Valerio Sbordoni

Much of Valerio Sbordoni's work has been carried out in southern Mexico, where he has searched for life forms in the remote caves and sotanos (giant potholes) of Chiapas state. Mexico

This aerial view of the Sotano de la Lucha shows the forest canopy both within and around the hole clearly. Mexico

The spectacular sotanos can reach depths of 350m and only expert speleologists can risk exploring them. Mexico

Sbordoni has led, or taken part in, 31 expeditions to explore life underground in more than a dozen different countries.

In one sotano alone Sbordoni found 42 species of butterflies. He is coauthor of the encyclopaedia Butterflies of the World and has published over 250 articles and seven books.

Sbordoni is interested in more than just life underground. He photographed this grasshopper in the forest canopies of a sotano.

Sbordoni catches a beetle carrying a pseudoscorpion. The sotanos are home to many little-known species.

Sbordoni's heart remains in the field. With his numerous expeditions, he has contributed extensively to the discovery of cave-dwelling creatures in the tropics.

To date, Sbordoni has discovered more than 150 species of hitherto unknown cave-dwelling creatures. Sbordoni believes that many of these species, retreated undergound millions of years ago to avoid extinction and adapted to unique conditions far beneath the earth's surface.

Valerio Sbordoni , pictured in an artificial cave, is a biologist, zoologist and speleologist who has explored caves for over 35 years.

Sbordoni tests his new theories on biodiversity and species evolution in his laboratory. Mexico