The movement occurs in milliseconds, too fast for the human eye to process. To the naked eye, it appears as if the cockroach has disappeared.
“It was a serendipitous discovery,” said Robert J. Full, an integrative biologist at the University of California, Berkeley, and an author of the study, which appears in the journal PLoS One. “We were actually studying how these animals cross gaps.”
Brian McRae, a Berkeley undergraduate who is also listed as an author, was working on the project and noticed that the cockroaches disappeared at the end of a ledge.
A closer look at video recordings revealed that they ran full speed toward the end and then dived off, grabbing the edge with their claws (at times using a single leg).
This may be why “sometimes when we’re chasing them they are just gone,” Dr. Full said.
The group also looked at geckos and found that they exhibited the same behavior, using their own hooklike toe pads.
The researchers have now joined forces with Ron Fearing, a computer scientist at Berkeley, to try to develop a robot with the agility of a cockroach. A team of graduate students has built a working prototype with six legs.
“We don’t have the robot agility to really make robots as useful as they could be yet,” Dr. Full said. “This is a demonstration of that agility.”
Another way to make cockroaches disappear is to call Steve Gustafson, the magician of extermination for cockroaches.