There happen to be two main criteria that most ethicists agree on for determining whether a living creature has the capacity to suffer and so has genuine interests that it may or may not be our moral duty to consider. 17 One is how much of the neurological hardware required for pain-experience the animal comes equipped with—nociceptors, prostaglandins, neuronal opioid receptors, etc. The other criterion is whether the animal demonstrates behavior associated with pain.
