HYDERABAD : Was a part of Telangana under sea once upon a time due to climate change?
Palaeobotanists have come across fossils of extinct marine algae while studying micro fossil samples from Telangana. These fossils are from Permian period, between 299 and 251 million years ago, before even dinosaurs existed. Palaeobotanists study fossils of plant, pollen, plankton and other spores.
Fossils of three extinct marine algae
Tetraporinia, Balmeela and Leiosphaeridia, have been discovered from different sites in Bhadradri-Kothagudem district.These fossils were found by studies conducted earlier at Manuguru by scientists K Pauline Sabina and Neerja Jha from Birbal Sahni Institute of Palaeobotany (BSIP) and recently in a study on coal samples from Yellandu coalfield by DS Seetharam Naik of Osmania University.
Naik says that existence of marine algal fossils show that there was marine incursion.
Marine incursion is sea water coming into land due to severe climate change, causing melting of glaciers triggering rise of sea levels.
Fossils of pollen and other plant material from coal samples reveal that millions of years ago Telangana was cool/temperate, humid and landscape was dominated by conifers.
In the coal samples from Yellandu fossils of pollen belonging to 20-23 species of gymnosperms that were found and from Manuguru the number was 20.
Gymnosperms are a group of seed producing plants which do not bear fruits, like the conifers.
He says, “Looking at the pollen fossils it can be deduced that during Permian period the landscape was dominated by conifers and climate was humid and temperature ranged anywhere between cool to temperate.”
How did pollens end up in coal?
Shreya Mishra, a scientist at BSIP says, “During Permian, thick vegetation died and got buried along lakes and river channels. This buried vegetation turned into coal due to very high temperature and pressure during the course of millions of years.”
Seetharam says there are evidences that wildfires were also common during Permian period which also helped in formation of coal. However, in both cases what saved pollen from getting burnt is the chemical Sporopollenin present in its outer walls, which saves it from getting charred. The unburnt pollen wall turns into fossil over millions of years.
Significance of these findings
Mishra says, “Studying phenomena that significantly altered life on Earth can build an understanding about the future. Earth’s most devastating extinction event occurred during the end of Permian. Extinctions are followed be evolution of new plants and animals and again extinction.”