I think I explained everything but the Harvester, as I explicitly stated that the Ripper was supplanted by the Shredder, and that the Arisian Zebedi-derivatives wiped out the Sejessian Hobo-derivatives. For the record, the harvester was outcompeted by its diverse descendants, in a manner similar to the Ripper.
That said, extinctions will happen when a species is supplanted in its niche by another species, or when its niche disappears entirely. I'd think it should usually be fairly straightforward when something goes extinct, but I'll try to include mentions of extinctions, usually in the sections of the organisms responsible. If I don't do that, then I can definitely answer questions about specific extinctions after the update.
That said, extinctions will happen when a species is supplanted in its niche by another species, or when its niche disappears entirely. I'd think it should usually be fairly straightforward when something goes extinct, but I'll try to include mentions of extinctions, usually in the sections of the organisms responsible. If I don't do that, then I can definitely answer questions about specific extinctions after the update.
