“Trying to unravel what the common ancestor of animals as different as a squid and oyster looked ... were armoured spiny slugs, prior to the evolution of the shells that we see in modern snails ...

Buried alongside the mummies are statuettes, carvings, and castings made from gold, silver, wood, and spondyllus, a spiny oyster shell from the coast of Ecuador that was highly prized by the Inca.