The Problem of Energy

As a child, I read Friday by Robert A Heinlein, which portrayed a future in which energy needs are addressed by energy storage devices called "Shipstones", which are described as a way to pack more kilowatt-hours into a smaller space and a smaller mass than any other engineer had ever dreamed of. To call it an "improved storage battery" (as some early accounts did) is like calling an H-bomb an "improved firecracker." In the novel, the Shipstone's eponymous inventor realised "that the problem...

 Guppies Evolve Their Spots in Experimentation

Guppies are popular freshwater aquarium fish. As with the pheasants we met in Chapter 3, the males are more brightly coloured than the females, and aquarists have bred them to become even brighter. Endler studied wild guppies (Poecilia reticulata) living in mountain streams in Trinidad, Tobago and Venezuela. He noticed that local populations were strikingly different from each other. In some populations the adult males were rainbow-coloured, almost as bright as those bred in aquarium tanks. H...