Off the wall

There's no limit to the things people do to get themselves on television. A teenager, for instance, will count how many licks it takes to get to the centre of a Tootsie Roll Pop, no doubt some form of popular American confectionery. Her tally is 1,097.

The Things People Do (Star World, 7.30am) is a new series that makes entertainment from such odd ambitions.

An unemployed construction worker is another case. He employs a bank of telephones and auto-diallers to ensure he gets on every radio contest going, and makes a living from his winnings.

The series also features monuments to strange human foibles. Every day numerous people walk away from their luggage when leaving airports. The town of Alabama has become the lost luggage capital of the world. Unclaimed baggage gets stored in a giant warehouse before being auctioned to local residents.

This Friday several thousand Hong Kong people will set off on their own crazy challenge, spending up to 48 hours hiking some of our most forbidding mountains. Tackling the 100-kilometre Maclehose Trail is one thing. Doing it without two nights' sleep should qualify for an appearance on the Star series.

The Trailwalker event, which raises money for Oxfam Hong Kong, is featured in Hong Kong Connection (Pearl, 6.50pm). A Gruelling Trail follows previous teams as they enjoy their annual dose of glorious masochism and demonstrate that there is more ambition in Hong Kong than the mere making of money.

What is it that makes women more likely than men to be ready to spend a life among the great apes? Learning From The Great Apes (National Geographic, 8pm) profiles the work of the three most remarkable names in primate research - and they are all women.

Jane Goodall has been studying chimpanzees in Tanzania since the 1960s while Birute Galdikas focuses on Indonesia's orangutans. Dian Fossey, who was killed by poachers while working with mountain gorillas in Rwanda, is also remembered.

These women, often known as the Three Angels, have inspired a new generation of females to continue their research, which requires such feminine qualities as endless patience and close observation.

This programme looks at the reasons for their calling and how their research is revolutionising our understanding of these animals and their close relationship with our own species.

Hunters (Discovery, 8pm) profiles the gruesome things animals do, revealing the survival strategies of powerful killers in the animal kingdom, from the largest carnivores to deadly vipers and the tiniest of insects.

This week's episode, The Giant Grizzlies, shows how brown bear cubs in Alaska must make the most of short summers to forage and hunt. But for their survival, they depend on their mums to save them from the anti-social violence of the male, bear or otherwise.