When most people think of science, sex usually isn't the first thing on their minds. Yet there are researchers out there dedicated to understanding one of the most basic biological processes in both humans and animals alike.
In this roundup, explore the most interesting stories related to the science of sex that Discovery News published this year.
1. Sea Squid Are Same-Sex Swingers
Given all the limbs that they have, you'd expect squid to have interesting sex lives.
Observations of sea squid mating in the deep sea revealed that males are just as likely to couple with females as they are with each other, as reported in September in the journal Biology Letters.
Squid observed in this study, Octopoteuthis deletron, have large eyes and light-producing organs in their skin. So, it's unlikely that they're simply mistaking males for females and low depths. Rather, these squid tend to live solitary lives and likely take every chance they can get to mate.
Last year, we found out that humans and Neanderthals mated. This year we learned exactly what some humans walking the Earth today inherited from their Neanderthal ancestors.
Mating with Neanderthals improved our health, according to research presented to the Royal Society in London, by giving early Homo sapiens disease resistances that they wouldn't otherwise have had.
Neanderthal-human interbreeding may have been rare, according to a study published in September in the journal Proceedings of theNational Academy of Sciences. But it occurred frequently enough and their descendants were successful enough that traces of Neanderthal DNA show up in the genes of all non-African humans alive today.
3. Beetles Die During Sex with Beer Bottles
The sight of a beetle having attempting to mate with a bottle may be funny to any outside observer, but it's fatal for these little insects.
Male Australian jewel beetles can't tell the different between the smooth, brown, dimpled surface at the bottom of a beer bottle and a female of their species.
It's not the attraction, but rather the persistence that kills the males as they fruitlessly endeavor to consummate the union and overheat under the sun in their effort.
4. 40-Million-Year-Old Sex Act Captured in Amber
In this photo, you'll see what might be the longest-lasting sexual encounter in history.
Forty million years ago, a female mite overpowered a prospective partner and began to mate. Just as that as happening, as reported by Discovery News' Jennifer Viegas, a dollop of tree resin fell on the couple, sealing them together forever.
5. Spiky Animal Doesn't Practice Safe Sex
You'd think that an animal covered in spines would pay extra attention to safety measures during the course of mating. Echidnas, a spiky, egg-laying mammal that's widespread in its native Australia, apparently isn't that cautious.
According to research by Gemma Morrow from the University of Tasmania, these animals frequently engage in group sex. Males will also also attempt to sneak up on hibernating females and mate with them.
Part of this -- let's call it gusto -- for frequent mating in groups and at odd times may be because females don't reproduce every year, according to Morrow.
A little overconfidence can make a big difference for men looking to attract a mate.
A study published this month found that men who overestimate their own appeal to attractive women tended to be more likely to achieve their goal of winning the approval of a prospective partner.
Women, by contrast, tended to undervalue their own physical appeal, according to the study.
7. The Playboy Gene: Promiscuity Can Be Inherited
If sex is on your mind all of the time, it might not be your fault. It turns out that, according to a study published in the Proceedings of the National Academy of Sciences in June, promiscuity can be inherited.
In fact, the tendency to fool around could be locked into our genetic code. And it appears that many monogamous animals, not just human, cheat.
Despite its social and potentially emotional drawbacks in humans, promiscuity has its advantages evolutionarily-speaking, since it can result in more offspring and greater genetic diversity.
8. Chimps Have Better Sex Than Humans
If the chimpanzee in this photo looks like he doesn't have a care in the world, it's for one simple reason: He's having better sex than you.
It's nothing personal. These primates have been shown to have more pleasurable mating experiences than humans, according to a study published in the journal Nature in March.
The reason is actually anatomical: Male chimps have spines on their penises that increase stimulation during sex for both sexes. There is a major drawback for these primates, however: Female can get injured in the process.
9. Monogamous Animals Often Have Unattractive Partners
Some monogamous animals may be born with the "playboy gene." Others, however, are inclined to stick with the same partner.
Those that do choose to remain with a single, special someone probably all share one trait in common: They settled for partners who are typically unattractive.
Although relationships may provide security given a lack of options, according to the study conducted on zebra finches and published in February in the Proceedings of the Royal Society B, these pairings could raise the stress levels of the partner that took what he/she could get.
What lonely space geek hasn't watched a particularly revealing episode of Star Trek and thought that sex in space with some alien babe would be pretty darn neat.
Leaving aside the sexual compatibility of a member of either gender of a yet-undiscovered extraterrestrial species, the idea of sex at zero Gs might sound appealing in theory. In practice, however, it's a much different matter. (According to NASA, however, sex in space hasn't yet been done and certainly isn't on their to-do list.)
Without traction, copulation doesn't really work. After all, what is the act of sexual intercourse without friction? Sex also would require extraordinary coordination of the (at least) two free-floating bodies.
Although sex in space may seem like non-essential given the missions astronauts are sent on today, future missions that require a commitment of years or even decades will likely be faced with this issue. After all, a crew comprised of adults of both genders isn't going to just sit around and watch the stars all day.