If there are 1 k to 1 M Demodex mites in each human, and each mite has 1 k neurons (spiders have 100 k according to this), mites in each human total 1 M to 1 G neurons. According to this, fruit flies and chickens have 100 k and 221 M neurons, so the mites in each human have as many neurons as:
For a lower bound, 10 fruit flies (1 M = 10 * 100 k).
For an upper bound, 5 chickens (1 G = 5 * 221 M).
Moreover, the number of neurons severely underestimates the moral weight of arthropods. According to Rethink Priorities’ recent estimates, the median moral weight of black soldier flies is 0.013, which is 10 k times as large as the weight of 10^-6 (= 100 k / 100 G) suggested by direct comparison with the 100 G neurons of each human.
For these reasons, I would not be surprised if the scale of the welfare of Demodex mites exceeds that of factory-farmed animals. One could say this latter problem is more tractable, but mites being way more neglected makes me think they are super underrated.
Interesting, thanks for writing this!
If there are 1 k to 1 M Demodex mites in each human, and each mite has 1 k neurons (spiders have 100 k according to this), mites in each human total 1 M to 1 G neurons. According to this, fruit flies and chickens have 100 k and 221 M neurons, so the mites in each human have as many neurons as:
For a lower bound, 10 fruit flies (1 M = 10 * 100 k).
For an upper bound, 5 chickens (1 G = 5 * 221 M).
Moreover, the number of neurons severely underestimates the moral weight of arthropods. According to Rethink Priorities’ recent estimates, the median moral weight of black soldier flies is 0.013, which is 10 k times as large as the weight of 10^-6 (= 100 k / 100 G) suggested by direct comparison with the 100 G neurons of each human.
For these reasons, I would not be surprised if the scale of the welfare of Demodex mites exceeds that of factory-farmed animals. One could say this latter problem is more tractable, but mites being way more neglected makes me think they are super underrated.