Clarke, Steve (2020) When some animals are more equal than others. Animal Sentience 29(33)
Irina Mikhalevich and Russell Powell, Minds without spines: Evolutionarily inclusive animal ethics
Mikhalevich & Powell (2020) argue that we should attribute moral standing not only to vertebrates but also to certain invertebrates. M&P also object on ethical grounds to policies of scientific funding agencies that encourage scientists to replace vertebrates by invertebrates in research. M&P do allow that some invertebrates with brains may have lower levels of moral status than some vertebrates, but this seems to conflict with their case against replacement policies.