Megalodon Extinction May Have Been Driven by Hungry Great White Sharks

The largest shark that ever lived may have vanished in part because the comparatively smaller great white had a taste for the same prey.

#endangered-and-extinct-species, #fossils, #isotopes, #nature-communications-journal, #paleontology, #research, #sharks, #teeth-and-dentistry, #your-feed-animals, #your-feed-science, #zinc

Why Do Humans Feed So Many Animals?

Researchers want to learn more about the connections between humans and the feeding of birds, beasts and other fauna.

#animal-behavior, #archaeology-and-anthropology, #birds, #cats, #delhi-india, #dogs, #great-britain, #isotopes, #monkeys-and-apes, #pet-foods, #pets, #rome-italy, #your-feed-science, #zoos

New data is evidence of process that powers exploding stars

image of a multicolored blob.

Enlarge / A multi-wavelength image of the Cassiopeia A supernova remnant. (credit: Courtesy NASA/JPL-Caltech)

Supernovae happen. We’ve witnessed enough of them that we’re pretty sure of that. Why they happen has been another issue entirely. As we’ve worked on understanding the physics that drives these immense explosions, we’ve occasionally gone through awkward periods when the stars in our models stop exploding. Adding in more realistic physics has generally gotten the models booming again, and right now we’re in a period where the latest models appear to be happily self-destructing.

The challenge is trying to find evidence that the physics we’re using in our successful models accurately reflects what’s going on in a dying star—not an easy task with an event that instantly destroys much of the evidence.

Now, data from the Chandra X-ray Observatory provides a hint that a mechanism used in recent supernova models is probably right. The results are published in this week’s issue of Nature.

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#astrophysics, #isotopes, #physics, #science, #supernova

The Romans Called it ‘Alexandrian Glass.’ Where Was It Really From?

Trace quantities of isotopes hint at the true origin of a kind of glass that was highly prized in the Roman Empire.

#archaeology-and-anthropology, #chemistry, #egypt, #glass, #glassware, #isotopes, #mediterranean-sea, #research, #roman-civilization, #your-feed-science