Link goes to a Yale Public Affairs & Communications summary of the article just published in Science, titled "On impact and volcanism across the Cretaceous-Paleogene boundary" at <a href="https://science.sciencemag.org/content/367/6475/266" rel="nofollow">https://science.sciencemag.org/content/367/6475/266</a> .<p>Here's Science's even shorter summary (short enough to quote for HN), though with fewer details than Yale's:<p>> Around the time of the end-Cretaceous mass extinction that wiped out dinosaurs, there was both a bolide impact and a large amount of volcanism. Hull et al. ran several temperature simulations based on different volcanic outgassing scenarios and compared them with temperature records across the extinction event. The best model fits to the data required most outgassing to occur before the impact. When combined with other lines of evidence, these models support an impact-driven extinction. However, volcanic gases may have played a role in shaping the rise of different species after the extinction event.