9-million-year-old fossils show Bilaspur climate similar now

Vijay Mohan

Chandigarh, December 16

The recent discovery of nine million-year-old fossils of lizards and snakes in Bilaspur area of Himachal Pradesh has indicated that a seasonally wet sub-humid to semi-arid climate, with mean annual temperatures of around 15°C to 18.6°C prevailed in the area during that period. This is similar to climatic conditions in the area today.

Lizards and snakes are cold-blooded squamates whose distribution, richness and diversity are highly dependent on temperature and climatic conditions. For this reason, squamates are widely regarded as excellent indicators of past climates, particularly ambient temperatures.

This was for the first time that researchers documented the species, Varanus, a class of monitor lizards (varanids) and python, a large snake (natricid), from this region. The fossils are from Haritalyangar, a late Miocene hominid locality of India, dating back 9.1 million years, according to a statement issued by the Union Ministry of Science and Technology today.

The project was undertaken by experts from the Wadia Institute of Himalayan Geology, Dehradun, Panjab University, Chandigarh, Indian Institute of Technology, Ropar, and Comenius University in Bratislava, Slovakia.

“The occurrence of Varanus in Haritalyangar is important in regard to its past biodiversity because varanids have a limited fossil record in Asia. Also, the fossil Python from South Asia remains poor except for the earliest record from Gujarat and Pakistan. Co-existence of Varanus and Python, two iconic squamates, revealed a wider distribution of the clade in this southern Asian territory,” the statement said.