An amber fossil discovered in southwest China's Tibet Autonomous Region suggests that rainforest was present in central Tibet more than 40 million years ago.

The research, jointly conducted by an international team of scientists from China, Britain and India, was recently published in Palaeoworld.

Wang Bo, one of the researchers from Nanjing Institute of Geology and Palaeontology, said that the amber fossil was discovered in the Lunpola basin in Tibet and derived from dipterocarp trees, which are today only found in Asian rainforest.

The scientists concluded that Tibet had a different geographical environment over 40 million years ago.

Based on previous research and biostratigraphy studies, they believe a tropical or subtropical rainforest with an altitude of less than 1,300 meters was once present in central Tibet.

However, an obvious uplift on the Qinghai-Tibet Plateau occurred around 25 million years ago. Plants such as pine and cypress, which can adapt to dry and cold weather, have started gradually growing there.