written by: Kim O'Neal•edited by: Laurie Patsalides•updated: 7/8/2011
Many ornithologists believe that over 90% of bird species demonstrate some degree of monogamy in their relationships with their mating partners. A closer look at the mating behavior of birds and why it's essential to the family structure and care of the offspring.
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Many people have wondered at the possibility of monogamy in real life; pointing to birds as poster-children of faithfulness and devotion in a species.The truth about monogamy in birds may be somewhat disappointing to those who define monogamy as a state of remaining mentally, spiritually, and sexually devoted to only one partner for the entirety of their lives “until death do us part."
Many researchers have concluded that more than 90% of bird species demonstrate a heavy helping of monogamy in their mating behavior, especially around mating season.However a bird’s definition of monogamy varies somewhat from our romanticized, unrealistic ideal of it.
Most human beings become aware of the “problem" with monogamy once they reach sexual maturity.The idea we grow up with—that we fall in love, court our partner, get married, make babies, and live happily ever after is a pretty story, but the reality is a messy picture.Real, honest love doesn’t live by any rules.In so many ways, human monogamy is very similar to bird monogamy… although birds seem to have a much easier time with it.
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Mating Pair l Snowy Egret Mating Display
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Birds and Monogamy
What does monogamy actually look like in the bird kingdom?In some rare instances, like the wild goose and the bald eagle, a single mated pair will remain faithful to one another throughout their lives—unless one of them should die prematurely.Most songbirds remain faithful for a single mating season, sticking together long enough to build their nest and hatch their young.Come next mating season, the mating pair may find each other again… or they may fly their separate ways and find new mating partners.
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Can Birds Be in Love?
For the majority of bird species, the capacity to love is incredibly obvious to birdwatchers.Birds demonstrate their admiration and devotion to their chosen partners with touching sincerity.Many mated pairs continue to “court" one another long after mating season has come and gone; flying beside one another, snuggling, kissing (billing,) and sharing food with one another, with no reproductive expectations.
Should one mate die, the surviving mate seems to go through a behavior of mourning, acting confused and deeply upset, before seeking another mate for the following mating season.While sexual monogamy isn’t always the case, even within some mated pairs, social monogamy--showing favor to one partner above all others--is incredibly common bird behavior.Birds earned their standing as the universal symbol of love not for their sexual behavior, but for their deeply loving and affectionate nature.
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Snuggling l Kissing (Billing)
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Evolution of Monogamy
Genuine love and affection between a mating pair of animals is a behavior that occurs very rarely in nature.For a long time, humans believed they were the only creatures on Earth capable of experiencing love.Biologically speaking, monogamous behavior can only hold back the evolution of a species, limiting the abundance and diversity of the offspring.What do birds stand to gain by falling in love with one another?
Many ornithologists believe that monogamy in birds evolved in response to the needs of their offspring.Being a bird parent is such a demanding job, it literally takes two to do it.One bird would have such a difficult time keeping her eggs warm, keeping herself fed, and keeping an eye out for predators all at the same time… she’d never get any sleep.
Birds take shifts incubating eggs, gathering food, and keeping watch to make the job go smoother. Within most species of large, predator birds, the female stays with the nest during the whole of incubation while the male gathers food for the both of them.In many species of songbirds, the male takes his turn at the nest approximately every twelve hours, giving the female a chance to stretch her wings.
Hungry baby birds are very vocal about their needs, and can’t be left alone for very long.It takes two parents to gather food and supplies and keep new babies warm and safe from predators without neglecting their own needs in the process.
Regardless of the reasoning behind it, bird behavior is very different from many other animal species in how they interact with each other and with their young.Birds live to love and many form strong, life-long unions with their partners even after mating season has come and gone.