Monday, April 23, 2012

I'm Yours, Earth

I should have posted this yesterday, but, well you read "procrastinator" on my profile so it shouldn't be all that surprising that I'm a little late with it. Hope you had a wonderful Earth Day!


Friday, April 13, 2012

Wednesday, April 11, 2012

The Beat of the Scientific Drum

Over at PLoS Blogs' The Student Blog they sum up the story of this video so well that I'm just going to quote it for you:
"The Blast lab at Imperial College, London, is a percussionist’s dream. During experiments, which examine the effects of explosions on humans, metal plates are bashed upwards under pressure, weights clang against each other and wooden planks are used for forcible adjustments to the machinery. These sounds happen over and over as the scientists run dozens of tests, seeking enough data to draw meaning from the noise. Taken out of context, a single action in the lab means little, but when orchestrated correctly, a coherent story about biomechanics can be told.

We spent an afternoon recording members of the lab as they performed repeated blast tests. The work would seem familiar to any musician – tuning instruments, setting up recording devices and repeating the same actions to get the desired result.

This video was constructed from scratch, using real sounds and footage from the lab. Some adjustment of the raw sound was necessary, and string sounds had to be recreated using stringed instruments. As with any complex project, pulling together the disparate pieces was a real challenge!

While it may seem lighthearted, there’s a strong message behind the video. The finished product of a scientific investigation, like a song, is inevitably the result of days of practice, experimentation and collaboration. A scientist might have an idea of what they want their investigation to sound like, but the process of science will throw up challenges, test creativity and occasionally uncover entirely new melodies."

Nacho Chemistry


A Beautiful Feathered Tyrant

photo credit: Brian Choo
The tyrannosaurids belong to a group of carnivorous dinosaurs called theropods within the Saurischia ("reptile-hipped") dinosaurs. The Tyrannosauroidea was one of the longest-lived theropod subgroups, extending from the Middle Jurassic to the Upper Cretaceous. They are characterized by massive skulls with short but deep jaws containing large sharp teeth, elongate hindlimbs, small eyes, and highly reduced forelimbs. The Tyrannosauridae taxon includes such creatures as Albertosaurus, Gorgosaurus, Daspletosaurus, Tarbosaurus, and of course Tyrannosaurus rex. These were the dominant large carnivores during the Late Cretaceous in North America and Asia, with T. rex being the last and largest of the terrestrial carnivores. Their fossils are actually relatively common in North America, particularly their teeth. Smaller members of this dinosaur subgroup (adults with a body mass less than 1,000kg) have recently been reported from the Lower Cretaceous of China. These relatively small tyrannosaurs range from about 1.4m to about 10m in body length, and they vary in their morphology with some resembling highly specialized Tyrannosauridae and others resembling coelurosaurs (theropods more closely related to birds than carnosaurs, such as Velociraptor). This variation in earlier species suggests that there may have been some significant radiation in this group.

A new paper in the journal Nature reports the discovery of a new feathered tyrannosauroid from the Lower Cretaceous. Three nearly complete skeletons representing two distinct ontogenetic stages were found in the Yixian Formation of Liaoning Province of China. The new species has been named Yutyrannus huali. Examination of bone characteristics and phylogenetic analyses place this new dinosaur among basal (not derived) tyrannosauroids yet close to Tyrannosauridae. In particular, the pneumatic midline crest of the cranium has homologous structures to Late Cretaceous tyrannosauroids while also having features that occur consistently in basal tyrannosaurids. Other cranial features (such as a large, deep skull) and a posteriorly tapering main body are similar to derived species, and the shoulder girdle, forelimbs, and hindlimbs are similar to basal species.

Figure 3: A simplified cladogram showing the systematic position of Y. huali among the Tyrannosauroidea
Finding three specimens at two distinct ontogenetic (or developmental) stages also allowed the researchers to look for morphological changes with increasing maturity. They found that as Y. huali matured it's skull and premaxilla changed significantly. These changes could be due to individual genetic variation or sexual dimorphism. The overall growth pattern of Y. huali differed from that of derived tyrannosaurids, with Y. huali showing negative allometry (relationship of size to shape) rather than the positive allometry and near isometry seen in tyrannosaurids.

Interestingly, filamentous integumentary structures (a.k.a. feathers) were found in all three of the Y. huali specimens. At this point you may be thinking: Feathers? In a fossil? And you'd be correct. The preservation of feathers isn't found all that often in dinosaur species, either because they had no feathers or because the feathers did not preserve. In these new specimens, the feather preservation is patchy (not uncommon even in species known to have a lot of plummage) but undoubtedly there. The feathers ran parallel to each other down the spine at a 30° angle with the long axis of the tail. These dorsal feathers were at least 15cm long and densely packed. Additional feathers were found extending from the dorsal side of the neck and near the humerus. These neck feathers were longer, measuring more than 20cm. The distribution of these feathers suggests that Y. huali may have been extensively feathered in life. However, the patchy nature of the preservation of the feathers may also indicate that the distribution of the feathers on the body may have been restricted and function as display structures as they do in some other theropod groups.

In terms of evolution, feathers and hair are often developed as insulators. It has been observed that some large mammals have become almost hairless because they have a low surface-to-volume ratio that allows them to retain body heat even though they have no hair. It has been suggested that the very large Late Cretaceous tyrannosaurs lack extensive feathering for similar reasons. There is fossil evidence for patches of scaly skin and no evidence for the presence of feathers in these gigantic tyrannosaurs. However, Y. huali is an earlier specimen. The authors speculate that the discovery of Y. huali "indicates that at least one gigantic dinosaur had an extensive insulative coat of feathers, showing in turn that drastic reduction of the plumage was not an inevitable consequence of very large body size. If Late Cretaceous tyrannosaurids such as Tyrannosaurus rex were similar to Y. huali in this respect, both basal and derived tyrannosauroid dinosuars would differ from mammals in lacking a tendency to lose their integumentary covering as result of gigantism." Alternatively, if scales were the dominant characteristics of the Late Cretaceous tyrannosaurs (who lived in a warm climate) then the presence of feathers in Y. huali could have been an adaptation to a cold environment.

ResearchBlogging.org Xu, X., Wang, K., Zhang, K., Ma, Q., Xing, L., Sullivan, C., Hu, D., Cheng, S., & Wang, S. (2012). A gigantic feathered dinosaur from the Lower Cretaceous of China Nature, 484 (7392), 92-95 DOI: 10.1038/nature10906

Nature article "Researchers Unearth Largest Feathered Dinosaur"

There is also a Nature Podcast of this story that aired on April 5, 2012 and it includes an interview with the study's author

(first image from the Nature story linked above)

Tuesday, April 3, 2012

Tyson Tunes Up Titanic


Neil deGrasse Tyson is an American astrophysicist and the director of the Hayden Planetarium. He is also a public figure who promotes science communication and education. And now Dr. Tyson has made another leap for accurate science communication, at least in Hollywood movies. This week marks the 3D re-release of James Cameron's Titanic.  When the movie originally debuted in 1997, Tyson noted an astronomical inaccuracy. The scene features Rose (Kate Winslet) floating on a piece of driftwood and looking up at the sky. The sky in question has a star field that is incorrect for the night of April 15, 1912 at 4:20 AM. Tyson has brought the point up repeatedly as the two ran into each other over the years. While working on his movie for 3D post-conversion, Cameron's team asked Tyson to send over an accurate sky map for that date and time. I don't know about you, but I count that as a win for science.

James Cameron and Titanic aren't the only high-profile media that Tyson has taken to task for their scientific inaccuracy. If you watch Comedy Central’s The Daily Show with Jon Stewart, then you will remember that Tyson pointed out that the globe at the beginning of Jon's was spinning in the wrong direction. In addition, Tyson’s pointed out Cameron’s inaccuracy and others in his book Cosmic Quandaries, as well as in a panel discussion at St. Petersburg College. Watch the very entertaining discussion below (it is a very long video so skip to 23:50 for just the rant on Titanic):



(story and image via /Film)

Sunday, April 1, 2012

Ph.Diddy is on the Scene

Meet this super fly grad.

Love Your Insides

Giant microbes have been around for a while, and have quite a large following. Now, take a look at the new plush sensation: I Heart Guts. Yep, give the gift of guts. Your favorite organs in plushie form. Here are a few of the cute little organs:

This ovary plush is an ova achiever

I Got The Beat, the heart plush
This prostate plush is a seminal work
Don't hold your breath, hold this lungs plush


Find more guts to love over at http://iheartguts.com/

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