Researchers from Monash University in Australia reported the discovery of large trees, early flowering plants, seed cones and rare insects preserved in a rock formation in the Chatham Islands.
The fossils are the first evidence of life close to the South Pole during the Cretaceous period, 145 million to 65 million years ago, a time researchers say was a period of extreme greenhouse conditions on Earth.
"One hundred million years ago, the Earth was in the grip of a greenhouse effect -- a planet of extreme heat with minimal ice (except in the high altitudes) and sea levels of up to 200 meters (650 feet) higher than today," Monash paleontologists Professor Stillwell said.
In the Cretaceous period many southern continents including New Zealand, Australia, Antarctica and South America were still mostly joined together as part of the ancient southern landmass of Gondwana.
"Rainforests inhabited by dinosaurs existed in sub-polar latitudes and polar ecosystems were adapted to long months of winter darkness and summer daylight," Stillwell said.
The discovery was made in one of the most remote fossil locations in the Southern Hemisphere, more than 500 miles east of New Zealand.
"Never before have we had evidence about what life existed near the South Pole 90 to 100 million years, or the conditions that life on land experienced," Stillwell said.