Fossil remains of giant snakes 13 metres long and weighing around a tonne have been discovered in an ancient rainforest in South America, indicating tropical conditions during an ancient period of greenhouse warming were much warmer than expected.
Excavated from the base of one of the world’s largest open-pit mines, in Cerejon, Colombia, the new snake species Titanoboa Cerrejonensis is 58 – 60 million years old and suggests the average yearly temperature where the snakes lived was 30 – 34 degrees C per year, 3 – 4 degrees hotter than tropical rainforests are anywhere in the world today.
The research is to be published in the journal Nature and is of interest to climate scientists trying to predict how global warming could impact life in tropical rain forests in the future.
The paper’s co-author, Dr Carlos Jaramillo of the Smithsonian Tropical Research Institute, was in New Zealand last month and spoke to the Science Media Centre about the snake’s discovery.
Listen to an SMC interview with Dr Jaramillo by starting the player below
[audio:https://www.sciencemediacentre.co.nz/wp-content/upload/2009/02/carlos-jaramillo.mp3]
“Snakes cannot regulate their internal temperature, they have to rely on the external temperature, so there’s a relationship between how long a snake is and the mean annual temperature where the snake lives.”
“For many years there were many doubts about what happened to the tropics during global warming…now with this new data…I think we understand much better the dynamics of global warming in the geological record, which we can apply to understand better what is going to happen with the global warming we have right now.”
Registered journalists can log into the audio section of the SMC resource library to hear the complete interview with him.
Dr Matthew Huber, Associate Professor at the Purdue Climate Change Research Centre and currently a visiting researcher at GNS Science in Wellington, has written a commentary on the paper in the February 5 issue of Nature. He said of the research:
“This is a new method for estimating past temperatures so more work will be necessary over the coming years to confirm the results, but if we take them at face value they imply several things:
“First: The tropics are not buffered from climate change by some magical thermostat as has been proposed repeatedly by some climate and paleoclimate scientists over the years. Instead they warm substantially when the rest of the world warms.
“Second: In this past period of warmth (which was not the warmest of the past 65 million years, but much hotter than current conditions) tropical ecosystems as represented by this one site were apparently resilient. This is somewhat good news within the global warming context since it implies that at least on long time scales the tropics life may not come to a catastrophic end at least as long as the warming is not too extreme.
“Third: The greenhouse gas concentrations that we think occurred in the Paleocene are within the range that projections of the future within the next 50 to 200 years indicate, consequently it is our choice, at this time, to decide as a global society whether or not we want to commit to sending the world towards a Paleocene-like climate state.”
Dr Chris Hollis, a micropaleontologist at GNS Science and convenor of the conference where Dr Jaramillo presented his research said:
“This is a really exciting discovery and certainly was one of the most interesting findings presented at the CBEP conference. Together with palms growing in the Arctic and our own evidence for 30 degrees C seas – it’s all pointing to a far warmer world during the greenhouse climate of the early Paleogene – around 60-40 million years ago.
“One of the more startling features of this discovery is the age of fossil snake record – 58-60 million years ago is 5-10 million years before the extremely warm temperatures recorded for the Arctic and NZ – and suggests that around 55-50 million years ago the tropics may have been much warmer – even too hot for these giant snakes.”
Further Information
To talk to these or any other New Zealand scientists, please contact the Science Media Centre on tel: 04 499 5476 or email: smc@sciencemediacentre.co.nz.
Notes to Editors
The Science Media Centre (SMC) is an independent source of expert comment and information for journalists covering science and technology in New Zealand. Our aim is to promote accurate, bias-free reporting on science and technology by helping the media work more closely with the scientific community. The SMC is an independent centre established by the Royal Society of New Zealand with funding from the Ministry of Research, Science and Technology. The views expressed in this Science Alert are those of the individuals and organisations indicated and do not reflect the views of the SMC or its employees. For further information about the centre, or to offer feedback, please email us at smc@sciencemediacentre.co.nz.