I was aware of the event and our role in it.
Somewhere around 99 percent of all species that have ever lived are now extinct due to mass extinction events. In fact, the last extinction event (K-Pg) wiped out most of the species that were hanging around at the time. Nature then took the evolutionary reins and gave us some new species in its wake.
This event is unique in that one species is playing a huge role in it. This event is unique to us because we're currently part of the ecological system, but more importantly because we're a significant cause of it.
What are the implications? Do we have a moral obligation to protect other species, because of our special capacity to do so? Does this mass extinction have negative ecological effects? Would any negative consequences bite humanity in the ass later on? Are we, as a product of evolution just as are all other species, simply part of the natural cycle?
I mean all of these questions in the most neutral way possible. Making a good, sound moral judgment of our part hinges upon them, which itself is important because it would contribute to a course of action (if any).
But just as we're allowed to mourn the deaths of individuals within a species, including our own, we're allowed to mourn the death of a species as a whole; regardless of the answers to these questions.