No man is a hero to his stomach. It is a source of comfort to the envious that geniuses are just as shackled by diet as the rest of us - just as chained to their own digestive processes. Take Charles Darwin (1809-82). No individual has done more to change our perception of the universe. He fathomed the origin of species from squid to dandelion, from cherry to ape. He understood "the descent of man" as it had never been understood. Yet he never got to grips with the rumblings and retchings in his own tummy, which tortured the poor man for more than half his life.
Darwin hadn't always had digestive troubles. As a lad growing up in a well-to-do Shrewsbury family, he displayed a foppish gusto for roast beef and partridge shooting. At Edinburgh University, where he studied medicine, he tucked into local stewed herrings and fried oysters. He resented lecture time because it cut into breakfast time; he yawned through lessons on the properties of rhubarb. If Charles had followed his father, Robert, into the medical profession, maybe he, too, would have become corpulent and complacent. Darwin senior weighed 330lb.
But it was not to be. At the age of 22, Charles was engaged as a naturalist on board HMS Beagle, circumnavigating the globe, a four-and-a-half-year journey that vastly expanded his knowledge of food, as well as changing the course of his entire life. In Bahia Blanco, he ate ostrich egg dumplings (actually rhea) and roast armadillo, noting that armadillos, "cooked without their cases, taste and look like duck". Agouti, a large chocolate-coloured rodent, was "the very best meat I ever tasted". On a trek to Buenos Aires, he ate like a gaucho, "nothing but meat" roasted over a fire. He downed mate tea like a native. The tropical fruits of Tahiti amazed him - bread-fruit, pineapple and guava. …