Rethink Priorities’ (RP’s) median welfare range estimates, given in this post from Bob Fischer, for:
Black soldier flies, 0.013.
Silkworms, 0.002.
It’s worth noting that most arthropods by population are significantly smaller, have significantly smaller brains and would probably have less sophisticated behaviour (at least compared to adult black soldier flies; I’m not familiar with silkworm and other larval behaviour), so would probably score lower on both probability of sentience and welfare range. So, if you’re including all arthropods and using these figures for all arthropods, you should probably think of these numbers (or at least the BSF ones) as providing an overestimate of the arthropod welfare effects.
Thanks for pointing that out. I agree it is something worth having in mind.
However, the moral weight could still be much lower than those of black soldier flies and silkworms, and terrestrial arthropods still dominate. Assuming the moral weight is directly proportional to the number of neurons, in which case it is 0.0361 % (= 4.70 μ / 0.013) the one of black soldier flies, and 0.235 % (= 4.70 μ / 0.002) the one of silkworms, the mean cost-effectiveness would increase/decrease 353 % (assuming terrestrial arthropods have negative/positive lives).
It is true I may have overestimated the rate of deforestation, but I also expect the moral weight obtained by direct proportionality to the number of neurons to be an underestimate, so I think the analysis can go either way.
I think it would be really nice if Open Philanthropy, Rethink Priorities, Wild Animal Initiative, Faunalytics or other looked into considerations such this.
It’s worth noting that most arthropods by population are significantly smaller, have significantly smaller brains and would probably have less sophisticated behaviour (at least compared to adult black soldier flies; I’m not familiar with silkworm and other larval behaviour), so would probably score lower on both probability of sentience and welfare range. So, if you’re including all arthropods and using these figures for all arthropods, you should probably think of these numbers (or at least the BSF ones) as providing an overestimate of the arthropod welfare effects.
Hi Michael,
Thanks for pointing that out. I agree it is something worth having in mind.
However, the moral weight could still be much lower than those of black soldier flies and silkworms, and terrestrial arthropods still dominate. Assuming the moral weight is directly proportional to the number of neurons, in which case it is 0.0361 % (= 4.70 μ / 0.013) the one of black soldier flies, and 0.235 % (= 4.70 μ / 0.002) the one of silkworms, the mean cost-effectiveness would increase/decrease 353 % (assuming terrestrial arthropods have negative/positive lives).
It is true I may have overestimated the rate of deforestation, but I also expect the moral weight obtained by direct proportionality to the number of neurons to be an underestimate, so I think the analysis can go either way.
I think it would be really nice if Open Philanthropy, Rethink Priorities, Wild Animal Initiative, Faunalytics or other looked into considerations such this.