Along the coast of Japan there are a group of divers well known for collecting pearls. A majority of these divers are women and are called ama, meaning ‘sea woman’.

According to Herman Rahn and Tetsuro Yokoyama, authors of "Physiology of Breath-hold Diving and the Ama of Japan," the Japanese practice of ama may be 2,000 years old.

Traditionally, and even as recently as the 1960s, ama dove wearing only a loincloth. Even now, ama dive without scuba gear or air tanks, making them a traditional sort of free-diver.

While ama are mostly known for pearl diving, they originally dove for food like seaweed, shellfish, lobsters, octopus, sea urchins and oysters (which sometimes have pearls).

Ama can keep diving well into old age. The older divers are generally able to stay submerged longer than the younger. Unlike other traditional crafts, there is no formal apprenticeship system of training for ama divers. While diving skills such as breathing techniques can be acquired relatively easily through practice, the most valuable knowledge, the best places to find abalone, are a closely guarded, even between mother and daughter divers.

A photo by Japanese photographer Iwase Yoshiyuki from his series on ama divers next to Mie Hama from the Bond movie "You Only Live Twice" where she plays an ama woman who makes a living by diving for shells, while also working for the secret service.