Friday Headlines, July 5, 2013
THE LATEST IN THE GEOSCIENCES
Featuring one of my most favorite animals… Thylacosmilus:
Thylacosmilus is, to the untrained eye, a saber-toothed tiger. It was a powerful carnivore with big saber-like upper canines and looked, superficially, very, very cat-like.
However, Thylacosmilus was a marsupial. Yup, one of those pouched mammals like the kangaroos. Definitely not a tiger.
Its upper canines were rooted between Thylacosmilus‘ eyes, rather than in front of the eyes like in Smilodon, to popular ‘saber-toothed tiger’ known popularly from the La Brea Tar Pits in California.
Thylacosmilus also, in contrast to Smilodon, had a long flange on its lower jaw against which sat the canines when its mouth was closed. In Smilodon, there is only a tiny extension of the lower jaw and the canine hung down unsupported beneath its chin.
Thylacosmilus is in the news because new studies have shown that its bite was weaker than that of modern domestic cats. Thycacosmilus compensated by having strong forearms for immobilizing prey animals. This combined with neck muscles stronger than those in Smilodon, allowed Thylacosmilus to deliver a very precise killing bite.
You can read more about this comparative study in the original article in PLOSone. It’s open access!
Here’s a fun geology one:
Volcanoes and earthquakes in a given area are often related to each other by plate tectonic processes. In places like Japan or along the Andes Mountain chain, where there is active subduction (the ocean floor being drawn under the continents), as well as huge volcanoes, earthquakes are common.
New studies by two separate research groups, one studying the massive 2011 earthquake in Japan and the other studying the 2010 earthquake in Chile, have shown that in the aftermath of the earthquakes, volcanoes nearby sank by as much as six inches.
The two studies differ in their conclusions as to what caused the sinking of the volcanoes, but it’s possible that these differences are due to the availability of data. And thus, this is how science works…