The "WT's pessimist way of viewing things" reflects on you Renaia....you forget, or you refuse to accept that species have been vanished through out the millions of years of existence of plannet Earth.
The greatest extinction took place 45 million years ago when a commet struck the Earth and vanished almost ALL of the reptilian inhabitants at that time. The Era of the dinausaurus was ended, and new spieces emerged through that destruction making the way easier for the Homo Sapiens species to evolved.
The last extinction of species took place 10,500 when the last ice age ended killing mammals, like Moumouths and many more that do not exist today and we are seeing them at the Museums of Natural History...
So this plannet due to climate changes or other sources from outer space, killed and vanished entire species and life on Earth, more than we humans in our breif history of 100,000 years ever killed...