A sighting of a mother dolphin carrying her dead and decomposing calf around Whangarei Harbour has scientists saying the marine mammals are more like people than thought.
Dr Ingrid Visser from Orca Research was following the mother dolphin and told Close Up that while that sort of behaviour is not unusual for dolphins, it is not often witnessed by humans.
She says what happened in Whangarei Harbour should give people more of an understanding and respect for the animal.
"It's them trying to grieve as well look after what they don't understand is a dead animal," Visser said.
"We're not really sure why the behaviour has evolved, but we think it's got something to do with the group structure and the way they support each other and care for each other."
She says scientists have found that some species of dolphins and whales have similar neurons in the brain as humans, that have been shown to be associated with empathy and grieving.
"Dolphins have these same spindle neurons and actually they have more of them than we do," Visser said.
"As someone who's really strongly emotionally involved with these animals, I would say 'yes, they certainly do have a lot of qualities that we would regard as human'."
Visser said it was hard for her not to intervene and help the dolphin she knew as 'Potato'.
"It's certainly not healthy for her in terms of the biological side of things because the rotting carcass will have bacteria in it and she's got it around her face. At times she's got it right near her blowhole so she'll be breathing it in.
"But what can you do? If we took the carcass away from her it might even cause more problems for her."
Visser says that records from overseas show dolphins will carry the carcasses for up to six days.