a giant sequoia stump which is over 10 metres high and was when alive is estimated to have been over 92 metres in height. Fundamental questions remain.
1. What condition created the perfect environment to preserve the best fossilized forest found in the World.
2. Why is there a succession of different biomes between 20 to 16 Ma; starting with palms, followed by sequoia, then pines and then angiosperms.
3. How did these different environments exist and evolve in the Mediterranean during the Miocene.