Facts and figures

PUBLISHED : Friday, 11 June, 2004, 12:00am
UPDATED : Friday, 11 June, 2004, 12:00am

There are around 4,000 species of mammals but more than a million species of insects. Entomologists (a scientist that studies insects) believe that we've only discovered 10 per cent of the world's insect species.

Insects are one of the world's most successful organisms, which explains why they are almost everywhere.

Almost 40 per cent of known insect species are beetles.

The rare beetle titanus giganteus is the largest insect in the world. Some grow to more than 15cm long and can be found in the rainforests of Brazil and French Guiana. They could probably take off a person's fingers with their strong mandibles (mouth parts).

The largest cockroach is the giant cave cockroach, Blaberus giganteus, which reaches 10cm in length. Like all insects, they have a breathing system very different from ours. They don't have lungs - they have tracheae that run through their body. They have little holes on the side of their stomachs called spiracles to let air in and out through diffusion. Diffusion of air is a slow process, therefore it is impossible to have a human-size cockroach like the ones we see in movies, unless they somehow evolved lungs.

The programme will run at the weekends from July 19 to August 31. Please call 2526 4473 or download an application form from www.wwf.org.hk/eng/involved/public_visits/insect_watch.html. Applications must be made two weeks

in advance.