“In that sense, at the species level, all extinctions that have occurred in Earth history are the same.” However, the scale and frequency of extinctions vary widely and are the subject of a heated, ongoing scientific debate.
Low-level, “Background” Extinctions are Ongoing
Scientists believe that "natural" extinctions go on all the time, but at very low or "background" rates. These background extinctions typically occur in a random or uncorrelated manner with life remaining stable unless major ecosystem-wide disruption occurs, in which case wide-scale extinctions may occur. These mass extinctions are at the opposite end of the spectrum from background extinctions.