polyandry

It's almost a given that, during any discussion about male infidelity, someone will throw out some variation of "men are biologically programmed to spread their seed." Why is there this theory that men are more driven to cheat? Part of it has to do with the size of their gametes. If bigger is better, then men are pathetic, for their little sperm are 1/100th the size of a woman's egg. Because women have such a greater investment in each offspring right from the get-go, the assumption is that women are pickier when it comes to who they allow to fertilize their eggs. Men, since it doesn't cost…
Benjamin Franklin once quipped, "Where there's marriage without love there will be love without marriage." His affairs are well known in American history, however this founding father may have been stating a truth extending to evolutionary history as well. Christopher Ryan (author of the forthcoming Sex at Dawn) offers some thoughts on the role of novelty in the sex lives of our favorite primate. He suggests that men are drawn to variety in sexual partners while women are drawn to variety in technique: When researchers decided to look at this issue to develop a Sexual Boredom Scale, they…
You've got to feel sorry for the female seed beetle. Whenever she mates with a male, she has to contend with his spiked, nightmarish penis (remember this picture?). And despite the damage that it inflicts, one liaison just isn't enough; female seed beetles typically mate with many males before they lay their eggs. Surely, she must benefit in some way? The most likely idea is that she somehow ensures that her eggs are fertilised by sperm from males with the "best" genes - those that either make for particularly fit and healthy young, or that are a compatible match for the female's own genes.…