Don’t We All Know This?
Male birds with those gorgeous feathers, songs and dances, have puzzled scientists, including Charles Darwin, for over a century.
After years of deliberation, Darwin decided that flashy plumage and elaborate song and dance could best be explained by female choice. Males developed showy plumage and elaborate songs in part, he said, to please choosy females.
“‘It is certain that amongst almost all animals there is a struggle between males for the possession of the female,’ Darwin wrote in 1874, in his book The Descent of Man and Selection in Relation to Sex. ‘Hence the females have the opportunity of selecting one out of several males, on the supposition their mental capacity suffices for the exertion of choice.'”
“Mental capacity?” We have definitely come a long way, baby. Our “mental capacity” works just fine.
I have been quoting from “The Forgotten Female, Now a Focus of Study” in Living Bird of Summer 2019. Let me continue.
At the time “Darwin’s theory on sexual selection and female choice set off a cultural explosion. It was fiercely attacked by Victorian society because it put females in control.
“Darwin’s contemporaries deemed the notion that women had choices as preposterous.
“‘Seldom or never does the female exert any choice. She is not the awarder of the prize, but rather a hunted creature,’ said German philosopher and psychologist Karl Groos in 1898.
“English botanist St. George Jackson Mivart, an early supporter of Darwin’s theory of natural selection, viciously attacked Darwin on sexual selection. Mivart went so far as to suggest that women were too amused by passing fancies to have any such exertion on evolution. Even fellow British naturalist (and codiscoverer of natural selection) Alfred Russel Wallace objected to Darwin’s idea of sexual selection.
“‘Female birds may be charmed or excited by the fine display of plumage by the males; but there is no proof whatever that slight differences in that display have any effect in determining their choice of a partner,’ Wallace wrote in 1898.
“To Wallace, male ornaments arose from the ‘surplus of strength, vitality, and growth-power,’ not simply beauty. These showy plumes meant the male had better genes — natural selection in disguise, the real reason why females choose heavily adorned males.
“While Victorian-era societal forces shelved Darwin’s notion of female choice 150 years ago, beauty as an evolutionary concept is enjoying a renaissance today. With a fresh perspective, biologists are reconsidering, and recognizing, the vital role of females in evolution and animal behavior.”
“Females,” says Cornell Lab Ornithology postdoctoral researcher Karan Odom, “play a much larger role than we previously thought.” And what is the knowledgeable Ms. Odom but a female scientist?
But let’s also credit the men, specifically in this case, Robert Trivers, a PhD student in biology at Harvard.
He suggested that because “females need to provide care for their young to ensure survival, females need to be choosy; they have more to lose than males.”
These modern-day studies left out Darwin’s beauty in favor of utility (thanks to Wallace), which many scientist found more palatable.
Quoting further in the same article, “until the late 1980s, many ornithologists assumed that songbirds were monogamous. Then along came the technology of paternity testing. DNA analysis revealed that sibling chicks in the same nest frequently came from different fathers.”
When Canadian ornithologist Bridget Stutchbury of York University in Toronto placed radio transmitters on the backs of female Hooded Warblers, she discovered that they were calling loudly to male Hooded Warblers, as if to say: “Hey, I’m over here!”
Stutchbury’s teams also discovered that female Blue-headed Vireos leave their nesting territory after the eggs hatch to check out the bachelor scene. As soon as her young fledge, she’s off to mate with another male, leaving her first mate to raise the young alone.
I’ll close with research from Kent McFarland, cofounder of the Vermont Center for Ecostudies, who suggests females will mate with multiple males if food is scarce.
If there’s plenty, they’ll stick with one — building connections and enlisting more helpers into foraging for food to feed the hungry chicks in the nest.
Makes sense to us all but hush. Let’s not tell the men.
Susan Crossett has lived in Arkwright for more than 20 years. A lifetime of writing led to these columns as well as two novels. Her Reason for Being was published in 2008 with Love in Three Acts following in 2014. Information on all the Musings, her books and the author may be found at Susancrossett.com.