Friday Headlines, June 28, 2013
THE LATEST IN THE GEOSCIENCES
After a short hiatus due to illness, I’m back and busting with cool headlines in the geosciences!
Filed under “Cool Beans”
This volcano has been going off for a while. On June 17th, someone got video of the volcano blowing its top. See the shock wave, falling debris, and the ash settling near the crater.
I admit, I don’t know a lot about this, but it keeps popping up on my Twitterfeed, and I want to know more. And you should too.
It seems that there’s lots of frozen carbon dioxide (AKA dry ice) on Mars. During the winter, its frozen in various places, including craters. In the summer, it sublimates (goes directly from solid ice to gas) due to the heat. (Don’t act surprised. This happens on Earth too. Ever seen a puddle of liquid carbon dioxide under a melting block of dry ice?)
It seems that when the seasons change, the dry ice melts (makes sense). When this happens, chunks break off and slide toward the center of the crater, completely evaporating in the process. This process leaves curious furrows or gullys in the crater walls.
The authors of the original study (paywalled, sorry) conducted experiments using blocks of dry ice on sand dunes in Utah, and were able to replicate some, but not all, of the features observed on Mars.
Pretty cool, if you ask me.
Your weekly paleontology headline:
Back in the Triassic Period, around 250 million years ago, mammals didn’t yet exist. There weren’t birds, and dinosaurs were still a few million years off. There were amphibians, though they didn’t look much like the modern salamanders and frogs we’re used to. And there were a group of animals called cynodonts, which are early ancestors of mammals. We were getting there.
One of these cynodonts (which are also sometimes called ‘mammal-like reptiles,’ though more properly would be called ‘non-mammalian synapsids’) was a little carnivore called Thrinaxodon (which I can never spell). Thrinaxodon enjoyed dining upon amphibians, most likely, and probably anything it could get it’s little teeth around.
When a complete skeleton of Thrinaxodon was found in a fossil burrow intertwined with a skeleton of an amphibian called Broomistega, it was natural to think that Thrinaxodon had brought the amphibian down for a snack. Using synchrotron imaging methods, scientists showed that it was in fact unlikely that the Thrinaxodon was making a meal of Broomistega.
No, it wasn’t interspecies love. The researchers present aestivation (essentially ‘hibernation’ during the hottest and dryest times of the year) of Thrinaxodon as the most plausible explanation. The Broomistega was an injured animal possibly crawled into the burrow for protection. The Thrinaxodon would have tolerated it because it was asleep.