Family business: Abbie Usher and her father, Daryl, take their traveling museum on the road. (Jennifer William/AQ) At Saturday’s Esoterica market in Fredericton, between the dark art and the tattoo artists, one table had a mermaid named Darwin. He isn’t the Disney kind. Darwin is a Fiji mermaid, a sideshow classic in the style P.T. Barnum once exhibited, and he is the favourite piece of Abbie Usher, 23, who runs the traveling museum Typical Relics. “We’re a traveling museum t