Harvestmen will readily release a leg that has been grasped by a predator. Apparently they do not grow back.
The second pair of legs is especially important for obtaining knowledge of the environment,
so the loss of one or both of those legs can be a problem. However, the loss of a leg or two doesn't
seem to slow them down much, so it's a great alternative to being eaten--legs and all.
However, with only five legs left, this guy is clearly on shakey ground.