For some animals getting it on can be hard work and even downright dangerous.
Male Túngara frogs woo females with a call that is so full of energy and passion, it creates ripples on water. Bat predators listen for the calls, hoping for a frog dinner.
"When a bat flies by, the frog's first line of defense is to stop calling," Rachel Page, a scientist with the Smithsonian Tropical Research Institute. "But the water ripples continue for another few seconds, effectively leaving a detection footprint for the approaching bat."
Male wolf spiders give new meaning to "bust a move." They have an amazing tap-dancing courtship routine that drives females wild. But biologist David Clark of Alma College found that other males watch and try to out-dance their rivals. While all of this is going on, birds and other predators can better detect the distracted spiders, and might eat away the whole show.
Male peacocks have such a flashy courtship dance that adoring females come from far and wide to watch. Unfortunately, jackals, tigers and hawks often come too and may eat the birds.
Veery, a small bird, has a beautiful, flute-like mating song. But it often has to be "veery" quiet to avoid being heard by owls that stalk the little singers.
Male mice and rats are actually very romantic, singing very complex long songs for their sweethearts. Humans can actually sometimes hear the flirtatious rodent communications, alerting them that their home has rodents.
Kerstin Musolf, a researcher in the Konrad Lorenz Institute for Ethology at the Austrian Academy of Sciences, told Discovery News that people usually hear the "beginning of courtship" among rodents, which can sound like little squeaks. Sadly for the rodents, irate homeowners might next call in an exterminator.
What would a list like this be without sexual cannibalism?
Black widows are notorious for mating and then eating their mates. Males are so afraid of females that they shake their abdomens to produce vibrations mimicking those of spider predators, Simon Fraser University biologists recently found. Instead of trying to attract a mate in this case, males are happy to repel females.
Female Chinese mantis insects will sometimes eat their mates even as copulation is taking place. Particularly hungry females will tend to do this more.
As for why sexual cannibalism exists, some researchers theorize it prevents females from dying, which would also clearly stop females from reproducing and passing on the father's genes to the next generation.
Females of the Australian redback spider demand 100 minutes of courting, or else they usually cannibalize their male suitors, Matjaz Kuntner, an evolutionary biologist at the Slovenian Academy of Sciences, told Discovery News.
Males of this species are also known to mate and then literally somersault themselves into the mouths of their female partners, who happily eat them.
Komodo dragons, along with boa constrictors, rainbow boas, various shark species, and even domestic turkeys, can all give virgin birth.
They're on this list because the process, parthenogenesis, isn't great for genetic diversity. It's a last ditch effort to repopulate when no mate is around.
Most animals work hard to attract mates. The female anglerfish, however, hopes hers will go away. Males latch onto the females like a parasite, consuming the female's food and benefiting from all that she does. Only later do the males fertilize her eggs.