Dolphins are pretty smart. Their brain-to-body ratio is in fact second only to humans, and the cerebral folds that allow a more dense collection of grey matter are probably more wrinkly than a humans. It shouldn’t come as a particular surprise that dolphins even pass things on culturally (something that’s been discussed here before) –
In one recent case, a dolphin rescued from the wild was taught to tail-walk while recuperating for three weeks in a dolphinarium in Australia…After she was released, scientists were astonished to see the trick spreading among wild dolphins who had learnt it from the former captive…There are many similar examples, such as the way dolphins living off Western Australia learnt to hold sponges over their snouts to protect themselves when searching for spiny fish on the ocean floor.
Behavior is not just culturally expressed, it is both novel and conscious:
A dolphin’s ability to invent novel behaviours was put to the test in a famous experiment by the renowned dolphin expert Karen Pryor. Two rough-toothed dolphins were rewarded whenever they came up with a new behaviour. It took just a few trials for both dolphins to realise what was required. A similar trial was set up with humans. The humans took about as long to realise what they were being trained to do as did the dolphins. For both the dolphins and the humans, there was a period of frustration (even anger, in the humans) before they “caught on”. Once they figured it out, the humans expressed great relief, whereas the dolphins raced around the tank excitedly, displaying more and more novel behaviours.