• John Sparks
  • Leo Smith, doing fieldwork in Madagascar

Leo Smith, who’s been an assistant curator of zoology at the Field Museum since 2007, has spent the last several months working on the upcoming exhibit “Creatures of Light: Nature’s Bioluminescence,” which opens this Thursday. Smith studies the evolutionary biology of fishes, particularly venomous and bioluminescent ones. He talked to me recently about bioluminescent animals, both the ones in the museum exhibit and the fishes he studies. This is part one of a two-part series; below, Smith discusses the “Creatures of Light” exhibition, the difference between bioluminescence and biofluorescence, and how male anglerfish become parasitic when they meet females. Smith, in his own words:

It’s not obvious what [bioluminescence] is for. In some groups it is, like the anglerfish: they’re obviously primarily using it to attract prey. All the animals are attracted to the light. They’re also probably using it for attracting mates. The male’s a little tiny parasite, and will hunt out the female and actually attach—some species permanently, some semipermanently—and her blood will start passing through the male. On the ones that permanently attach, the [males] lose their brains; they lose most of their nerves. And the females can have eight or nine of these attached.