Apart from his collection of 100,000 shells, Chang Yi-hsien is also a master of keeping living mollusks. The biggest and reddest shell pictured, a Rumphius' slit shell, was originally his museum's star attraction. It has since been sold to the National Taiwan Museum. (Jimmy Lin)

Some 570 million years ago, in theCambrian period, nearly 400 million years before the dinosaurs appeared, Rumphius' slit shells were quietly crawling at a depth of 200 meters near Kuishan Island off the Ilan coast. These living fossils have been crawling there ever since.

Chang Yi-hsien, who hails from a long line of fishermen, works in Nanfang-ao harbor in Ilan and has Taiwan's largest collection of shells. Eleven years ago, he became the only person in Taiwan to successfully keep a living Rumphius' slit shell.

Chang has more than 100,000 shell specimens in his collection, including common nautiluses (Nautilus pompilius); Teramachi's cowries (Cypraea teramachii) and Joyce's cowries (Cypraea joycae), which can be worth as much as a car; and Rumphius' slit shells (Entemnotrochus rumphii), which appeared on the planet earlier than the dinosaurs. He also keeps more than 30 different species of mollusks in aquariums. They are so precious to him that he often sleeps next to the tanks. He set his personal record at the Ilan Green Expo, when he slept beside them for two months.

To find how Chang's fate became interconnected with mollusks, one has to go back in time and consider the actions of his father, Chang Fu-chuan.