Does it pay to be a lover or a fighter? The answer can depend upon the situation, of course, but some animals have evolved a greater tendency to war or woo, suggests a study in the latest issue of Nature Communications.
Senior author John Fitzpatrick, a lecturer on animal evolution at The University of Manchester, and his colleagues studied over 300 species and found that elephant seals are definitely more fight-prone.
"In groups like pinnipeds, in some species, like elephant seals, males are able use their investment in weapons -- in this case extremely large body size -- to keep rival males away from females and there is a trade off between investment in testes and weapons," he explained. "Essentially, the largest pinniped species have the smallest testes, i.e. they are fighters, rather than lovers."