When the botanist Richard Deakin examined Rome’s Colosseum in the 1850s, he found 420 species of plant growing among the ruins. There were plants common in Italy: cypresses and hollies, capers, knapweed and thistle, plants “of the leguminous pea tribe,” and 56 varieties of grass. But some of the rarer flowers growing there were a botanical mystery. They were found nowhere else in Europe.
To explain this, botanists came up with a seemingly unlikely explanation: These rare flowers had been brought as seeds on the fur and in the stomachs of animals like lions and giraffes. Romans shipped these creatures from Africa to perform and fight in the arena, and as Deakin takes care to mention in Flora of the Colosseum of Rome, the “noble and graceful animals from the wilds of Africa … let loose in their wild and famished fury, to tear each other to pieces”—along with “numberless human beings.” As the animals fought and died in the arena, they left their botanical passengers behind to flourish and one day overtake the building itself. {read}