... snatchedfrom the jaws of death in the nick of time. The would-be victim and the courage of the rescuers are applauded by all, and justifiably so, for this is the stuff of leg-2 THE BIOLOGY OF HUMAN ... example is the effect of the insecticide DDT on the loss of durability of the eggshell of predatory birds, such as the bald eagle (Carson, 1963). Overuse of DDT after World War II threatened their ... mam-mals, the great cetaceans, so spectacularly adapted for life in the sea, are confinedto the surface layers of the ocean. The crushing pressure of the seawater, the cold,and the darkness make the...