Animal Attraction

People are more like animals than we like to admit sometimes. Rather, we tend to believe that animals can be so human sometimes. One area where the lines between humans and animals can become blurred is that of courtship rituals and relationships. This Valentine’s Day let’s look at “love” in the animal world. Hopefully our finned, feathered, and furred friends don’t feel as awkward as we do.

Many times, in the animal world it is the female who chooses a mate. Males might compete with each other not by fighting, but other means. Bowerbirds build little houses with decorated yards to impress females. Prairie chickens and sage grouse gather in a lek, where the males display for the females. South American birds called manakins show like an 80s break dance fight from a movie. It reminds me of teenage boys trying to upstage each other to get a girl’s attention.

In other species, brute strength carries the day for males eager to win mating rights. Large mammals like elk and bison have a dominant male who controls a harem of females, unless a younger and stronger challenger is able to put him out to pasture. This behavior reminds me of countless schoolyard and lunchroom fights over a girl.

Once these critters become an item, how long does their relationship last? It depends on the critter, just like with us. Some species are monogamous pairs, some are promiscuous males, and some are promiscuous females. For those that have a hard time getting around, like corals and clams, it’s free love. Look around at our own society and you’ll see the same scenarios, though not always for the same reasons.

In promiscuous relationships it is the female who raises the young with no paternal help in most cases. The bison and elk, where a male controls a harem, are male promiscuous. He will mate with as many of the females as he can. His goal is to have as many offspring as possible, while the female’s goal is ensure that her offspring have the best chance of survival. Surely the strongest and most fit of the males has the genes that offer better odds.

Sometimes it is the female who gets around. Several species of primates and birds practice this. The female hopes for better reproductive success by keeping her options open. It may also have the advantage that comes with several males all believing the offspring are theirs. Since the male’s goal is to have as many offspring as possible, the uncertainty will make sure they are looking out for any that are potentially theirs.

Everyone’s favorite relationship is monogamy. A pair mates for life and we think it’s so sweet. It’s almost like they’re married. This behavior is seen in bald eagles and gray wolves, for example. In this situation, both parents care for the young. In most cases, the pair nest together year-round. Not so for the Laysan albatross like Wisdom, who we met a few weeks ago. While she has a monogamous partner, they spend most of the year apart, coming together only for the breeding season. Once they chicks fledge the nest, they all go their separate ways. Wisdom and her mate will see each other again next year.

The messiest mating strategy is dispersal. Wind pollenating plants (think of pine trees) use this method, as do many sea creatures. Some environmental cue triggers corals, clams, and other sessile critters to release sperm and egg cells simultaneously. The sea becomes a soupy mess as the currents mix everything together. The pinnacle of group sex, critters who have never met or even seen each other become proud parents of children drifting off to parts unknown.

Every species is adapted to whatever mating and parenting style works best to ensure the next generation will survive. A general rule of thumb: fewer offspring get more intense parenting, while more offspring get little to no parental care. Either way, parents are playing the percentages to make sure they win the mating game.

 This week's information comes from Nature Education and the Washington Post.