A five-tonne hippo shows she would certainly benefit from a trip to the dentist in this jaw-dropping moment captured by an amateur photographer. But her calf will certainly not be suggesting that she needs to have her pearly whites looked at, or joking that she is long in the tooth, having had a close up view of the powerful gnashers. The enormous hippopotamus is considered to be one of the world's most dangerous mammals and after catching sight of these terrifying teeth, it is easy to understand why.
But in this stunning series of photographs, the mother shows that hippos also have a gentle side, as she playfully splashes around while her offspring explores the world around them. Amateur British wildlife photographer Philip Cousins managed to take the shots of the hippos in conservation, at Valencia Zoo, Spain, while the beasts swam alongisde a glass wall, enabling the world to see the touching exchange.
The patient hippo put up with the calf - which was only a few months old - nipping at her and climbing all over her back, just like a boisterous toddler. And although the mother teased the calf, opening her mouth wide as though she was going to bite him, she did nothing more than give him a gentle nudge with her nose.
Philip, who now lives in the Spanish city, said: 'The hippos are kept in a large enclosure, with a glass wall at the zoo, and always seem very happy.
'It was the first time I had seen the calf there, but I believe he was about five or six months old. It was quite fascinating, the baby and mum were actually playing the whole time - something you don't expect hippos to do. The calf was swimming all round mum and occasionally nipping at her or standing on her back and mum would pretend she was going to bite the baby which is why her mouth was open.
'Mum seemed to pay no attention to the human onlookers but the baby sometimes came to the glass for a look and also sometimes played on its own popping up and out and down from the surface in a stream of bubbles - all very entertaining.'
The hippo is the third largest land mammal after the elephant and the rhinoceros and is native to Africa, where it stays cool during the day by remaining in mud or water before emerging in the evenings to graze on grass. They are under threat, however, from poachers because of their ivory teeth, and also through a loss of habitat. The animals can grow to be as heavy as nine tonnes but can still easily outrun humans. Hippos are also very aggressive and ill-tempered, particularly when it comes to defending their territory and their young. Such characteristics mean few predators - apart from humans - dare to target them.