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February 13, 2012

Basic Rocket Science

Rocket science may not be as hard as you think. Check out this video to learn about how rocket propulsion works:

h/t to Henry Reich on Google+

February 8, 2012

A (Cricket) Song Long Forgotten

Along with most soft tissue, color, and a host of other features of prehistoric life, the sounds those long-gone creatures made are lost through the depth of time. While we make inferences about the sounds made by Parasaurolophus, Tyrannosaurus rex, the earliest birds, and the other animals living at the time, those projections are just just guesses, based on an approximation of acoustic and air flow properties. If those creatures had vocal chords, or any soft-tissue mechanism for creating sound, then we today have no way of recreating those noises.

A singing modern cricket
From what-when-how
However, there are some animals that don't use soft tissue and complex skull structure to create sound. Modern crickets, katydids, and other insects in the Orthoptera order create sound by running a row of "teeth" on one wing across the other, similar to a violinist running a bow across the strings. These fine details, however, very rarely preserve in the fossil record. It was not until a very detailed specimen, from North China, was discovered that Dr Fernando Montealegre-Zapata and Professor Daniel Robert, experts in biomechanics, were able to determine how ancient crickets made noise, and what they would have sounded like. This 165 million-year-old cricket had similar stridulating organs (the mechanism used to make sound) to modern species, something that's never been seen before in a fossil. The team built a reconstruction of that structure, and compared it to many modern species, to determine what it sounded like. In fact, the fossil was so detailed that they could fully recreate the song of this species, named Archaboilus musicus. You can listen to it here.

Unless the laws of physics suddenly allow us to build a time machine to the past, we will never know exactly how the Jurassic landscape sounded. The discovery of A. musicus, and hopefully more insects like it, along with understanding the sounds made by amphibians, mammals, dinosaurs, and reptiles, based on what information we can glean from the fossils and what we know of modern creatures, will help us to slowly piece together a more dynamic landscape of the past, engaging not just the eyes, but the ears as well.

Source: Science Daily- Fossil cricket reveals Jurassic love song
Wired - 165-Million-Year-Old Cricket Song Comes Back to Life

February 6, 2012

The Extreme Tardigrade

Most extremophiles are bacteria, living in places like the deep-sea hydrothermal vents, sulfuric hot pools, oxygenless layers in the ocean, and other environments that are deadly to every other form of life. But there are a few extremophile animals, such as the tardigrade.

Impressed yet? These invertebrates are some of my favorite living animals, and are a fascinating study in how evolution works. We still barely understand extremophiles of this sort, and there's a lot more research to be done. If you are interested in learning more, there are some resources below the break.