The Barnacle Goose: The Medieval Bird That Was Believed to Grow on Trees
For some five hundred years, sober and learned Europe believed in a bird that had no parents. The barnacle goose —the handsome black-and-white goose that winters in vast flocks on the coasts of Ireland and Britain—posed the medieval mind a genuine problem: no one had ever seen its nest . It arrives each autumn out of the northern sea-fog and departs each spring into it; no eggs, no goslings, no breeding grounds were known (they lie, we now know, on the cliffs of Greenland and Svalbard, beyond the medieval world's entire map); and nature, the age reasoned, does not spawn from nothing. The answer stood visibly on every tideline: the goose barnacle —the strange stalked shellfish that clusters on driftwood, whose feathery black-and-white cirri, protruding from the shell, look uncannily like a folded bird. The conclusion was drawn, written, illustrated, and defended by the best authorities of three centuries: barnacle geese grow —from the barnacles, which grow on timber rotting in the ...