http://www.newsweek.com/chicxulub-asteroid-how-much-climate-change-did-dinosaur-killing-asteroid-cause-943414

If you want to learn about the massive asteroid impact that triggered the extinction of dinosaurs, you might reach for dinosaur fossils. Or, it turns out, you could turn to a rather more humble form of scientific evidence: fish bones, teeth and scales each as small as a grain of sand.

That’s the approach taken by a new paper published in the journal Science. In it, a team of scientists use the chemical fingerprint in what’s euphemistically called “fish debris” to measure dramatic temperature changes caused by the massive asteroid impact about 65 million years ago. They say that the results could teach us what to expect from our own forays into the large-scale release of climate-altering gases.