In the total truth, harvestmen are not venomous, and are not a threat to humans in any way. However, there is one characteristic of theirs that might freak some people out. When a harvestman is attacked by a predator or is startled, it will simply lose one of it's long legs. But, to ensure the actual harvestman stays alive, it uses another method. After it's leg falls off, it just continues to twitch. This happens thanks to the "pacemakers" found at the base of their legs, which send electrical signals that tell the muscles in the leg to continue to contract and relax in a rhythmic pattern. Although the legs of most species only twitch for about a minute, other species' legs have been clocked to twitch for about an hour before stopping.