Friday Headlines, November 29, 2013
THE LATEST IN THE GEOSCIENCES
A cave with its own weather
How do you preserve 68-million-year-old soft tissue?
The Er Wang Dong (literally means ‘Second Royal Cave’ in Chinese) system is part of the Wulong Karst system in the Chongqing Municipality of China.
Karst is a type of land feature that forms when limestone is dissolved by water in rain, producing dramatic landscapes of giant spires of rock.
The dissolving power of water also results in elaborate cave systems, such as Er Wang Dong. There are several openings into the cave at low levels, but only one opening high up. Humidity is trapped, by this configuration, resulting in dramatic clouds.
One large chamber, aptly called Cloud Ladder Hall, was recently photographed, the erie fogginess captured in a caver’s headlamp.
A couple of years ago, back in 2007 (Really. It’s only been a couple of years. Right?), Mary Schweitzer and colleagues were able to extract and study the chemistry of proteins from Tyrannosaurus rex. Since then Schweitzer and colleagues have reported on many examples of soft tissue from dinosaurs being found.
This is a big deal, because conventional logic is that no soft tissues – muscles, organs, skin, or anything like that – are expected to last beyond a million years or so, and here they were analyzing proteins that were 68 million years old.
Obviously, there has been lots of skepticism, and there still is plenty, and will continue to be skeptics for a long time. One of the questions scientists have asked is ‘how can soft tissues be preserved for so long?’
Schweitzer’s group has now published a mechanism that explains how this can happen. It turns out that iron likely plays an important role in this preservation. Iron can react with proteins to form structures that are less likely to decay. As long as the burial is rapid and the specimen is kept away from air and humidity, the soft tissues can be preserved for a very long time, much like how formaldehyde is used as a preservative.
This is pretty exciting news. But don’t worry. Jurassic Park is still nowhere near becoming a reality.