Thanks, Larks. I think the time for which Earth will remain habitable to non-human animals without the intervention of humans or our descendents is relevant for longtermists.
I believe the absolute value of the welfare of non-human animals is much larger than that of humans. I estimate soil nematodes have 169 times as many neurons as humans, and I guess the absolute value of welfare per neuron-year increases as the number of neurons decreases.
@Larks, in addition, the Earth remaining habitable for a shorter window of time implies a lower chance of a species as valuable for the future as humans evolving after human extinction. If the time from human extinction to such a species evolving follows an exponential distribution with mean of 66 M years, the time since the last mass extinction, the chance of such species not evolving over 1 billion years is 2.63*10^-7 (= e^(-1*10^9/​(66*10^6))), but it is 2.26 % (= e^(-250*10^6/​(66*10^6))) over 250 M years. So the chance of such a species not evolving is 85.9 k (= 0.0226/​(2.63*10^-7)) times as high for 250 M years of habitability as for 1 billion years.
Thanks, Larks. I think the time for which Earth will remain habitable to non-human animals without the intervention of humans or our descendents is relevant for longtermists.
I believe the absolute value of the welfare of non-human animals is much larger than that of humans. I estimate soil nematodes have 169 times as many neurons as humans, and I guess the absolute value of welfare per neuron-year increases as the number of neurons decreases.
@Larks, in addition, the Earth remaining habitable for a shorter window of time implies a lower chance of a species as valuable for the future as humans evolving after human extinction. If the time from human extinction to such a species evolving follows an exponential distribution with mean of 66 M years, the time since the last mass extinction, the chance of such species not evolving over 1 billion years is 2.63*10^-7 (= e^(-1*10^9/​(66*10^6))), but it is 2.26 % (= e^(-250*10^6/​(66*10^6))) over 250 M years. So the chance of such a species not evolving is 85.9 k (= 0.0226/​(2.63*10^-7)) times as high for 250 M years of habitability as for 1 billion years.