UC Davis' Bohart Museum of Entomology has television's Fear Factor to thank for the donation of some 30 to 40 Madagascan hissing cockroaches, left over from one of the show's outrageous stunts.

The roaches are now part of the museum's 30-year-old collection of hissing cockroaches.

The insects are among the world's largest roaches, measuring 2 to 3 inches long and an inch wide, about the size of a small mouse.

Hissing cockroaches (Gromphadorhina portentosa) are native to the island of Madagascar off the east coast of Africa. The roaches hiss when disrupted or threatened, by forcing air through a pair of modified abdominal spiracles, or pores, which are part of the insect's respiratory system. Male roaches also hiss during courtship and mating.

-- Kathy Keatley Garvey, UC Mosquito Research Program