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• how do we know scallops/oysters cannot feel pain? (2026/03/18 06:34)

  In my marine conservation biology class, we recently learned about fish possessing nociceptors which suggest their ability to feel pain. We know this about fish, but I was wondering if this is the same for bivalves? According to my (admittedly brief) Google searches, both scallops and oysters have nociceptors, which makes me think they are also capable of feeling pain. Both also lack central nervous systems however, which suggests the opposite. So are the nociceptors just there to trigger muscles to respond to a stimuli? How can it be proven there is a lack of any pain? Is it just due to a lack of brain activity?