The roots of sexual differences : why male and female animals differ
Elephant seals : harems, hierarchies, and giant males
Great bustards : gorgeous males and choosy females
Shell-carrying cichlids : protective males and furtive females
Yellow garden spiders : sedentary females and roving males
Blanket octopuses : drifting females and dwarf males
Giant seadevils : fearsome females and parasitic males
Bone-eating worms : female tubeworms with harems of minuscule males
Shell-burrowing barnacles : sac-like females with harems of phallic males
The diversity of sexual differences : differences between males and females across the animal kingdom.