[InclinedPlane]

Indeed, that's a pretty good accessible overview. Most people can't comprehend the amount of energy involved in such an impact, but it would have spelled doom for the vast majority of above ground animals. Literally roasting them alive and killing so many of them that even if a few got lucky and survived they wouldn't have been a viable species. As to the aftermath and the impact on all the other organisms, that's likely a much more complicated story which we still haven't worked the details out of.