Jika-tabi shoes in some industries, many workers prefer them for the softness of their soles. This gives wearers tactile contact with the ground, and the concomitant gripping ability lets them use their feet more agilely than rigid-soled shoes allow. This is useful for workers who traverse girders on construction sites and need to be sure what is under their feet. Carpenters and gardeners wearing these boots can, if they wish, use their feet as an extra pair of hands, for example to hold objects in place. There is also a line of knee-high all-rubber jika-tabi that is used by workers in
Supernumerary body part Supernumerary body part Supernumerary body parts are most commonly a congenital disorder involving the growth of an additional part of the body and a deviation from the body plan. Body parts may be easily visible or hidden away, such as internal organs. Many additional body parts form by the same process as conjoined twins: the zygote begins to split but fails to completely separate. This condition may also be a symptom of repeated occurrences of continuous inbreeding in a genetic line. Specific types of additional body parts include: Vestigial structures are anatomical structures of organisms in a species which are