Monogamy is rare in the natural world and staying faithful is a struggle for most animals. While many humans opt for a solitary life partner (to make our Netflix and chill evenings a little less sad and lonely), the majority of species in the animal kingdom shack up with multiple companions. Even those that do pair for life are often guilty of getting a little something on the side or ditching their soul mate when the sex dries up.

There are, however, a small number of species that make a long-term commitment. So if thoughts of settling down with The One are floating around in your head this Valentine’s Day, here’s some inspiration from the natural world.

Pol(VOLE)ting into love

The water vole is a close relative of the priarie vole. Image © Peter Trimming

It’s hardly surprising that “vole” is an anagram for “love” – when prairie voles fall, they fall hard. Unlike most rodents, these bucktoothed burrowers pair up for life (albeit a short one), opting to nest together and share the responsibilities of raising young. An almost-fanatical desire to be together helps ensure that they successfully breed as much as they can during their year or two of life in the harsh, resources-limited grasslands of the US and Canada. Sticking together gives them a better chance of finding enough food and raising heaps of mini-voles.

But it’s not loneliness that fuses the lovers together. Certain brain chemicals – possibly released during mating – play a crucial role in forging a strong bond. Of course, no vole is perfect and some have been known to partake in occasional bouts of opportunistic infidelity. Love is complicated.

Send me your dik-dik pics

Monogamy is a fairly loose term in the animal kingdom and many species that are socially monogamous have a tendency to mate outside the pair-bond (players gonna play). But the Kirk’s dik-dik – a tiny antelope from eastern and southwestern Africa – believes in true love. Research shows that dik-dik couples pair-bond with little evidence of any romantic rendezvous outside of their relationships.

Before you gush at their devotion to one another, though, studies also indicate that the males can be very possessive. Females likely avoid any extra-copulatory action because their partners don’t allow it. Males keep watch over females even when they aren’t in oestrus and will chase off any other potential suitors. Curiously, the males don’t contribute any parental care, so it’s not fully understood why lady dik-diks tolerate the males’ clinginess. Researchers hypothesise that mating skirmishes can be violent and the females prefer to have the males around for protection (even if the blokes don’t understand the concept of giving their partner some space). Talk about putting the dik in dik-dik.

Once you go black vulture you never go back

Image © Mdf

About 90 percent of all birds are socially monogamous, living and raising chicks together, but they typically have more than one sexual partner (best not to put all your eggs in one basket, right?). Faithful they are not, but some birds, like the black vulture are big on family and frown upon infidelity. Mommy and daddy vulture share the responsibility of feeding and caring for youngsters and chicks may be partly dependent on both parents for several months after fledging. Family ties are stronger than in some other species and if any bird boinking happens outside of the pair bond, the vultures will attack the fraternising interloper.

Leave it to beavers

Image © Pixabay

Much like dik-diks, beavers remain faithful once they’ve found that special someone. A research team working in Russian analysed the genetic makeup of the region’s beaver colonies and discovered that all of the offspring studied came from loyally committed parents. None of the kits had been fathered by other males suggesting that European beavers do right by their pair-bonded partners. The same can not be said for their cousins from America. Despite the fact that American beavers are closely related to their European counterparts and the species share similar ecology and lives, the US beavers are notorious cheaters.

Of course, sneaking around does have its advantages. If a female mates with a healthier male than her primary partner, she gains better genes that she can pass on to her young. But there are downsides too. "Genetic monogamy lowers the risk of parasite transmission," study author Pavel Munclinger from Charles University in Prague told the BBC. "It also lowers the risk of partner desertion, which is very important in species with extensive parental care of both sexes." For American beavers, the risk is obviously worth it.

Big bad wolves

Image © Pixabay

For grey wolves, or at least for members of packs living in Idaho, monogamy has an expiry date. Alpha males and females form strong pair bonds, but research shows that for most couples the spark fades after about two years. Once the honeymoon phase is over, wolf pairs may part ways. It’s not entirely clear why the canines break up, and it seems to be detrimental to their pups who are more likely to survive if the parent wolves figure out their differences.

David Ausband, author of a study on monogamy in Idaho’s wolf packs, suggests that it could have something to do with the turbulence and dynamism of wolf social life. “There is more drama in a wolf pack than in a middle school dance. There is always stuff going [on],” he told the Spokesman-Review. It may also have something to do with the size of the pack. Larger groups are harder to control, resulting in philandering and an increased occurrence of “sneaker males” (males that mate with female pack members and then take off, ditching their parental responsibilities). For the most part, wolves are monogamous, but like many other mammals true monogamy remains elusive.