Leon Brooks, Wikimedia Commons // Public Domain
Leon Brooks, Wikimedia Commons // Public Domain

Mass Extinction That Killed the Dinosaurs Also Led to 'Explosive Radiations of Frogs'

Leon Brooks, Wikimedia Commons // Public Domain
Leon Brooks, Wikimedia Commons // Public Domain

You know what they say: Life finds a way. In this case, we're talking about frog life. Scientists say the mass extinction event that killed off so many dinosaurs may have paved the way for "explosive radiations of frogs," including the nearly 90 percent of species alive on Earth today. They published their report in the journal Proceedings of the National Academy of Sciences.

Previous research has suggested that the frog family party started about 100 million years ago. These studies based their conclusions on analysis of modern frogs' mitochondrial DNA, which can provide a sort of road map to an organism's evolutionary past. But sometimes that map is hard to read or even outdated.

To get a clearer picture, researchers from China and the U.S. decided to look at genes inside the nuclei, rather than the mitochondria, of frogs' cells. They compared nuclear (nucleus-based) genes among 301 different frog species, including one from each of the 55 major branches of the frog family tree.

Oddly enough, branches and trees may have been the key to the frogs' success. Analysis of the frogs' genetic histories suggests that the party really only started about 66 million years ago—just after so many of the dinosaurs were wiped out. It also reveals that nearly 90 percent of frog species today trace their genetic roots to just three frog lineages that survived the mass extinction.

But the researchers say it wasn't necessarily the dinosaurs' disappearance that made our planet a more frog-friendly place. The catastrophe that killed the thunder lizards also killed a lot of other things, including primitive prehistoric plants.

"We think the world was quite impoverished as a result of the [extinction event]," co-author David Wake of UC-Berkeley said in a statement, "and when the vegetation came back, angiosperms dominated. That's when trees evolved to their full flowering."

Seeing their opportunity, frogs began moving into the trees. And up there, they thrived.

Around the same time, Wake says, frog species that stayed on the ground learned their own neat trick: direct development, or skipping the tadpole stage, which requires access to water.

"This certainly draws renewed attention to the positive aspects of mass extinctions: They provide ecological opportunity for new things. Just wait for the next grand extinction and life will take off again. In which direction it will take off, you don't know."

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MARS Bioimaging
The World's First Full-Color 3D X-Rays Have Arrived
MARS Bioimaging
MARS Bioimaging

The days of drab black-and-white, 2D X-rays may finally be over. Now, if you want to see what your broken ankle looks like in all its full-color, 3D glory, you can do so thanks to new body-scanning technology. The machine, spotted by BGR, comes courtesy of New Zealand-based manufacturer MARS Bioimaging.

It’s called the MARS large bore spectral scanner, and it uses spectral molecular imaging (SMI) to produce images that are fully colorized and in 3D. While visually appealing, the technology isn’t just about aesthetics—it could help doctors identify issues more accurately and provide better care.

Its pixel detectors, called “Medipix” chips, allow the machine to identify colors and distinguish between materials that look the same on regular CT scans, like calcium, iodine, and gold, Buzzfeed reports. Bone, fat, and water are also differentiated by color, and it can detect details as small as a strand of hair.

“It gives you a lot more information, and that’s very useful for medical imaging. It enables you to do a lot of diagnosis you can’t do otherwise,” Phil Butler, the founder/CEO of MARS Bioimaging and a physicist at the University of Canterbury, says in a video. “When you [have] a black-and-white camera photographing a tree with its leaves, you can’t tell whether the leaves are healthy or not. But if you’ve got a color camera, you can see whether they’re healthy leaves or diseased.”

The images are even more impressive in motion. This rotating image of an ankle shows "lipid-like" materials (like cartilage and skin) in beige, and soft tissue and muscle in red.

The technology took roughly a decade to develop. However, MARS is still working on scaling up production, so it may be some time before the machine is available commercially.

[h/t BGR]

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ESA/Herschel/SPIRE; M. W. L. Smith et al 2017
Look Closely—Every Point of Light in This Image Is a Galaxy
ESA/Herschel/SPIRE; M. W. L. Smith et al 2017
ESA/Herschel/SPIRE; M. W. L. Smith et al 2017

Even if you stare closely at this seemingly grainy image, you might not be able to tell there’s anything to it besides visual noise. But it's not static—it's a sliver of the distant universe, and every little pinprick of light is a galaxy.

As Gizmodo reports, the image was produced by the European Space Agency’s Herschel Space Observatory, a space-based infrared telescope that was launched into orbit in 2009 and was decommissioned in 2013. Created by Herschel’s Spectral and Photometric Imaging Receiver (SPIRE) and Photodetector Array Camera and Spectrometer (PACS), it looks out from our galaxy toward the North Galactic Pole, a point that lies perpendicular to the Milky Way's spiral near the constellation Coma Berenices.

A close-up of a view of distant galaxies taken by the Herschel Space Observatory
ESA/Herschel/SPIRE; M. W. L. Smith et al 2017

Each point of light comes from the heat of dust grains between different stars in a galaxy. These areas of dust gave off this radiation billions of years before reaching Herschel. Around 1000 of those pins of light belong to galaxies in the Coma Cluster (named for Coma Berenices), one of the densest clusters of galaxies in the known universe.

The longer you look at it, the smaller you’ll feel.

[h/t Gizmodo]

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