There are significant observational data to suggest that succourant behaviour is automatic in female dolphins, an essentially mindless response to certain triggering stimimuli, as in the example given earlier of a female bottlenose dolphin which carried a shark on its melon, taking it to the surface over and over again for days. It is not in fact necessary to postulate that the animal has to understand what it does in order for succourant behaviour towards peers to evolve, as long as it confers selective advantage. There are similar records of females taking stillborn calves to the surface over and over again for many hours, and of one doing this with a partly decomposed head. This, I suppose, brings us to the question of cetacean intelligence, which raises immediately the thorny and hoary problem of defining the concept. All animals can be shown to be intelligent to some degree, if one operates on an absolute scale.
Dolphins can perform quite complex tasks.
Bottenose dolphins, in particular, are superb mimics, can memorize long routines, and are amenable to training. They are not superb at solving problems, merely quite good by higher vertebrate standards and, as might well be expected, their auditory learning skills are considerable. They have been ranked at about the same level as the elephant in test scoring. Certainly some dolphin species exhibit individual behaviour of some complexity, and they sometimes spontaneously innovate. But so do many other mammals, a point which tends to be forgotten.