Dolphins 'are stupid':
"Manger said observed behaviour supports his iconoclastic take on dolphins as dim-wits.
'You put an animal in a box, even a lab rat or gerbil, and the first thing it wants to do is climb out of it. If you don't put a lid on top of the bowl of a goldfish it will eventually jump out to enlarge the environment it is living in,' he said.
'But a dolphin will never do that. In the marine parks the dividers to keep the dolphins apart are only a foot or two above the water between the different pools,' he said.
Why not? Because, Manger says, the thought would simply not cross their unsophisticated minds.
They jump through hoops at marine parks only because they have been conditioned to for a food reward - which may suggest the brain of a single-minded predator rather than a reasoned thinker.
'Dolphins can actually chain up to 16 stimulus response events, but this is indicative of good trainers and not intelligent animals. Stimulus-response conditioning is thought to be a low level of intelligent behaviour,' Manger said.
Manger also points to the tuna industry, which under consumer pressure has gone to great lengths to prevent dolphins from being caught and killed by accident in nets.
'If they were really intelligent they would just jump over the net because it doesn't come out of the water,' he said."