Natural World: Great White Shark – A Living Legend (BBC2, 8pm)

STRANGE the things you learn from television. And in the most unlikely places.

The Natural World documentary reveals how tommy sharks got their name.

It followed the sinking of a British troop ship, HMS Birkenhead, off Cape Town in 1852. There were only three lifeboats, so the captain gave the order, “Women and children first” – the first time this procedure was used.

The ship sank in 20 minutes, leading to the death of around 400 people. Many were taken by sharks and, as British soldiers were known as Tommies, the name started to be used in relation to these predators.

In fact, most of the casualties died not through being eaten, but from exhaustion and the coldness of the water.

This fact-finding is a bye-product of the programme’s main concern, South African naturalist Mike Rutzen communicating with sharks. He reckons they’re the most misunderstood animal on the planet and wants to rescue their reputation by swimming with sharks.

Anyone who’s ever seen Steven Spielberg’s film Jaws will think him mad. But he never saw the movie when he was younger, so didn’t have the fear the great white shark’s activities on screen instilled in viewers.

His fascination, love almost, of sharks began with an accidental encounter in 1990. He was underwater, looking in a crevice when a shark popped out. He’s been attracted to them ever since.

His first job, as skipper on a shark cage fishing boat, meant he spent several hours a day with them. Now he wants to take his relationship to a higher level and swim with them.

He finds sharks respond to his body positions, which he uses as a language to “speak” to them. Body postures and movements are used to signal intentions.

Rutzen believes he’s safe if he does the same.

His theory seems to work, as scenes of his swimming alongside great white sharks demonstrate. The creatures seem able to distinguish between him and food.

This is comforting when you see amazing scenes of sharks jumping out of the water at 30mph to catch prey.

Morecambe & Wise: The Show What Paul Merton Did (BBC1, 9pm)

IT was all the way back in 1941 when Eric Morecambe and Ernie Wise first took to the stage together.

Throughout their long career they worked with many famous names, including Paul McCartney, Alec Guinness, Diana Dors, Derek Jacobi and Laurence Olivier. The number of stars who wanted to work with them was a testament to their popularity.

In this hour-long special, Paul Merton hosts a celebration of their career, combining nostalgic tributes from their peers with comments from contemporary performers they have influenced.

The programme also delves into the archives to reveal some of the comedy partners’ greatest moments.

Prog Rock Britannia – An Observation in Three Movements (BBC4, 10pm).

IT would soon become one of the most maligned genres in rock history, but back in the early 1970s, earnest music fans across Britain were swept up by prog.

For anyone too young to remember, progressive rock grew out of late Sixties psychedelia, and was known for its complex structure, technical virtuosity and literary influences.

This feature-length documentary gives fans the chance to relive the glory days, when bands such as Yes and Genesis ruled the world, while also looking at how punk, over-ambition and the eventual commercialisation of the music would eventually lay the style low.