On Food and Cooking

air, and run them on the energy in sunlight.
Animals, on the other hand, can’t extract
energy and construct complex molecules from
such primitive materials. They must obtain
them premade, and they do so by consuming
other living things. Plants are independent
autotrophs, while animals are parasitic
heterotrophs. (Parasitism may not sound
especially admirable, but without it there
would be no need to eat and so none of the
pleasures of eating and cooking!)
There are various ways of being an
autotroph. Some archaic bacteria, which are
microbes consisting of a single cell,
manipulate sulfur, nitrogen, and iron
compounds to produce energy. The most
important development for the future of
eating came more than 3 billion years ago
with the evolution of a bacterium that could
tap the energy in sunlight and store it in
carbohydrate molecules (molecules built from
carbon, hydrogen, and oxygen). Chlorophyll,