Nothin’ but mammals: What wild animals show us about courtship, love and affection

Homo sapiens of the American persuasion plan to spend $26 billion on Valentine’s Day gifts this year, an outpouring of resources signaling love, devotion, desire and financial fitness.

While the form may seem evolved – cards, expensive chocolates, amorous vacations – the parallels to our animal brethren lie close beneath the blushing surface. As we celebrate Valentine’s Day, several Pacific Northwest species are also wooing mates in hopes of furthering their genetic line.

Case No 1? Wolves.

“Valentine’s Day is kind of the peak of the mating season for wolves,” said Ben Maletzke, a wolf biologist for the Washington Department of Fish and Wildlife.

The timing isn’t the only parallel. Like humans, wolf parents mostly raise their children together, with 2019 research from the University of Idaho suggesting the longer wolf couples are together, the more likely their offspring are to survive into adulthood. The evidence further refutes the adage “lone wolf.”

In general (and there are always exceptions in biology), a stable wolf pack will have only one mating pair, Maletzke said. Thus, young wolves looking to sow their oats must either leave the pack and try to establish their own pack with a willing partner, or challenge the dominant male or female wolf for the right to breed. Alternately, if the dominant wolf dies, the younger wolf may try and fill their spot in the hierarchy.

In Washington’s Cascade Mountains, where there is plenty of unclaimed wolf habitat, the newest packs are formed by dispersers. In northeast Washington, where the majority of the state’s wolves live, the competition for available space is fiercer.

“The social dynamic they have it’s very much similar to people and a family group,” Maletzke said. “You think of a teenager going off to college when they graduate high school, you’re never sure where they will end up. Some end up back with mom and dad.”

Wolves are rather rare as far as mammals go.

According to some research, only 3% of all mammals are monogamous with the vast majority mating when and with whomever they get the chance. Even more important for definitional purposes, most male mammals don’t help raise the young. Cervids – deer, elk and moose, for instance – aren’t monogamous. In the fall, when the females are in estrus, the males are on the prowl. Once the mating season, known as the rut, is over, they have nothing to do with the offspring, returning to spending the majority of their time with other males.

“They don’t bond and males will mate with as many females as they can, I’ve seen male fawns try to mount their moms,” said Melia DeVivo, an ungulate research scientist with the Washington Department of Fish and Wildlife. “Probably not the romantic story you were hoping for.”

If looking for romance, commitment (sort of, mostly) and ostentatious displays of affection, one must turn to birds.

In a complete reversal from their mammalian brethren more than 90% of bird species are socially monogamous, said Peggy O’Connell, a retired professor who spent 31 years in Eastern Washington’s biology department.

Note: Socially monogamous means the males help care for the offspring. It doesn’t mean males don’t philander. They often do.

Why such a marked difference? Likely because birds are warm-blooded and lay eggs, requiring incubation. Males help incubate or provide food for the mothers. The work isn’t done when the chicks hatch. Unlike mammals, who lactate, birds have to feed their babies – another way the male can pitch in.

Mountain bluebirds, which will start nesting in North Idaho and parts of Eastern Washington in late March are one such example. Males look for suitable nesting locations, but the final say goes to the females. While the female incubates the eggs, the male guards the nest from predators but also from other randy male bluebirds.

Another local example? The northern pygmy owl, which is also seasonally monogamous. While the female incubates the eggs, the male feeds the female.

Within this general framework there is a dizzying amount of variety and plenty of exceptions, O’Connell said. Consider the common house sparrow. These diminutive invasive birds (first introduced in New York in 1851) are also monogamous throughout a breeding season.

Which doesn’t prevent infidelity.

O’Connell recalls watching a male and female house sparrow, a species that is monogamous for a season, return to their nest. The male went inside. The female stayed outside, preening a bit. Soon another male arrived. The two mated. He flew off and she returned to her mate inside their home. More advanced genetic testing has shown that this sort of hanky-panky is quite common among all species.

“That’s the basis for so many murder mysteries,” she said.

As for other monogamous area mammals, perhaps there is no better example than the beaver, which pairs for life (although genetic testing has revealed a scandalous amount of sleeping around). Like birds, there are structural and environmental factors which seem to reward monogamy. Beavers have lodges, the construction of which is time- and resource-consuming, work in which both mates partake. Plus, the kits don’t leave the lodge for two years, yet another incentive for strong pair bonding.

All of which creates a strong argument for the evolutionary and scientific reason for monogamy, O’Connell said. But too much reductive thinking can obscure other truths. Monogamous animals form emotional attachments to their mates, attachments that are mourned – in their own way – when lost. Research continues to show that numerous species mourn the death of mates.

At the same time, trying to argue that humans are somehow unaffected by evolution – and the sway it has on love and mating – is foolish, too.

“I think it’s shortsighted to think of human behavior as completely divorced from animal behavior,” O’Connell said. “We’re both shaped by evolution. We are animals. You lose a lot of your understanding of many aspects of human behavior … if you can’t see it in the broader perspective of evolution.”