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satellite male is focused on stealing one particular male’s harem. It looks for all the world like envy to me, but I know it’s impossible to know for sure until controlled experiments are done.
    The really interesting thing about the harem mating system in sac-winged bats is that everybody is cheating. In a frenzy of paternity analysis that would make Maury Povich envious, researchers learned some dirty sac-winged secrets. Yes, harem males fathered more of the pups than satellite males did, but a harem male was the father of only about 30 percent of the pups in his own harem. Thirty percent! The other 70 percent came from a mix of nearby satellite males and a few males with harems of their own, whom females had obviously gone out to visit from time to time.
    Harems are common in nature, and that makes life pretty tough for the males out there who just can’t compete with other males. But there’s an alternate strategy available: if you can’t beat ’em, become a sneaker male. Sneaker males occur in all kinds of different animals, and their strategy is to avoid confrontations with the stronger males by getting creative.
    Great Plains toads mate in the puddles that form after a big storm in the midwestern Unites States. Males initiate this process by getting into the water and croaking out into the night, to say, “The water’s fine, ladies. You should come join me!” 17
    One thing about frogs is that the male has no penis to place inside a female. Instead, he’ll hold on to her in the water, hugging her from behind in a sort of frog cuddle. IV While he does that,she will release her eggs into the water as he releases his sperm on top of them. That is how frogs have sex, but first they have to meet up.
    A female Great Plains toad won’t approach just any croaking male. She prefers a large male, and there’s a biomechanical link between how big a toad is and the pitch of its voice: bigger toads have deeper voices. So by calling out with a deep, booming voice, a big toad can advertise his size. This sort of screws the little males over, since their tenor tones just don’t impress the females, and there’s no way to fake a deep voice. (No matter how well you play a trumpet, it will never sound like a tuba.)
    The solution? Small males hang out near a dominant male and don’t croak at all. When a female swims over to join the deep-voiced male, the sneaker male intercepts her, and they cuddle.
    It’s not clear whether the female thinks he was the one calling, whether it’s a case of forced copulation, or something else, but one thing is certain: it works. Sneaker males fertilize eggs, and although it’s not as effective as being a dominant male in terms of number of eggs fertilized in a season, it’s a work-around that allows small frogs to pass on their DNA.
    Another sneaker male strategy has been described for a frog living high in the mountains of Spain. 18 There, a sneaker male will find a cluster of eggs floating around in the water that have already been fertilized. With the parents long gone, the sneaker male grabs the floating mass of eggs using the same body posture that a male typically uses when grabbing a female. Then he releases his sperm onto the eggs. Paternity analyses have revealed that around one-quarter of the frog embryos in a pond had sneaker dads who used that strategy. Again, it’s better to be adominant male, but just because you can’t play with the big kids doesn’t mean you’re out of the game.
    Oh, we’re not done with sneaker male frogs yet, though. There’s a toad called Rhinella that is commonly found in little ponds next to streams that appear after a good rain in the Amazon. 19 When those ponds appear, hundreds of Rhinella toads will go there to mate, and thousands of eggs will be laid in the course of two or three days. Because that time span is so short, competition among males is ridiculously intense, and many of the females end up getting injured or killed in the fray.