sentences:  The physiological impacts of cannibalism on male fitness include his inability to father any offspring if he is unable to mate with a female.There are males in species of arachnids, such as "N. plumipes", that sire more offspring if the male is cannibalized after or during mating; copulation is prolonged and sperm transfer is increased.In the species of orb-weaving spider, "Argiope arantia", males prefer short copulation duration upon the first palp insertion in order to avoid cannibalism.